Category: alternative conception

Of opportunistic viruses and meat-eating bees

The birds viruses and the bees do it: Let's do it, let's…evolve

Keith S. Taber

bees that once were vegetarian actually decided to change their ways…

this group of bees realised that there's always animals that are dying and maybe there's enough competition on the flowers [so] they decided to switch

How the vulture bee got its taste for meat

I was struck by two different examples of anthropomorphism that I noticed in the same episode of the BBC's Science in Action radio programme/podcast.

Science in Action episode broadcast 5th December 2021

Anthropomorphism in science?

Anthropomorphism is the name given treating non-human entities as if they were human actors. An example of anthropomorphic language would be "the atom wants to donate an electron so that it can get a full outer shell" (see for example: 'A sodium atom wants to donate its electron to another atom'). In an example such as that, an event that would be explained in terms of concepts such as force and energy in a scientific account (the ionisation of an atom) is instead described as if the atom is a conscious agent that is aware of its status, has preferences, and acts to bring about desired ends.

Read about Anthropomorphism

Of course, an atom is not a complex enough entity to have mental experience that allows it to act deliberately in the world, so why might someone use such language?

  • Perhaps, if the speaker was a young learner, because they have not been taught the science.
  • Perhaps a non-scientist might use such language because they can only make sense of the abstract event in more familiar terms.

But what if the speaker was a scientist – a science teacher or a research scientist?

When fellow professionals (e.g., scientists) talk to each other they may often use a kind of shorthand that is not meant to be taken literally (e.g., 'the molecule wants to be in this configuration') simply because it can shorten and simplify more technical explanations that both parties understand. But when a teacher is talking to learners or a scientist is trying to explain their ideas to the general public, something else may be going on.

Read about Anthropomorphism in public science discourse

Anthropomorphism in science communication and education

In science teaching or science communication (scientists communicating science to the public) there is often a need to present abstract or complex ideas in ways that are accessible to the audience. At one level, teaching is about shifting what is to be taught from being unfamiliar to learners to being familiar, and one way to 'make the unfamiliar familiar' is to show it is in some sense like something already familiar.

Therefore there is much use of simile and analogy, and of telling stories that locate the focal material to be learned within a familiar narrative. Anthropomorphism is often used in this way. Inanimate objects may be said to want or need or try (etc.) as the human audience can relate to what it is to want or need or try.

Such techniques can be very useful to introduce novel ideas or phenomena in ways that are accessible and/or memorable ('weak anthropomorphism'). However, sometimes the person receiving these accounts may not appreciate their figurative nature as pedagogic / communicative aids, and may mistake what is meant to be no more than a starting point, a way into a new topic or idea, as being the scientific account itself. That is, these familiarisation techniques can work so well that the listener (or reader) may feel satisfied with them as explanatory accounts ('strong anthropomorphism').

Evolution – it's just natural (selection)

A particular issue arises with evolution, when often science only has hypothetical or incomplete accounts of how and why specific features or traits have been selected for in evolution. It is common for evolution to be misunderstood teleologically – that is, as if evolution was purposeful and nature has specific end-points in mind.

Read about teleology

The scientific account of evolution is natural selection, where none of genes, individual specimens, populations or species are considered to be deliberately driving evolution in particular directions (present company excepted perhaps – as humans are aware of evolutionary processes, and may be making some decisions with a view to the long-term future). 1

Yet describing evolutionary change in accord with the scientific account tends to need complex and convoluted language (Taber, 2017). Teleological and anthropomorphic shorthand is easier to comprehend – even if it puts a burden on the communicatee to translate the narrative into a more technical account.

What the virus tries to do

The first example from the recent Science in Action episode related to the COVID pandemic, and the omicron variant of the SARS-CoV-2 virus. This was the lead story on the broadcast/podcast, in particular how the travel ban imposed on Southern Africa (a case of putting the lid on the Petri dish after the variant had bolted?) was disrupting supplies of materials needed to address the pandemic in the countries concerned.

This was followed by a related item:

"Omicron contains many more mutations than previous variants. However scientists have produced models in the past which can help us understand what these mutations do. Rockefeller University virologist Theodora Hatziioannou produced one very similar to Omicron and she tells us why the similarities are cause for concern."

https://www.bbc.co.uk/programmes/w3ct1l4p

During this item, Dr Theodora Hatziioannou noted:

"When you give the virus the opportunity to infect so many people, then of course it is going to try not only every possible mutation, but every possible combination of mutations, until it finds one that really helps it overcome our defences."

Dr Theodora Hatziioannou interviewed on Science in Action

Dr Theodora Hatziioannou
Research Associate Professor
Laboratory of Retrovirology
The Rockefeller University

I am pretty sure that Dr Hatziioannou does not actually think that 'the virus' (which of course is composed of myriad discrete virus particles) is trying out different mutations intending to stop once it finds one which will overcome human defences. I would also be fairly confident that in making this claim she was not intending her listeners to understand that the virus had a deliberate strategy and was systematically working its way through a plan of action. A scientifically literature person should readily interpret the comments in a natural selection framework (e.g., 'random' variation, fitness, differential reproduction). In a sense, Dr Hatziioannou's comments may be seen as an anthropomorphic analogy – presenting the 'behaviour' of the virus (collectively) by analogy with human behavior.

Yet, as a science educator, such comments attract my attention as I am well aware that school age learners and some adult non-scientists may well understand evolution to work this way. Alternative conceptions of natural selection are very common. Even when students have been taught about natural selection they may misunderstand the process as Lamarckian (the inheritance of acquired characteristics – see for example 'The brain thinks: grow more fur'). So, I wonder how different members of the public hearing this interview will understand Dr Hatziioannou's analogy.

Even before COVID-19 came along, there was a tendency for scientists to describe viruses in such terms as as 'smart', 'clever' and 'sneaky' (e.g., 'So who's not a clever little virus then?'). The COVID pandemic seems to have unleashed a (metaphorical) pandemic of public comments about what the virus wants, and what it tries to achieve, and so forth. When a research scientist talks this way, I am fairly sure it is intended as figurative language. I am much less sure when, for example, I hear a politician telling the public that the virus likes cold weather ('What COVID really likes').

Vulture bees have the guts for it

The other item that struck me concerned vulture bees.

"Laura Figueroa from University of Massachusetts in Amhert [sic] in the US, has been investigating bees' digestive systems. Though these are not conventional honey bees, they are Costa Rican vulture bees. They feed on rotting meat, but still produce honey."

https://www.bbc.co.uk/programmes/w3ct1l4p
Bees do not actually make reasoned choices about their diets
(Original image by Oldiefan from Pixabay)

The background is that although bees are considered (so I learned) to have evolved from wasps, and to all have become vegetarians, there are a few groups of bees that have reverted to the more primitive habits of eating meat. To be fair to them, these bees are not cutting down the forests to set up pasture and manage livestock, but rather take advantage of the availability of dead animals in their environment as a source of protein.

These vulture bees (or carrion bees) are able to do this because their gut microbiomes consist of a mix of microbes that can support them in digesting meat, allowing them to be omnivores. This raises the usual kind of 'chicken and egg' question 1 thrown up by evolutionary developments: how did vegetarian bees manage to shift their diet: the more recently acquired microbes would not have been useful or well-resourced whilst the bees were still limiting themselves to a plant-based diet, but the vegetarian bees would not have been able to digest carrion before their microbiomes changed.

As part of the interview, Dr Figueroa explaied:

"These are more specialised bees that once they were vegetarian for a really long time and they actually decided to change their ways, there's all of this meat in the forest, why not take advantage? I find that super-fascinating as well, because how do these shifts happen?

Because the bees, really when we are thinking about them, they've got access to this incredible resource of all of the flowering plants that are all over the world, so then why switch? Why make this change?

Over evolutionary time there are these mutations, and, you know, maybe they'd have got an inkling for meat, it's hard to know how exactly that happened, but really because it is a constant resource in the forest, there's always, you know, this might sound a little morbid but there's always animals that are dying and there's always this turn over of nutrients that can happen, and so potentially this specialised group of bees realised that, and maybe there's enough competition on the flowers that they decided to switch. Or, they didn't decide, but it happened over evolutionary time.

Dr Laura Figueroa interviewed on Science in Action

Dr Figueroa does not know exactly how this happened – more research is needed. I am sure Dr Figueroa does not think the bees decided to change their ways in the way that a person might decide to change their ways – perhaps deciding to get more exercise and go to bed earlier for the sake of their health. I am also sure Dr Figueroa does not think the bees realised that there was so much competition feeding on the flowers that it might be in their interests to consider a change of diet, in the way that a person might decide to change strategy based on an evaluation of the competition. These are anthropomorphic figures of speech.

Dr Laura Figueroa, NSF Postdoctoral Research Fellow in Biology
Department of Entomology, Cornell University / University of Massachusetts in Amherst

As she said "they didn't decide, but it happened over evolutionary time". Yet it seems so natural to use that kind of language, that is to frame the account in a narrative that makes sense in terms of how people experience their lives.

Again, the scientifically literate should appreciate the figurative use of language for what it is, and it is difficult to offer an accessible account without presenting evolutionary change as purposive and the result of deliberation and strategy. Yet, I cannot help wondering if this kind of language may reinforce some listeners' alternative conceptions about how natural selection works.

Work cited:
Notes

1 The 'selfish' gene made famous by Dawkins (1976/1989) is not really selfish in the sense a person might be – rather this was an analogy which helped shift attention from changes at the individual or species level when trying to understand how evolution occurs, to changes in the level of distinct genes. If a mutation in a specific gene leads to a change in the carrying organism that (in turn) leads to that specimen having greater fitness then the gene itself has an increased chance of being replicated. So, from the perspective of focusing on the genes, the change at the species level can be seen as a side effect of the 'evolution' of the gene. The gene may be said to be (metaphorically) selfish because it does not change for the benefit of the organism, but to increase its own chances of being replicated. Of course, that is also an anthropomorphic narrative – actually the gene does not deliberately mutate, has no purpose, has no notion of replication, indeed, does not even 'know' it is a gene, and so forth.

2 Such either/or questions can be understood as posing false dichotomies (here, either the bees completely changed their diets before their microbiomes or their microbiomes changed dramatically before their diets shifted) when what often seems most likely is that change has been slow and gradual.

Climate change – either it is certain OR it is science

Is there a place for absolute certainty in science communication?

Keith S. Taber

I just got around to listening to the podcast of the 10th October episode of Science in Action. This was an episode entitled 'Youngest rock samples from the moon' which led with a story about rock samples collected on the moon and brought to earth by a Chinese mission (Chang'e-5). However, what caused me to, metaphorically at least, prick up my ears was a reference to "absolute certainty".

BBC Science in Action episode, 10th October, 2021

Now the tag line for Science in Action is "The BBC brings you all the week's science news". I think that phrase reveals something important about science journalism – it may be about science, but it is journalism, not science.

That is not meant as some kind of insult. But science in the media is not intended as science communication between scientists (they have journals and conferences and so forth), but science communicated to the public – which means it has to be represented in a form suitable for a general, non-specialist audience.

Read about science in public discourse and the media

Scientific and journalistic language games

For, surely, "all the week's science news" cannot be covered in one half-hour broadcast/podcast. 1

My point is that "The BBC brings you all the week's science news" is not intended to be understood and treated as a scientific claim, but as something rathere different. As Wittgenstein (1953/2009) famously pointed out, language has to be understood in specific contexts, and there are different 'language games'. So, in the genre of the scientific report there are particular standards and norms that apply to the claims made. Occasionally these norms are deliberately broken – perhaps a claim is made that is supported by fabricated evidence, or for which there is no supporting evidence – but this would be judged as malpractice, academic misconduct or at least incompetence. It is not within the rules of that game

However, the BBC's claim is part of a different 'language game' – no one is going to be accused of professional misconduct because, objectively, Science in Action does not brings a listener all the week's science news. The statement is not intended to be understood as an objective knowledge claim, but more a kind of motto or slogan; it is not to be considered 'false' because it not objectively correct. Rather, it is to be understood in a fuzzy, vague, impressionistic way.

To ask whether "The BBC brings you all the week's science news" through Science in Action is a true or false claim would be a kind of category error. The same kind of category error that occurs if we ask whether or not a scientist believes in the ideal gas law, the periodic table or models of climate change.

Who invented gravity?

This then raises the question of how we understand what professional academic scientists say on a science news programme that is part of the broadcast media in conversation with professional journalists. Are they, as scientists, engaged in 'science speak', or are they as guests on a news show engaged in 'media speak'?

What provoked this thought with was comments by Dr Fredi Otto who appeared on the programme "to discuss the 2021 Nobel Prizes for Science". In particular, I was struck by two specific comments. The second was:

"…you can't believe in climate change or not, that would just be, you believe in gravity, or not…"

Dr Friederike Otto speaking on Science in Action

Which I took to mean that gravity is so much part of our everyday experience that it is taken-for-granted, and it would be bizarre to have a debate on whether it exists. There are phenomena we all experience all the time that we explain in terms of gravity, and although there may be scope for debate about gravity's nature or its mode of action or even its universality, there is little sense in denying gravity. 2

Newton's notion of gravity predominated for a couple of centuries, but when Einstein proposed a completely different understanding, this did not in any sense undermine the common ('life-world' 2) experience labelled as gravity – what happens when we trip over, or drop something, or the tiring experience of climbing too many steps. And, of course, the common misconception that Newton somehow 'discovered' gravity is completely ahistorical as people had been dropping things and tripping over and noticing that fruit falls from trees for a very long time before Newton posited that the moon was in freefall around the earth in a way analogous to a falling apple!

Believing in gravity

Even if, in scientific terms, believing in a Newtonian conceptualisation of gravity as a force acting at a distance would be to believe something that was no longer considered the best scientific account (in a sense the 'force' of gravity becomes a kind of epiphenomenon in a relativistic account of gravity); in everyday day terms, believing in the phenomenon of gravity (as a way of describing a common pattern in experience of being in the world) is just plain common sense.

Dr Otto seemed to be suggesting that just as gravity is a phenomenon that we all take for granted (regardless of how it is operationalised or explained scientifically), so should climate change be. That might be something of a stretch as the phenomena we associate with gravity (e.g., dense objects falling when dropped, ending up on the floor when we fall) are more uniform than those associated with climate change – which is of course why one tends to come across more climate change deniers than gravity deniers. To the best of my knowledge, not even Donald Trump has claimed there is no gravity.

But the first comment that gave me pause for thought was:

"…we now can attribute, with absolute certainty, the increase in global mean temperature to the increase in greenhouse gases because our burning of fossil fuels…"

Dr Friederike Otto speaking on Science in Action
Dr Fredi Otto has a profile page at the The Environmental Change Unit,
University of Oxford

Absolute certainty?

That did not seem to me like a scientific statement – more like the kind of commitment associated with belief in a religious doctrine. Science produces conjectural, theoretical knowledge, but not absolute knowledge?

Surely, absolute certainty is limited to deductive logic, where proofs are possible (as in mathematics, where conclusions can be shown to inevitably follow from statements taken as axioms – as long as one accepts the axioms, then the conclusions must follow). Science deals with evidence, but not proof, and is always open to being revisited in the light of new evidence or new ways of thinking about things.

Read about the nature of scientific knowledge

Science is not about belief

For example, at one time many scientists would have said that the presence of an ether 3 was beyond question (as for example waves of light travelled from the sun to earth, and waves motion requires a medium). Its scientific characterisation -e.g., the precise nature of the ether, its motion relative to the earth – were open to investigation, but its existence seemed pretty secure.

It seemed inconceivable to many that the ether might not exist. We might say it was beyond reasonable doubt. 4 But now the ether has gone the way of caloric and phlogiston and N-rays and cold fusion and the four humours… It may have once been beyond reasonable doubt to some (given the state of the evidence and the available theoretical perspectives), but it can never have been 'absolutely certain'.

To suggest something is certain may open us to look foolish later: as when Wittgenstein himself suggested that we could be certain that "our whole system of physics forbids us to believe" that people could go to the moon.

Science is the best!

Science is the most reliable and trustworthy approach to understanding the natural world, but a large part of that strength comes from it never completely closing a case for good – from never suggesting to have provided absolute certainty. Science can be self-correcting because no scientific idea is 'beyond question'. That is not to say that we abandon, say, conversation of energy at the suggestion of the first eccentric thinker with designs for a perpetual motion machine – but in principle even the principle of conservation of energy should not be considered as absolutely certain. That would be religious faith, not scientific judgement.

So, we should not believe. It should not be considered absolutely certain that "the increase in global mean temperature [is due to] the increase in greenhouse gases because [of] our burning of fossil fuels", as that suggests we should believe it as a doctrine or dogma, rather than believe that the case is strong enough to make acting accordingly sensible. That is, if science is always provisional, technically open to review, then we can never wait for absolute certainty before we act, especially when something seems beyond reasonable doubt.

You should not believe scientific ideas

The point is that certainty and belief are not really the right concepts in science, and we should avoid them in teaching science:

"In brief, the argument to be made is that science education should aim for understanding of scientific ideas, but not for belief in those ideas. To be clear, the argument is not just that science education should not intend to bring about belief in scientific ideas, but rather that good science teaching discourages belief in the scientific ideas being taught."

Taber, 2017: 82

To be clear – to say that we do not want learners to believe in scientific ideas is NOT to say we want them to disbelieve them! Rather, belief/disbelief should be orthogonal to the focus on understanding ideas and their evidence base.

I suggested above that to ask whether "The BBC brings you all the week's science news" through Science in Action is a true or false claim would be a kind of category error. I would suggest it is a category error in the same sense as asking whether or not people should believe in the ideal gas law, the periodic table, or models of climate change.

"If science is not about belief, then having learners come out of science lessons believing in evolution, or for that matter believing that magnetic field lines are more concentrated near the poles of a magnet, or believing that energy is always conserved, or believing that acidic solutions contain solvated hydrogen ions,[5] misses the point. Science education should help students understand scientific ideas, and appreciate why these ideas are found useful, and something of their status (for example when they have a limited range of application). Once students can understand the scientific ideas then they become available as possible ways of thinking about the world, and perhaps as notions under current consideration as useful (but not final) accounts of how the world is."

Taber, 2017: 90

But how do scientists cross the borders from science to science communication?

Of course many scientists who have studied the topic are very convinced that climate change is occurring and that anthropogenic inputs into the atmosphere are a major or the major cause. In an everyday sense, they believe this (and as they have persuaded me, so do I). But in a strictly logical sense they cannot be absolutely certain. And they can never be absolutely certain. And therefore we need to act now, and not wait for certainty.

I do not know if Dr Otto would refer to 'absolute certainty' in a scientific context such as a research paper of a conference presentation. But a radio programme for a general audience – all ages, all levels of technical background, all degrees of sophistication in appreciating the nature of science – is not a professional scientific context, so perhaps a different language game applies. Perhaps scientists have to translate their message into a different kind of discourse to get their ideas across to the wider public?

The double bind

My reaction to Dr Otto's comments derived from a concern with public understanding of the nature of science. Too often learners think scientific models and theories are meant to be realistic absolute descriptions of nature. Too often they think science readily refutes false ideas and proves the true ones. Scientists talking in public about belief and absolute certainty can reinforce these misconceptions.

On the other hand, there is probably nothing more important that science can achieve today than persuade people to act to limit climate change before we might bring about shifts that are (for humanity if not for the planet) devastating. If most people think that science is about producing absolute certain knowledge, then any suggestion that there is uncertainty over whether human activity is causing climate change is likely to offer the deniers grist, and encourage a dangerous 'well let's wait till we know for sure' posture. Even when it is too late and the damage has been done, if there are any scientists left alive, they still will not know absolutely certainly what caused the changes.

"…Lord, here comes the flood
We'll say goodbye to flesh and blood
If again the seas are silent
In any still alive
It'll be those who gave their island to survive…"

(Peter Gabriel performing on the Kate Bush TV special, 1979: BBC Birmingham)

So, perhaps climate scientists are in a double bind – they can represent the nature of science authentically, and have their scientific claims misunderstood; or they can do what they can to get across the critical significance of their science, but in doing so reinforce misconceptions of the nature of scientific knowledge.

Coda

I started drafting this yesterday: Thursday. By coincidence, this morning, I heard an excellent example of how a heavyweight broadcast journalist tried to downplay a scientific claim because it was couched as not being absolutely certain!

Works cited:

Notes

1 An alternative almost tautological interpretation might be that the BBC decides what is 'science news', and it is what is included in Science in Action, might fit some critics complaints that the BBC can be a very arrogant and self-important organisation – if only because there are stories not covered in Science in Action that do get covered in the BBC's other programmes such as BBC Inside Science.

2 This might be seen as equivalent to saying that the life-world claim that gravity (as is commonly understood and experienced) exists is taken-for-granted Schutz & Luckmann, 1973). A scientific claim would be different as gravity would need to be operationally defined in terms that were considered objective, rather that just assuming that everyone in the same language community shares a meaning for 'gravity'.

3 The 'luminiferous' aether or ether. The ether was the name given to the fifth element in the classical system where sublunary matter was composed of four elements (earth, water, air, fire) and the perfect heavens from a fifth.

(Film  director Luc Besson's sci-fi/fantasy movie 'The Fifth Element' {1997, Gaumont Film Company} borrows from this idea very loosely: Milla Jovovich was cast in the title role as a perfect being who is brought to earth to be reunited with the other four elements in order to save the world.)

4 Arguably the difference between forming an opinion on which to base everyday action (everyday as in whether to wear a rain coat, or to have marmalade on breakfast toast, not as in whether to close down the global fossil fuel industry), and proposing formal research conclusions can be compared to the difference between civil legal proceedings (decided on the balance of probabilities – what seems most likely given the available evidence) and criminal proceedings – where a conviction is supposed to depend upon guilt being judged beyond reasonable doubt given the available evidence (Taber, 2013).

Read about writing-up research

5 Whether acids do contain hydrated hydrogen ions may seem something that can reasonably be determined, at least beyond reasonable doubt, by empirical investigation. But actually not, as what counts as an acid has changed over time as chemists have redefined the concept according to what seemed most useful. (Taber, 2019, Chapter 6: Conceptualising acids: Reimagining a class of substances).

Move over Mendeleev, here comes the new Mendel

Seeking the islets of Filipenka Henadzi

Keith S. Taber

"new chemical elements with atomic numbers 72-75 and 108-111 are supposedly revealed, and also it is shown that for heavy elements starting with hafnium, the nuclei of atoms contain a larger number of protons than is generally accepted"

Henadzi, 2019, p.2

Somehow I managed to miss a 2019 paper bringing into doubt the periodic table that is widely used in chemistry. It was suggested that many of the heavier elements actually have higher atomic numbers (proton numbers) than had long been assumed, with the consequence that when these elements are correctly re-positioned it reveals two runs of elements that should be in the periodic table, but which till now have not been identified by chemists.

According to Henadzi we need to update the periodic table and look for eight missing elements (original image by Image by Gerd Altmann from Pixabay)

Henadzi (2019) suggests that "I would like to name groups of elements with the numbers 72-75 and 108-111 [that is, those not yet identified that should have these numbers], the islets of Filipenka Henadzi."

The orginal Mendeleev

This is a bit like being taken back to when Dmitri Mendeleev first proposed his periodic table and had the courage to organise elements according to patterns in their properties, even though this left gaps that Mendeleev predicted would be occupied by elements yet to be discovered. The success of (at least some) of his predictions is surely the main reason why he is considered the 'father' of the periodic table, even though others were experimenting with similar schemes.

Now it has been suggested that we still have a lot of work to do to get the periodic table right, and that the version that chemists have used (with some minor variations) for many decades is simply wrong. This major claim (which would surely be considered worthy of the Nobel prize if found correct) was not published in Nature or Science or one of the prestigious chemistry journals published by learned societies such as the Royal Society of Chemistry, but in an obscure journal that I suspect many chemists have never heard of.

The original Mendel

This is reminiscent of the story of Mendel's famous experiments with inheritance in pea plants. Mendel's experiments are now seen as seminal in establishing core ideas of genetics. But Mendel's research was ignored for many years.

He presented his results at meetings of the Natural History Society of Brno in 1865 and then published them in a local German language journal – and his ideas were ignored. Only after other scientists rediscovered 'his' principles in 1900, long after his death, was his work also rediscovered.

Moreover, the discussion of this major challenge to accepted chemistry (and physics if I have understood the paper) is buried in an appendix of a paper which is mostly about the crystal structures of metals. It seems the appendix includes a translation of work previously published in Russian, explaining why, oddly, a section part way through the appendix begins "This article sets out the views on the classification of all known chemical elements, those fundamental components of which the Earth and the entire Universe consists".

Calling out 'predatory' journals

I have been reading some papers in a journal that I believed, on the basis of its misleading title and website details, was an example of a poor-quality 'predatory journal'. That is, a journal which encourages submissions simply to be able to charge a publication fee (currently $1519, according to the website), without doing the proper job of editorial scrutiny. I wanted to test this initial evaluation by looking at the quality of some of the work published.

One of the papers I decided to read, partly because the topic looked of particular interest, was 'Nature of Chemical Elements' (Henadzi, 2019). Most of the paper is concerned with the crystal structures of metals, and presenting a new model to explain why metals have the structure they do. This is related to the number of electrons per atom that can be considered to be in the conduction band – something that was illustrated with a simple diagram that unfortunately, to my reading at least, was not sufficiently elaborated.1

The two options referred to seem to refer to n-type (movement of electrons) and p-type (movement of electrons that can be conceptualised as movement of a {relatively} positive hole, as in semi-conductor materials) – Figure 1 from Henadzi, 2019: p2

However, what really got my attention was the proposal for revising the periodic table and seeking eight new elements that chemists have so far missed.

Beyond Chadwick

Henadzi tells readers that

"The innovation of this work is that in the table of elements constructed according to the Mendeleyev's law and Van-den- Broek's rule [in effect that atomic number in the periodic table = proton number], new chemical elements with atomic numbers 72-75 and 108-111 are supposedly revealed, and also it is shown that for heavy elements starting with hafnium, the nuclei of atoms contain a larger number of protons than is generally accepted. Perhaps the mathematical apparatus of quantum mechanics missed some solutions because the atomic nucleus in calculations is taken as a point."

Henadzi, 2019, p.4

Henadzi explains

"When considering the results of measuring the charges of nuclei or atomic numbers by James Chadwick, I noticed that the charge of the core of platinum is rather equal not to 78, but to 82, which corresponds to the developed table. For almost 30 years I have raised the question of the repetition of measurements of the charges of atomic nuclei, since uranium is probably more charged than accepted, and it is used at nuclear power plants."

Henadzi, 2019, p.4

Now Chadwick is most famous for discovering the neutron – back in 1932. So he was working a long time ago, when atomic theory was still quite underdeveloped and with apparatus that would seem pretty primitive compared with the kinds of set up used today to investigate the fundamental structure of matter. That is, it is hardly surprising if his work which was seminal nearly a century ago had limitations. Henadzi however seems to feel that Chadwick's experiments accurately reveal atomic numbers more effectively than had been realised.

Sadly, Henadzi does not cite any specific papers by Chadwick in his reference list, so it is not easy to look up the original research he is discussing. But if Henadzi is suggesting that data produced almost a century ago can be interpreted as giving some elements different atomic numbers to those accepted today, the obvious question is what other work, since, establishes the accepted values, and why should it not be trusted. Henadzi does not discuss this.

Explaining a long-standing mystery

Henadzi points out that whereas for the lighter elements the mass number is about twice the atomic number (that is, the number of neutrons in a nucleus approximately matches the number of protons) as one proceeds through the period table this changes such the ratio of protons:neutrons shifts to give an increasing excess of neutrons. Henadzi also implies that this is a long standing mystery, now perhaps solved.

"Each subsequent chemical element is different from the previous in that in its core the number of protons increases by one, and the number of neutrons increases, in general, several. In the literature this strange ratio of the number of neutrons to the number of protons for any the kernel is not explained. The article proposes a model nucleus, explaining this phenomenon."

Henadzi, 2019, p.5

Now what surprised me here was not the pattern itself (something taught in school science) but the claim that the reason was not known. My, perhaps simplistic, understanding is that protons repel each other because of their similar positive electrical charges, although the strong nuclear force binds nucleons (i.e., protons and neutrons collectively) into nuclei and can overcome this.

Certainly what is taught in schools is that as the number of protons increases more neutrons are needed to be mixed in to ensure overall stability. Now I am aware that this is very much an over-simplification, what we might term a curriculum model or teaching model perhaps, but what Henadzi is basically suggesting seems to be this very point, supplemented by the idea that as the protons repel each other they are usually found at the outside of the nucleus alongside an equal number of neutrons – with any additional neutrons within.

The reason for not only putting protons on the outer shell of a large nucleus in Henadzi's model seems to relate to the stability of alpha particles (that is, clumps of two protons and two neutrons, as in the relatively stable helium nucleus). Or, at least, that was my reading of what is being suggested,

"For the construction of the [novel] atomic nucleus model, we note that with alpha-radioactivity of the helium nucleus is approximately equal to the energy.

Therefore, on the outer layer of the core shell, we place all the protons with such the same number of neutrons. At the same time, on one energy Only bosons can be in the outer shell of the alpha- particle nucleus and are. Inside the Kernel We will arrange the remaining neutrons, whose task will be weakening of electrostatic fields of repulsion of protons."

Henadzi, 2019, p.5

The lack of proper sentence structure does not help clarify the model being mooted.

Masking true atomic number

Henadzi's hypothesis seems to be that when protons are on the surface of the nucleus, the true charge, and so atomic number, of an element can be measured. But sometimes with heavier elements some of the protons leave the surface for some reason and move inside the nucleus where their charge is somehow shielded and missed when nuclear charge is measured. This is linked to the approximation of assuming that the charge on an object measured from the outside can be treated as a point charge.

This is what Henadzi suggests:

"Our nuclear charge is located on the surface, since the number of protons and the number of neutrons in the nucleus are such that protons and neutrons should be in the outer layer of the nucleus, and only neutrons inside, that is, a shell forms on the surface of the nucleus. In addition, protons must be repelled, and also attracted by an electronic fur coat. The question is whether the kernel can be considered a point in the calculations and up to what times? And the question is whether and when the proton will be inside the nucleus….if a proton gets into the nucleus for some reason, then the corresponding electron will be on the very 'low' orbit. Quantum mechanics still does not notice such electrons. Or in other words, in elements 72-75 and 108-111, some protons begin to be placed inside the nucleus and the charge of the nucleus is screened, in calculations it cannot be taken as a point."

Henadzi, 2019, p.5

So, I think Henadzi is suggesting that if a proton gets inside the nucleus, its associated electron is pulled into a very close orbit such that what is measured as nuclear charge is the real charge on the nucleus (the number of protons) partially cancelled by low lying electrons orbiting so close to the nucleus that they are within what we might call 'the observed nucleus'.

This has some similarity to the usual idea of shielding that leads to the notion of core charge. For example, a potassium atom can be modelled simplistically for some purposes as a single electron around a core charge of plus one (+19-2-8-8) as, at least as a first approximation, we can treat all the charges within the outermost N (4th) electron shell (the 19 protons and 18 electrons) as if a single composite charge at the centre of the atom. 2

Dubious physics

Whilst I suspect that the poor quality of the English and the limited detail included in this appendix may well mean I am missing part of the argument here, I am not convinced. Besides the credibility issue (how can so many scientists have missed this for so long?) which should never be seen as totally excluding unorthodox ideas (the same thing could have been asked about most revolutionary scientific breakthroughs) my understanding is that there are already some quite sophisticated models of nuclear structure which have evolved alongside programmes of emprical research and which are therefore better supported than Henadzi's somewhat speculative model.

I must confess to not understanding the relevance of the point charge issue as this assumption/simplification would seem to work with Henadzi's model – from well outside the sphere defined by the nucleus plus low lying electrons the observed charge would be the net charge as if located at a central point, so the apparent nuclear charge would indeed be less than the true nuclear charge.

But my main objection would be the way electrostatic forces are discussed and, in particular, two features of the language:

Naked protons

protons must be repelled, and also attracted by an electronic fur coat…

I was not sure what was meant by "protons must be repelled, and also attracted by an electronic fur coat". The repulsion between protons in the nucleus is balanced by the strong nuclear force – so what is this electronic 'fur coat'?

This did remind me of common alternative conceptions that school students (who have not yet learned about nuclear forces) may have, along the lines that a nucleus is held together because the repulsion between protons is balanced by their attraction to the ('orbiting') electrons. Two obvious problems with this notion are that

  • the electrons would be attracting protons out of the nucleus just as they are repelling each other (that is, these effects reinforce, not cancel), and
  • the protons are much closer to each other than to the electrons, and the magnitude of force between charges diminishes with distance.

Newton's third law and Coulomb's law would need to be dis-applied for an electronic effect to balance the protons' mutual repulsions. (On Henadzi's model the conjectured low lying electrons are presumably orbiting much closer to the nucleus than the 1s electrons in the K shell – but, even so, the proton-electron distance will be be much greater than the separation of protons in the nucleus.)3

But I may have misunderstood what Henadzi's meant here by the attraction of the fur coat and its role in the model.

A new correspondence principle?

if a proton gets into the nucleus for some reason, then the corresponding electron will be on the very 'low' orbit

Much more difficult to explain away is the suggestion that "if a proton gets into the nucleus for some reason, then the corresponding electron will be on the very 'low' orbit". Why? This is not explained, so it seems assumed readers will simply understand and agree.

In particular, I do not know what is meant by 'the corresponding electron'. This seems to imply that each proton in the nucleus has a corresponding electron. But electrons are just electrons, and as far as a proton is concerned, one electron is just like any other. All of the electrons attract, and are attracted by, all of the protons.

Confusing a teaching scheme for a mechanism?

This may not always be obvious to school level students, especially when atomic structure is taught through some kind of 'Aufbau' scheme where we add one more proton and one more electron for each consecutive element's atomic structure. That is, the hydrogen atom comprises of a proton and its 'corresponding' electron, and in moving on to helium we add another proton, with its 'corresponding' electron and some neutrons. These correspond only in the sense that to keep the atom neutral we have to add one negative charge for each positive charge. They 'correspond' in a mental accounting scheme – but not in any physical sense.

That is a conceptual scheme meant to do pedagogic work in 'building up' knowledge – but atoms themselves are just systems of fundamental particles following natural laws and are not built up by the sequential addition of components selected from some atomic construction kit. We can be misled into mistaking a pedagogic model designed to help students understand atomic structure for a representation of an actual physical process. (The nuclei of heavy elements are created in the high-energy chaos inside a star – within the plasma where it is too hot for them to capture the electrons needed to form neutral atoms.)

A similar category error (confusing a teaching scheme for a mechanism) often occurs when teachers and textbook authors draw schemes of atoms combining to form molecules (e.g., a methane molecule formed from a carbon atom and four hydrogen atoms) – it is a conceptual system to work with the psychological needs for students to have knowledge built up in manageable learning quanta – but such schemes do not reflect viable chemical processes.4

It is this kind of thinking that leads to students assuming that during homolytic bond fission each atom gets its 'own' electron back. It is not so much that this is not necessarily so, as that the notion of one of the electrons in a bond belonging to one of the atoms is a fiction.

The conservation of force conception (an alternative conception)

When asked about ionisation of atoms it is common for students to suggest that when an electron is removed from an atom (or ion) the remaining electrons are attracted more strongly because the force for the removed electron gets redistributed. It is as if within an atom each proton is taking care of attracting one electron. In this way of thinking a nucleus of a certain charge gives rise to a certain amount of force which is shared among the electrons. Removing an electron means a greater share of the force for those remaining. This all seems intuitive enough to many learners despite being at odds with basic physical principles (Taber, 1998).

I am not deducing that Henadzi, apparently a retired research scientist, shares these basic misconceptions found among students. Perhaps that is the case, but I would not be so arrogant as to diagnose this just from the quoted text. But that is my best understanding of the argument in the paper. If that is not what is meant, then I think the text needs to be clearer.

The revolution will not be televised…

In conclusion, this paper, published in what is supposedly a research journal, is unsatisfactory because (a) it makes some very major claims that if correct are extremely significant for chemistry and perhaps also physics, but (b) the claims are tucked away in an appendix, are not fully explained and justified, and do not properly cite work referred to; and the text is sprinkled with typographic errors, and seems to reflect alternative conceptions of basic science.

I very much suspect that Henadzi's revolutionary ideas are just wrong and should rightly be ignored by the scientific community, despite being published in what claims to be a peer-reviewed (self-describing 'leading international') research journal.

However, perhaps Henadzi's ideas may have merit – the peer reviewers and editor of the journal presumably thought so – in which case they are likely to be ignored anyway because the claims are tucked away in an appendix, are not fully explained and justified, and do not properly cite work referred to; and the text is sprinkled with typographic errors, and seems to reflect alternative conceptions of basic science. In this case scientific progress will be delayed (as it was when Mendel's work was missed) because of the poor presentation of revolutionary ideas.

How does the editor of a peer-reviewed journal move to a decision to publish in 4 days?
Let down by poor journal standards

So, either way, I do not criticise Henadzi for having and sharing these ideas – healthy science encompasses all sorts of wild ideas (some of which turn out not to have been so wild as first assumed) which are critiqued, tested, and judged by the community. However, Henadzi has not been well supported by the peer review process at the journal. Even if peer reviewers did not spot some of the conceptual issues that occurred to me, they should surely have noticed the incompleteness of the argument or at the very least the failures of syntax. But perhaps in order to turn the reviews around so quickly they did not read the paper carefully. And perhaps that is how the editor, Professor Nour Shafik Emam El-Gendy of the Egyptian Petroleum Research Institute, was able to move to a decision to publish four days after submission.5

If there is something interesting behind this paper, it will likely be missed because of the poor presentation and the failure of peer review to support the author in sorting the problems that obscure the case for the proposal. And if the hypothesis is as flawed as it seems, then peer review should have prevented it being published until a more convincing case could be made. Either way, this is another example of a journal rushing to publish something without proper scrutiny and concern for scientific standards.

Works cited
Footnotes:

1 My understanding of the conduction band in a metal is that due to the extensive overlap of atomic orbitals, a great many molecular orbitals are formed, mostly being quite extensive in scope ('delocalised'), and occurring with a spread of energy levels that falls within an energy band. Although strictly the molecular orbitals are at a range of different levels, the gaps between these levels are so small that at normal temperatures the 'thermal energy' available is enough for electrons to readily move between the orbitals (whereas in discrete molecules, with a modest number of molecular orbitals available, transitions usually require absorption of higher energy {visible or more often} ultraviolet radiation). So, this spread of a vast number of closely spaced energy levels is in effect a continuous band.

Given that understanding I could not make sense of these schematic diagrams. They SEEM to show the number of conduction electrons in the 'conduction band' as being located on, and moving around, a single atom. But I may be completely misreading this – as they are meant to be (cross sections through?) a tube.

"we consider a strongly simplified one- dimensional case of the conduction band. Option one: a thin closed tube, completely filled with electrons except one. The diameter of the electron is approximately equal to the diameter of the tube. With such a filling of the zone, with the local movement of the electron, there is an opposite movement of the "place" of the non-filled tube, the electron, that is, the motion of a non-negative charge. Option two: in the tube of one electron – it is possible to move only one charge – a negatively charged electron"

Henadzi, 2019, p.2

2 The shell model is a simplistic model, and for many purposes we need to use more sophisticated accounts. For example, the electrons are not strictly in concentric shells, and electronic orbitals 'interpenetrate' – so an electron considered to be in the third shell of an atom will 'sometimes' be further from the nucleus than an electron considered to be in the fourth shell. That is, a potassium 4s electron cannot be assumed to be completely/always outside of a sphere in which all the other atomic electrons (and the nucleus) are contained, so the the core cannot be considered as a point charge of +1 at the nucleus, even if this works as an approximation for some purposes. The effective nuclear charge from the perspective of the 4s electron will strictly be more than +1 as the number of shielding electrons is somewhat less than 18.

3 Whilst the model of electrons moving around the nucleus in planetary orbits may have had some heuristic value in the development of atomic theory, and may still be a useful teaching model at times (Taber, 2013), it seems it is unlikely to have the sophistication to support any further substantive developments to chemical theory.

4 It is very common for learners to think of chemistry in terms of atoms – e.g., to think of atoms as starting points for reactions; to assume that ions must derive from atoms. This way of thinking has been called the atomic ontology.

5 I find it hard to believe that any suitably qualified and conscientious referees would not raise very serious issues about this manuscript precluding publication in the form it appears in the journal. If the journal really does use peer review, as is claimed, one has to wonder who they think suitable to act as expert reviewers, and how they persuade them to write their reports so quickly.

Based on this, and other papers appearing in the journal, I suspect one of the following:

a) peer review does not actually happen, or

b) peer review is assigned to volunteers who are not experts in the field, and so are not qualified to be 'peers' in the sense intended when we talk of academic peer review, or

c) suitable reviewers are appointed, but instructed to do a very quick but light review ignoring most conceptual, logical, technical and presentation issues as long as the submission is vaguely on topic, or

di) appropriate peer reviewers are sought, but the editor does not expect authors to address reviewer concerns before approving publication, or possibly

dii) decisions to publish sub-standard work are made by administrators without reference to the peer reviews and the editor's input

Not a great experiment…

What was wrong with The Loneliness Experiment?

Keith S. Taber

The loneliness experiment, a.k.a. The BBC Loneliness Experiment was a study publicised through the BBC (British public service broadcaster), and in particular through it's radio programme All in the Mind, ("which covers psychology, neuroscience & mental health" according to presenter, Claudia Hammond's website.)1 It was launched back in February 2018 – pre-COVD.2

"All in the Mind: The Loneliness Experiment launches the world's largest ever survey of its kind on loneliness." https://www.bbc.co.uk/programmes/b09r6fvn

Claudia Hammond describes herself as an "award-winning broadcaster, author and psychology lecturer". In particular "She is Visiting Professor of the Public Understanding of Psychology at the University of Sussex" where according to the University of Sussex  "the post has been specially created for Claudia, who studied applied psychology at the University in the 1990s", so she is very well qualified for her presenting role. (I think she is very good at this role: she has a good voice for the radio and manages to balance the dual role of being expert enough to exude authority, whilst knowing how to ask necessarily naive questions of guests on behalf of non-specialist listeners.)

A serious research project

The study was a funded project based on a collaboration between academics from a number of universities, led by Prof Pamela Qualter, Professor of Education at the Manchester Institute of Education at the University of Manchester. Moreoever, "55,000 people from around the world chose to take part in the BBC Loneliness Experiment, making it the world's largest ever study on loneliness" (https://claudiahammond.com/bbc-loneliness-experiment/)

Loneliness is a serious matter that affects many people, and is not be made light of. So this was a serious study, on an important topic – yet every time I heard this mentioned on the radio (and it was publicised a good deal at the time) I felt myself mentally (and sometimes physically) cringe. Even without hearing precise details of the research design, I could tell this was simply not a good experiment.

This was not due to any great insight on my behalf, but was obvious from the way the work was being described. Readers may wish to see if they can spot for themselves what so irked me.

What is the problem with this research design?

This is how the BBC described the study at its launch:

The Loneliness Experiment, devised by Professor Pamela Qualter and colleagues, aims to look at causes and possible solutions to loneliness. And we want as many people as possible to fill in our survey, even if they've never felt lonely, because we want to know what stops people feeling lonely, so that more of us can feel connected.

https://www.bbc.co.uk/programmes/b09r6fvn

This is how Prof. Hammond described the research in retrospect:

55,000 people from around the world chose to take part in the BBC Loneliness Experiment, making it the world's largest ever study on loneliness. Researchers from the universities of Manchester, Brunel and Exeter, led by Professor Pamela Qualter and funded by the Wellcome Trust, developed a questionnaire asking people what they thought loneliness was, when they felt lonely and for how long.

https://claudiahammond.com/bbc-loneliness-experiment/

And this is how the work is described on the University of Manchester's pages:

The Loneliness Experiment was a study conducted by BBC Radio 4's All in the Mind….

The study asked respondents to give their opinions and record their experiences of loneliness and related topics, including friendship, relationships, and the use of technology – as well as recording lifestyle and background information. Respondents also engaged in a number of experiments.

The survey was developed by Professor Pamela Qualter, from The University of Manchester's Manchester Institute of Education (MIE), with colleagues from Brunel University London, and the University of Exeter. The work was funded by a grant from The Wellcome Trust.

https://www.seed.manchester.ac.uk/education/research/impact/bbc-loneliness-experiment/

When is an experiment not an experiment?

These descriptions make it obvious that the The Loneliness Experiment was not an experiment. Experiment is a specific kind of research – a methodology where the researchers randomly assign participants randomly to conditions, intervene in the experimental condition,and take measurements to see what effect the intervention has by comparing with measurements in a control condition. True experiments are extremely difficult to do in the social sciences (Taber, 2019), and often quasi-experiments or natural experiments are used which do not meet all the expectations for true experiments. BUT, to be an experiment there has to be something that can be measured as changing over time in relation to specified different conditions.

Experiment involves intervention (Image by Gerd Altmann from Pixabay)

Experiment is not the only methodology used in research – there are also case studies, there is action research and grounded theory, for example – and non-experimental research may be entirely appropriate in certain situations, and can be of very high quality. One alternative methodology is the survey which collects data form a sample of a population at some particular time. Although surveys can be carried out in various ways (for example, through a series of observations), especially common in social science is the survey (a methodology) carried out by using participant self-responses to a questionnaire (a research instrument).

it is clear from the descriptions given by the BBC, Professor Hammond and the University of Manchester that the The Loneliness Experiment was not actually an experiment at all, but basically a survey (even if, tantalisingly, the Manchester website suggests that "Respondents also [sic] engaged in a number of experiments". )

The answer to the question 'when is an experiment not an experiment?' might simply be: when it is something other than an experiment

Completing a questionnaire (Image by Andreas Breitling from Pixabay)

What's in a name: does it really matter?

Okay, so I am being pedantic again.

But I do think this matters.

I think it is safe to assume that Prof. Hammond, Prof. Qualter and colleagues know the difference between an experiment and a survey. Presumably someone decided that labelling the research as the loneliness study or the loneliness survey would not be accessible (or perhaps not as impressive) to a general audience and so decided to incorrectly use the label experiment as if experiment was synonymous with study/research.

As a former research methods lecturer, that clearly irks as part of my job was to teach new researchers about key research concepts. But I would hope that people actually doing research or learning to do research are not going to be confused by this mislabelling.

But, as a former school science teacher, I know that there is widespread public misunderstanding of key nature of science terms such as theory and experiment. School age students do need to learn what is meant by the word experiment, and what counts as an experiment, and the BBC is being unhelpful in presenting research that is not experimental as an experiment – as this will simply reinforce common misconceptions of what the term experiment is actually used to denote in research .

So, in summary, I'll score The BBC Loneliness Experiment

  • motivation – excellent;
  • reach – impressive;
  • presentation – unfortunate and misleading
Further reading:

Read about methodology

Read about experiments

Read about surveys

Work cited:

Taber, K. S. (2019). Experimental research into teaching innovations: responding to methodological and ethical challenges. Studies in Science Education, 55(1), 69-119. doi:10.1080/03057267.2019.1658058 [Download manuscript version]

Note:

1: Websites cited accessed on 28th August, 2021.

2: It would have been interesting to repeat when so many people around the world were in 'lock-down'. (A comparison between pre-COVID and pandemic conditions might have offered something of a natural experiment.)

Shock! A typical honey bee colony comprises only six chemicals!

Is it half a dozen of one, or six of the other?

Keith S. Taber

Bee-ware chemicals!
(Images by PollyDot and Clker-Free-Vector-Images from Pixabay)

A recent episode of the BBC Inside science radio programme and podcast was entitled 'Bees and multiple pesticide exposure'. This discussed a very important issue that I have no wish to make light of. Researchers were looking at the stressors which might be harming honey bees, very important pollinators for many plants, and concluded that these likely act synergistically. That is a colony suffering from, say a drought and at the same time a mite infection, will show more damage that one would expect from simply adding the typical harm of each as if independent effects.  Rather there are interactions.

This is hardly surprising, but is none-the-less a worrying finding.

Bees and multiple pesticide exposure episode of BBC Inside Science

However,  my 'science teacher' radar honed in on an aspect of the language used to explain the research. The researcher interviewed was Dr Harry Siviter of the University of Texas at Austin. As part of his presentation he suggested that…

"Exposure to multiple pesticides is the norm, not the exception. So, for example a study in North America showed that the average number of chemicals found in a honey bee colony is six, with a high of 42. So, we know that bees are exposed to multiple chemicals…"

Dr Harry Siviter

The phrase that stood out for me was "the average number of chemicals found in a honey bee colony is six" as clearly that did not make any sense scientifically. At least, not if the term 'chemical' was meant to refer to 'chemical substance'. I cannot claim to know just how many different substances would be found if one analysed honey bee colonies, but I am pretty confident the average would be orders of magnitude greater than six. An organism such as a bee (leaving aside for a moment the hive in which it lives) will be, chemically, 'made up' of a great many different proteins, amino acids, lipids, sugars, nuclei acids, and so forth.

"the average number of chemicals found in a honey bee colony is six"

From the context, I understood that Dr Siviter was not really talking about chemicals in general, but pesticides. So, I am (not for the first time) being a pedant in pointing out that technically he was wrong to suggest "the average number of chemicals found in a honey bee colony is six" as any suitably informed listener would have immediately, and unproblematically, understood what he meant by 'chemicals' in this context.

Yet, as a teacher, my instinct is to consider that programmes such as this, designed to inform the public about science, are not only heard by those who are already well-versed in the sciences. By its nature, BBC Inside Science is intended to engage with a broad audience, and has a role in educating the public about science. I also knew that this particular pedantic point linked to a genuine issue in science teaching.

A common alternative conception

The term chemical is not usually used in science discourse as such, but rather the term substance. Chemical substances are ubiquitous, although in most everyday contexts we do not come across many pure samples of single substances. Tap water is nearly all water, and table salt is usually about 99% sodium chloride, and sometimes metals such as copper or aluminium are used in more or less pure form. But these tend to be exceptions – most material entities we engage with are not pure substances ('chemicals'), rather being mixtures or even more complex (e.g., wood or carrot or hair).

In everyday life, the term chemical tends to be used more loosely – so, for example, household bleach may be considered 'a chemical'. More problematically 'chemicals' tends to be seen as hazardous, and often even poisonous. So, people object to there being 'chemicals' in their food – when of course their food comprises chemicals and we eat food to access those chemicals because we are also made up of a great many chemicals. Food with the chemicals removed is not food, or indeed, anything at all!

In everyday discourse 'chemical' is often associated with 'dangerous' (Image by Arek Socha from Pixabay)

So, science teachers not only have the problem that in everyday discourse the term 'chemical' does not map unproblematically on 'substance' (as it is often used also for mixtures), but even more seriously that chemicals are assumed to be bad, harmful, undesirable – something to be avoided and excluded. By contrast, the scientific perspective is that whilst some chemicals are potentially very harmful, others are essential for life. Therefore, it is unhelpful when science communicators (whether journalists, or scientists themselves) use the term 'chemical' to refer only to potentially undesirable chemicals (which even then tend to be undesirable only in certain contexts), such as pesticides which are found in, and may harm, pollinators.

I decided to dig into the background of the item.

The news item

I found a news item in 'the Conversation' that discuses the work.

Dr Siviter's Article in the Conversation

It began

"A doctor will always ask if you are on any other medication before they write you a prescription. This is because pharmaceuticals can interact with each other and potentially disrupt the treatment, or even harm the patient. But when agrochemicals, such as pesticides, are licensed for use on farms, little attention is paid to how they interact with one another, and so their environmental impact is underestimated."

Siviter, 2021

This seemed a very good point, made with an analogy that seemed very telling.

(Read about science analogies)

This was important because:

"We analysed data gathered in scientific studies from the last two decades and found that when bees are exposed to a combination of pesticides, parasites and poor nutrition, the negative impact of each is exacerbated. We say that the cumulative effect of all these things is synergistic, meaning that the number of bees that are killed is more than we would predict if the negative effects were merely added together."

Siviter, 2021

This seems important work, and raises an issue we should be concerned about. The language used here was subtly different from in the radio programme:

"Many agrochemicals, such as neonicotinoids, are systemic, meaning they accumulate in the environment over several months, and in some cases years. It is perhaps not surprising then that honeybee colonies across the US have on average six different agrochemicals present in their wax, with one hive contaminated with 39 [sic, not 42]. It's not just honeybees which are at risk, though: wild bees such as bumblebees are also routinely exposed."

Siviter, 2021

So, here it was not 'chemicals' that were being counted but 'agrochemicals' (and the average figure of 6 now referred not to the colony as a whole, but only to the beeswax.)

The meta-analysis

'Agrochemicals' was also the term used in the research paper in the prestigious journal Nature where the research had been first reported,

"we conducted a meta-analysis of 356 interaction effect sizes from 90 studies in which bees were exposed to combinations of agrochemicals, nutritional stressors and/or parasites."

Siviter, et al., 2021

A meta-analysis is a type of secondary research study which collects results form a range of related published studies and seeks to identify overall patterns.

The original research

Moreover, the primary study being referred to as the source of the dubious statistic (i.e., that "the average number of chemicals found in a honey bee colony is six") referred not to 'chemicals' but to "pesticides and metabolites" (that is, substances which would be produced as the bee's metabolism broke the pesticides down):

"We have found 121 different pesticides and metabolites within 887 wax, pollen, bee and associated hive samples….

Almost all comb and foundation wax samples (98%) were contaminated with up to 204 and 94 ppm [parts per million], respectively, of fluvalinate and coumaphos, and lower amounts of amitraz degradates and chlorothalonil, with an average of 6 pesticide detections per sample and a high of 39."

Mullin, et al., 2010

Translation and representation

Scientific research is reported in research journals primarily for the benefit of other researchers in the field, and so is formatted and framed accordingly – and this is reflected in the language used in primary sources.

A model of the flow of scientific to public knowledge (after McInerney et al., 2004)

Fig. 10.2 from Taber, 2013

It is important that science which impacts on us all, and is often funded from public funds, is accessible to the public. Science journalism, is an important conduit for the communication of science, and for his to be effective it has to be composed with non-experts in the public in mind.

(Read about science in public discourse and the media)

It is perfectly sensible and desirable for a scientist engaging with a public audience to moderate technical language to make the account of research more accessible for a non-specialist audience. This kind of simplification is also a core process in developing science curriculum and teaching.

(Read about representing science in the curriculum)

However, in the case of 'chemical' I would suggest scientists take care with using the term (and avoid it if possible), as science teachers commonly have to persuade students that chemicals are all around of us, are not always bad for us, are part of us, and are essential. That pesticides and their breakdown products have been so widely detected in bee colonies is a matter of concern, as pesticides are substances that are used because of their detrimental effects on many insects and other organisms that might damage crops.

Whilst that is science deserving public attention, there are a good many more than 6 chemicals in any bee colony, and – indeed – we would want most of them to be there.

References:

Balding black holes – a shaggy dog story

Resurrecting an analogy from a dead metaphor?

Keith S. Taber

Now there's a look in your eyes, like black holes in the sky…(Image by Garik Barseghyan from Pixabay)

I was intrigued by an analogy in a tweet

Like a shaggy dog in springtime, some black holes have to shed their "hair."

The link led me to an item at a webpage at 'Science News' entitled 'Black holes born with magnetic fields quickly shed them' written by Emily Conover. This, in turn, referred to an article in Physical Review Letters.

Now Physical Review Letters is a high status, peer-reviewed, journal.

(Read about peer review)

As part of the primary scientific literature, it publishes articles written by specialist scientists in a technical language intended to be understood by other specialists. Dense scientific terminology is not used to deliberately exclude general readers (as sometimes suggested), but is necessary for scientists to make a convincing case for new knowledge claims that seem persuasive to other specialists. This requires being precise, using unambiguous technical language."The thingamajig kind of, er, attaches to the erm, floppy bit, sort of" would not do the job.

(Read about research writing)

Science News however is news media – it publishes journalism (indeed, 'since 1921' the site reports – although that's the publication and not its website of course.) While science journalism is not essential to the internal processes of science (which rely on researchers engaging with each other's work though  scholarly critique and dialogue) it is very important for the public's engagement with science, and for the accountability of researchers to the wider community.

Science journalists have a job similar to science teachers – to communicate abstract ideas in a way that makes sense to their audience. So, they need to interpret research and explain it in ways that non-specialists can understand.

The news article told me

"Like a shaggy dog in springtime, some black holes have to shed…
Unlike dogs with their varied fur coats, isolated black holes are mostly identical. They are characterized by only their mass, spin and electric charge. According to a rule known as the no-hair theorem, any other distinguishing characteristics, or "hair," are quickly cast off. That includes magnetic fields."

Conover, 2013

Here there is clearly the use of an analogy – as a black hole is not the kind of thing that has actual hair. This would seem to be an example of a journalist creating an analogy (just as a science teacher would) to help 'make the unfamiliar familiar' to her readers:

just as

dogs with lots of hair need to shed some ready for the warmer weather (a reference to a familiar everyday situation)

so, too, do

black holes (no so familiar to most people) need to lose their hair…

(Read about making the unfamiliar familiar)

But hair?

Surely a better analogy would be along the lines that just as dogs with lots of hair need to shed some ready for the warmer weather, so to do black holes need to lose their magnetic fields…

An analogy is used to show a novel conceptual structure (here, relating to magnetic fields around black holes) maps onto a more familiar, or more readily appreciated, one (here, that a shaggy dog will shed some of its fur). A teaching analogy may not reflect a deep parallel between two systems, as its function may be just to introduce an abstract principle.

(Read about science analogies)

Why talk of black holes having 'hair'?

Conover did not invent the 'hair' reference for her ScienceNews piece – rather she built her analogy on  a term used by the scientists themselves. Indeed, the title of the cited research journal article was "Magnetic Hair and Reconnection in Black Hole Magnetospheres", and it was a study exploring the consequences of the "no-hair theorem" – as the authors explained in their abstract:

"The no-hair theorem of general relativity states that isolated black holes are characterized [completely described] by three parameters: mass, spin, and charge."

Bransgrove, Ripperda & Philippov, 2021

However, some black holes "are born with magnetic fields" or may "acquire magnetic flux later in life", in which case the fields will vary between black holes (giving an additional parameter for distinguishing them). The theory suggests that these black holes should somehow lose any such field: that is, "The fate of the magnetic flux (hair) on the event horizon should be in accordance with the no-hair theorem of general relativity" (Bransgrove, Ripperda & Philippov, 2021: 1). There would have to be a mechanism by which this occurs (as energy will be conserved, even when dealing with black holes).

So, the study was designed to explore whether such black holes would indeed lose their 'hair'.  Despite the use of this accessible comparison (magnetic flux as 'hair'), the text of the paper is pretty heavy going for someone not familiar with that area of science:

"stationary, asymptotically flat BH spacetimes…multipole component l of a magnetic field…self-regulated plasma…electron-positron discharges…nonzero stress-energy tensor…instability…plasmoids…reconnection layer…relativistic velocities…highly magnetized collisionless plasma…Lundquist number regime…Kerr-schild coordinates…dimensionless BH spin…ergosphere volume…spatial hypersurfaces…[…and so it continues]"

(Bransgrove, Ripperda & Philippov, 2021: 1).

"Come on Harry, you know full well that 'the characteristic minimum plasma density required to support the rotating magnetosphere is the Goldreich-Julian number density' [Bransgrove, Ripperda & Philippov, 2021: 2], so hand me that hyperspanner."
Image from Star Trek: Voyager (Paramount Pictures)

Spoiler alert

I do not think I will spoil anything by revealing that Bransgrove and colleague conclude from their work that "the no-hair theorem holds": that there is a 'balding process' – the magnetic field decays ("all components of the stress-energy tensor decay exponentially in time"). If any one reading this is wondering how they did this work, given that  most laboratory stores do not keep black holes in stock to issue to researchers on request, it is worth noting the study was based on a computer simulation.

That may seem to be rather underwhelming as the researchers are just reporting what happens in a computer model, but a lot of cutting-edge science is done that way. Moreover, their simulations produced predictions of how the collapsing magnetic fields of real black holes might actually be detected in terms of the kinds of radiation that should be produced.

As the news item explained matters:

Magnetic reconnection in balding black holes could spew X-rays that astronomers could detect. So scientists may one day glimpse a black hole losing its hair.

Conover, 2013

So, we have hairy black holes that go through a balding process when they lose their hair – which can be tested in principle because they will be spewing radiation.

Balding is to hair, as…

Here we have an example of an analogy for a scientific concept. Analogies compare one phenomenon or concept to another which is considered to have some structural similarity (as in the figure above). When used in teaching and science communication such analogies offer one way to make the unfamiliar familiar, by showing how the unfamiliar system maps in some sense onto a more familiar one.

hair = magnetic field

balding = shedding the magnetic field

Black holes are expected to be, or at least to become, 'hairless' – so without having magnetic fields detectable from outside the event horizon (the 'surface' connecting points beyond which everything, even light, is unable to 'escape' the gravitational field and leave the black hole). If black holes are formed with, or acquire, such magnetic fields, then there is expected to be a 'balding' process. This study explored how this might work in certain types of (simulated) black holes – as magnetic field lines (that initially cross the event horizon) break apart and reconnect. (Note that in this description the magnetic field lines – imaginary lines invented by Michael Faraday as a mental tool to think about and visualise magnetic fields – are treated as though they are real objects!)

Some such comparisons are deliberately intended to help scientists explain their ideas to the public – but scientists also use such tactics to communicate to each other (sometimes in frivolous or humorous ways) and in these cases such expressions may do useful work as short-hand expressions.

So, in this context hair denotes anything that can be detected and measured from outside a black hole apart form its mass, spin, and charge (see, it is much easier to say 'hair')- such as magnetic flux density if there is a magnetic field emerging from the black hole.

A dead metaphor?

In the research paper, Bransgrove, Ripperda and Philippov do not use the 'hair' comparison as an analogy to explain ideas about black holes. Rather they take the already well-established no-hair theorem as given background to their study ("The original no-hair conjecture states that…"), and simply explain their work in relation to it  ("The fate of the magnetic flux (hair) on the event horizon should be in accordance with the no-hair theorem of general relativity.")

Whereas an analogy uses an explicit comparison (this is like that because…), a comparison that is not explained is best seen as a metaphor. A metaphor has 'hidden meaning'. Unlike in an analogy, the meaning is only implied.

  • "The no-hair theorem of general relativity states that isolated black holes are characterized by three parameters: mass, spin, and charge";
  • "The original no-hair conjecture states that all stationary, asymptotically flat BH [black hole] spacetimes should be completely described by the mass, angular momentum, and electric charge"

(Read adbout science metaphors)

Bransgrove and colleagues do not need to explain why they use the term 'hair' in their research report as in their community it has become an accepted expression where researchers already know what it is intended to mean. We might consider it a dead metaphor, an expression which was originally used to imply meaning through some kind of comparison, but which through habitual use has taken on literal meaning.

Science has lots of these dead metaphors – terms like electrical charge and electron spin have with repeated use over time earned their meanings without now needing recourse to their origins as metaphors. This can cause confusion as, for example, a learner may  develop alternative conceptions about electron spin if they do not appreciate its origin as a metaphor, and assumes an electron spins in the same sense as as spinning top or the earth in space. Then there is an associative learning impediment as the learner assumes an electron is spinning on its axis because of the learner's (perfectly reasonable) associations for the word 'spin'.

The journalist or 'science writer' (such as Emily Conover), however, is writing for a non-specialist readership, so does need to explain the 'hair' reference.  So, I would characterise the same use of the terms hair/no-hair and balding as comprising a science analogy in the news item, but a dead metaphor in the context of the research paper. The meaning of language, after all, is in the mind of the reader.

Work cited:

Excavating a cognitive dinosaur

Keith S. Taber

Filling-in; and digging-out a teaching analogy

Is the work of cognition like the work of a palaeontologist? (Image by Brenda Geisse from Pixabay)

I like the reflexive nature of this account – of someone reconstructing an analogy

about how cognition reconstructs coherent wholes from partial, fragmented data

from a partial, fragmented memory representation.

I was reading something about memory function that piqued my interest in an analogy:

"Neisser, using an analogy initially developed by Hebb (1949) to characterize [sic] perception, likened the rememberer to a paleontologist who attempts to reconstruct a dinosaur from fragmentary remains: 'out of a few stored bone chips, we remember a dinosaur'…"

Schacter, 1995, p.10

I was interested enough to look up the original use of this analogy (as I report below).

This links to three things that have separately interested me:

  • the nature of memory
  • the constructivist account of learning and cognition
  • using analogies in teaching and comunicating science

The nature of our memories

I have long been interested in what memory is and how it works – and its role in academic learning (Taber,  2003). In part this perhaps derives from the limits of my own memory – I have been reasonably successful academically, but have never felt I had a good memory (and I seem to get more 'absent minded' all the time). This interest grew as it became clearer to me that our memory experiences seem to be quite different – my late wife Philippa would automatically and effortlessly remember things  in a way that that seemed to me to be a kind of superpower. (She was once genuinely surprised that I could not picture what a family member had been wearing on arriving at a family event years before, whereas I thought I was doing pretty well to even remember I had been there.) Now that neurodiversity is widely recognised, it seems less surprising that we do not all experience memory in the same way.

A lot of people, however, understand memory in terms of a kind of folk-model (that is, a popular everyday account which does not match current scientific understanding) – along the lines that we put information into a memory store, where – unless it gets lost and we forget – we can later access it and so remember what it was that we committed to memory. Despite the ubiquity of that notion, research suggests that is not really how memory functions. We might say that this is a common alternative conception of how memory works.

(Read about 'Memory')

The constructive nature of memory

Schacter was referring back to a tradition that began a century ago when Bartlett carried out a series of studies on memory. Bartlett (1932/1995) would, for example, expose people to a story that was unfamiliar to his study participants, and then later ask them to retell as much of the story as they could remember. As might be expected, some people remembered more details than others.

What perhaps was less predictable at the time was the extent to which people included in their retelling details that had not been part of the original story at all. These people were not deliberately embellishing or knowingly guessing, but reporting, as best they could, what their memory suggested had been part of the original story.

People who habitually exhibit this 'confabulation' to an pathological degree (perhaps remembering totally fantastic things that clearly could not be true) are recognised as having some kind of problem, but it transpires this is just an extreme of something that is normal behavior. Remembering is not the 'pulling something out of storage' that we may experience it as – as actually what we remember is more like a best guess based on insufficient data (but a guess made preconsciously, so it appears in our conscious minds as definitive) than a pristine copy of an original experience. Memory is often more a matter of constructing an account from the materials at hand than simply reading it out from something stored.

Thus the analogy. Here is some wider context for the quote presented above:

"The publication of Neisser's (1967) important monograph on cognitive psychology rekindled interest in Bartlett's ideas about schemas and reconstructive memory. According to Neisser, remembering the past is not a simple matter of reawakening a dormant engram or memory trace; past events are constructed by using preexisting knowledge and [schemata] to piece together whatever fragmentary remains of the initial episode are available in memory. Neisser, using an analogy initially developed by Hebb (1949) to characterize [sic] perception, likened the rememberer to a paleontologist who attempts to reconstruct a dinosaur from fragmentary remains: 'out of a few stored bone chips, we remember a dinosaur' (1967, p.285). In this view, all memories are constructions because they include general knowledge that was not part of a specific event, but is necessary to reconstruct it. The fundamentally constructive nature of memory in turn makes it susceptible to various kinds of distortions and inaccuracies. Not surprisingly, Neisser embraced Bartlett's observations and ideas about the nature of memory."

Schacter, 1995, p.10

These ideas will not seem strange to those who have studied science education, a field which has been strongly influenced by a 'constructivist' perspective on learning. Drawing on learning science research, the constructivist perspective focuses on how each learner has to build up their own knowledge incrementally: it is not possible for a teacher to take some complex technical knowledge and simply transfer it (or copy it) to a learner's mind wholesale.

(Read more about constructivism in education)

Excavating the analogy: what did Hebb actually say?

Hebb is remembered for his work on understanding the brain in terms of neural structures – neurons connected into assemblies through synapses.  His book 'The Organization of Behavior' has been described as "one of the most influential books in Psychology and Neuroscience" (Brown, 2020: 1).

Tachistoscope Source: Science Museum Group (This image is released under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 Licence)

The analogy referred to by Schacter was used by Hebb in describing perception. He discussed studies using a tachistoscope, an instrument for displaying images for very brief periods. This could be used to show an image to a person with an exposure insufficient for them to take in all the details,

"…the pattern is perceived, first, as a familiar one, and then with something missing or something added. The something, also, is familiar; so the total perception is a mélange of the habitual.

The subject's reports [make it] clear that the subject is not only responding to the diagram as a whole; he perceives its parts as separate entities, even though presentation is so brief. Errors are prominent, and such as to show that all the subject really perceives–and then only with rough accuracy–is the slope of a few lines and their direction and distance from one another"

Hebb, 1949: pp.46-47

That is, the cognitive system uses the 'clues' available from the incomplete visual data to build  (in effect) a hypothesis of what was seen, based on correspondences between the data actually available and familiar images that match that limited data. What the person becomes consciously aware of 'seeing' is not actually a direct report from the visual field of the presented image, but a constructed image that is a kind of conjecture of what might have been seen – 'filling-in' missing data with what seems most likely based on past visual experiences.

Cognitive scientist Annette Karmiloff-Smith developed the concept of 'representational redescription' as a way of describing how initially tacit knowledge could eventually become explicit. She suggested that "intra-domain and inter-domain representational relations are the hallmark of a flexible and creative cognitive system" (Karmiloff-Smith,1996: 192). The gist was that the brain is able to re-represent its own internal representations in new forms with different affordances.

An loose analogy might be someone who takes a screenshot when displaying an image from the JPEG photo collection folder on the computer, opens the screenshot as a pdf file, and then adds some textual annotations before exporting the file to a new pdf. The representation of the original image is unchanged in the system, but a new representation has been made of it in a different form, which has then been modified and 'stored' (represented) in a different folder.

Hebb was describing how a representation of visual data at one level in the cognitive system has been represented elsewhere in the system (representational redescription?) at a level where it can be mentipulated by 'filling-in'.

Hebb then goes on to use the analogy:

"A drawing or a report of what is seen tachistoscopically is not unlike a paleontologist's reconstruction of early man from a tooth and a rib. There is a clear effect of earlier experience, filling in gaps in the actual perception, so that the end result is either something familiar or a combination of familiar things–a reconstruction on the basis of experience."

Hebb, 1949: p.47

Teaching analogies

Hebb was writing a book that can be considered as a textbook, so this can be seen as a teaching analogy, although such analogies are also used in communicating science in other contexts.

(Read about Science analogies)

Teaching is about making the unfamiliar familiar, and one way we do that is by saying that 'this unfamiliar thing you need to learn about is a bit like this other thing that you already know about'. Of course, when teaching in this way we need to say in what way there is an analogy, and it may also be important to say in what ways the two things are not alike if we do not want people to map across irrelevant elements (i.e., to develop 'associative' learning impediments).

(Read about Making the unfamiliar familiar)

Hebb is saying that visual perception is often not simply the detection of a coherent and integral image, but is rather a construction produced by building upon the available data to construct a coherent and integral image. In extremis, a good deal may be made of very little scraps of input – akin to a scientist reconstructing a model of a full humanoid body based on a couple of bits of bone or tooth.

Hebb's analogy

There are examples where palaeontologists or anthropologists have indeed suggested such complete forms based on a few fossil fragments as data. This is only possible because of their past experiences of meeting many complete forms, and the parts of which they are made. (And of course, sometimes other scientists completely disagree about their reconstructions!)

An exscientific analogy?

Often in teaching science we use teaching analogies that compare an unfamiliar scientific concept to some familiar everyday phenomenon – perhaps a reaction profile is a bit like a roller-coaster track. Perhaps we could call these adscientific analogies as the meaning is transferred to the scientific concept from the everyday.

Sometimes, however, familiar scientific phenomena or ideas are used as the source – as here. Perhaps these could be called exscientific analogies as the meaning is taken from the science concept and applied elsewhere.

Developing the palaeontology analogy

So, Hebb had originally used the palaeontology analogy in the context of discussing perception. When I looked into how Neisser had used the comparison in his "important monograph on cognitive psychology" I found he had developed the analogy, returning to it at several points in his book.

Do we analyse what we attend to?

Neisser's first reference was also in relation to perception, rather than memory. Neisser argued that before we can attend to part of a scene there must already have been the operation of "preattentive mechanisms, which form segregated objects"  from which we can select what to attend to. These processes might be referred to as analyses:

"…the detailed properties and features that we ordinarily see in an attended figure…arise…only because part of the input was selected for attention and certain operations then performed on it. Neither the object of analysis nor the nature of the analysis is inevitable, and both may vary in different observers and at different times."

Neisser, 1967, p.94

But Neisser was not sure this really was 'analysis', which he understood as drawing on another (what I labelled above) exscientific analogy:

"The very word 'analysis' may not be apt. It suggests an analogy with chemistry: a chemist 'analyses' unknown substances to find out what they 'really' are."

Neisser, 1967, p.94

Rather than refer to analysis, we could draw on  Hebb's palaeontological analogy:

"More appropriate…is Hebb's (1949, p.47) comparison of the perceiver with a paleontologist, who carefully extracts a few fragments of what might be bones from a mass of irrelevant rubble and 'reconstructs' the dinosaur that will eventually stand in the Museum of Natural History. In this sense it is important to think of focal attention as a constructive, synthetic activity rather than as purely analytic. One does not simply examine the input and make a decision; one builds an appropriate visual object."

Neisser, 1967, p.94

[If it helps to have some examples to reflect upon this account of perception, you may find it useful to look at some images that may require careful interpretation.]

Neisser draws upon the analogy repeatedly in developing his account of perception:

"Such emotion-flooded experiences [as 'physiognomic' perception: 'Everyone has perceived such traits as suppressed anger in a face, gaiety in a movement, or peaceful harmony in a picture'] can be thought of as the result of particular kinds of construction. The same fragments of bone that lead one paleontologist to make an accurate model of an unspectacular creature might lead another, perhaps more anxious or more dramatic, to 'reconstruct' a nightmarish monster." (pp.96-97)

"To 'direct attention' to a figure is to attempt a more extensive synthesis of it. Of course, synthesis presupposes some prior analysis, as the paleontologist must have some fragments of bone before he can build his dinosaur…" (p.103)

"Recognition, whether of spelling patterns or words as wholes, must be mediated by relevant features, as meaningless in themselves as the bone chips of the paleontologist." (p.114)

"The process of figural synthesis does not depend only on the features extracted from the input, just as the dinosaur constructed by a paleontologist is not based only on the bone chips he has found. Equally important is the kind of perceptual object the perceiver is prepared to construct. The importance of set and context on the perception of words has been demonstrated in a great many experiments." (pp.115-116)

Neisser, 1967

And as with perception, so memory…

When Neisser discusses memory he uses a kind of double analogy – suggesting that memory is a bit like perception, which (as already established) is a bit like the work of the palaeontologist:

"Perception is constructive, but the input information often plays the largest single role in determining the constructive process. A very similar role, it seems to me, is played by the aggregate of information stored in long-term memory.

This is not to say that the stimuli themselves are copied and stored; far from it. The analogy being offered asserts only that the role which stored information plays in recall is like the role which stimulus information plays in perception….The model of the paleontologist, which was applied to perception and focal attention in Chapter 4, applies also to memory: out of a few stored bone chips, we remember a dinosaur….one does not recall objects or responses simply because traces of them exist in the mind, but after an elaborate process of reconstruction, (which usually makes use of relevant stored information).

What is the information – the bone chips – on which reconstruction is based? The only plausible possibility is that it consists of traces of prior processes of construction. There are no stored copies of finished mental events, like images or sentences, but only traces of earlier constructive activity."

Neisser, 1967, p.285
Fleshing-out the metaphor

Neisser then pushes the analogy one step further, by pointing out that the 'fleshed-out' model of a dinosaur in the museum may be constructed in part based on the fossil fragments of bones, but those fragments themselves do not form part of the construction (the model). The bones are used as referents in building the skeletal framework (literally, the skeleton) around which the model will be built, but the model is made from other materials (wood, steel, fibreglass, whatever) and the fossil fragments themselves will be displayed separately or perhaps filed away in a drawer in the museum archives. (As in the representational redescription model – the original representation is redescribed at another level of the system.)

"The present proposal is, therefore, that we store traces of earlier cognitive acts, not of the products of those acts. The traces are not simply 'revised' or 'reactivated' in recall; instead, the stored fragments are used as information to support a new construction. It is as if the bone fragments used by the paleontologist did not appear in the model he builds at all – as indeed they need not, if it to represent a fully fleshed-out skin-covered dinosaur. The bones can be thought of, somewhat loosely, as remnants of the structure which created and supported the original dinosaur, and thus as sources of information about how to reconstruct it."

Neisser, 1967, pp.285-286

Neisser's development of Hebb's analogy

The head palaeontologist?

A final reference to the analogy is used when Neisser addresses the question of the cognitive executive: the notion that somewhere in the cognitive system there is something akin to an overseer who direct operations:

"Who does the turning, the trying, and the erring" Is there a little man in the head, a homonculus, who acts the part of the paleontologist vis-à-vis the dinosaur? p.293

Neisser, 1967, p.293

The homonculus can be pictured as a small person sitting in the brain's control room, for example, viewing the images being projected from the visual input.

It is usually considered this is a flawed model (potentially lading to an infinite regress), a failure to take a systemic view of the cognitive system. It is the system which functions and leads to our conscious experience of perceiving, attending, making decisions, planning, remembering, and so forth. Whilst there are specialist components (modules) including for the coordination of the system, there is not a discrete controller overlaying the system as a whole who is doing the seeing, hearing, thinking, etcetera based on outputs from processing by the system.

Here the homonculus would like an authority that the palaeontologist turned to in order to decide how to build her model: raising the question of how does that expert know, and who would they, in turn, ask?

Why change Hebb's orignal analogy?

Altohugh Neisser refers to the analogy as being that used by Hebb, he modifies it. A tooth and rib become fragments of bone, and the early man becomes a dinosaur. Whether the shift from the reconstruction of an early hominid to the reconstruction of a terrible lizard was a deliberate one (for greater effect? because Neisser thought it would be more familiar to his readers?) or not I do not know. The phrasing suggests that Neisser thought he was applying Hebb's original comparison – so I suspect this is how he recalled the analogy.

Perhaps Neisser had regularly used the analogy in his teaching, in which case it may have become so familiar to him that he did not feel the need to check the original version. That is, perhaps he was correctly remembering how he had previously misremembered the original analogy. That is not fanciful, as memory researchers suggest this is something that is very common. Each time we access a memory the wider representational context becomes modified by engagement with it.

That is, if what is represented (in 'long-term memory'*) is indeed "traces of prior processes of construction…traces of earlier constructive activity" then each time a 'memory' is experienced, by being constructed based on what is represented ('in memory'*), new traces of that process of constructing the memory are left in the system.

It is possible over the years to be very convinced about the accuracy of a distorted memory that has been regularly reinforced. (The extent to which this may in part be the origin of many wars, feuds, and divorces might be a useful focus for research?)

So perhaps Neisser had represented in his long-term memory the analogy of a palaeontologist with a few fossil fragments, and when he sought to access the analogy, perhaps in a classroom presentation, the other elements were filled-in: the 'tooth and rib' became 'a few fragments of what might be bones' and the 'early man' become 'a dinosaur' – details that made sense of the analogy in terms familiar to Neisser.

The account of cognition that Hebb, Neisser and Schater were presenting would suggest that if this had been the case then for Neisser there would be no apparent distinction between the parts of Hebb's analogy that Neisser was remembering accurately, and the parts his preconscious mind had filled-in to construct a coherent analogy. I like the reflexive nature of this account – of someone reconstructing an analogy about how cognition reconstructs coherent wholes from partial, fragmented data – from a partial, fragmented memory representation.

 Sources cited:
  • Bartlett, F. C. (1932/1995). Remembering: A study in experimental and social psychology Cambridge: Cambridge University Press.
  • Brown, R. E. (2020). Donald O. Hebb and the Organization of Behavior: 17 years in the writing. Molecular Brain, 13(1), 55. doi:10.1186/s13041-020-00567-8
  • Hebb, D. O. (1949). The Organisation of Behaviour. A neuropsychological theory. New York: John Wiley & Sons, Inc.
  • Karmiloff-Smith, A. (1996). Beyond Modularity: A developmental perspective on cognitive science. Cambridge, Massachusetts: MIT Press.
  • Neisser, U. (1967). Cognitive Psychology. New York: Appleton-Century-Crofts.
  • Schacter, D. L. (1995). Memory distortion: history and current status. In D. L. Schacter (Ed.), Memory Distortion. How minds, brains, and societies reconstruct the past (pp. 1-43). Cambridge, Massachusetts: Harvard University Press.
  • Taber, K. S. (2003) Lost without trace or not brought to mind? – a case study of remembering and forgetting of college science, Chemistry Education: Research and Practice, 4 (3), pp.249-277. [Free access]

* terms like 'in memory' and 'in long-term memory' may bring to mind the folk-notion of memory as somewhere in the brain where things are stored away, whereas it is probably better to think of the brain as a somewhat plastic processing system which is constantly being modified by its own functioning. The memory we experience is simply the outcome of active processing** in part of the system that has previously been modified by earlier mental activity (** active processing which is in turn itself further modifying the system).

Scientific errors in the English National Curriculum

Keith S. Taber

I am writing this open letter to the Institute of Physics and the Royal Society of Chemistry to request that as Learned Societies with some influence with government (perhaps limited, but certainly vastly more than an academic) the Societies might ask the Department for Education to correct two basic errors of science in the National Curriculum for England which is set out as the basis for teaching school age learerns and for developing public examinations specifications and papers.
The two errors relate to (a) the misuse of scientific terminology (the word substance) and (b) a failure of logic (in a reference to conservation of energy). As you will no doubt be aware, the original published version of this iteration of the programmes of study for science in the English National Curriculum included some basic errors (incorrect physics formulae) that received wide publicity and which were quickly amended. Despite some other issues also getting early attention, these other problems have never been addressed. One more complex issue that I strongly feel deserves addressing, but which would would require considerable redrafting, is the confused and incoherent treatment of the nature of chemical reactions across the secondary phase (Key Stages 3 and 4). I have raised these issues at various times, and have published a scholarly analysis of these problems .Whilst I obviously did not expect an article in an academic journal to directly impact policy, I thought this could be a 'springboard' to then approach government. I have contacted the relevant ministers (the Rt Hon Gavin Williamson CBE MP, Secretary of State for Education and the Rt Hon Nick Gibb MP, Minister of State for School Standards), and in response to instructions to refer this issue to the Department for Education website, I did so. My comments have been noted, but I was informed
"there are no current plans to review the curriculum".
Whilst I accept that any detailed re-working of the curriculum is not imminent, I do think the Department could still instigate minor corrections to errors which are published on the government's website, and then consequently repeated by the examination authorities, the examination boards and even individual school websites. Correcting these (surely, embarrassing) errors would require very little effort. The first error I refer to is the incorrect use of the term 'substance'. In science, the term substance has a fairly specific meaning. Although, as with many science concepts, there may be some discussion over precise definitions and demarcations, there is general agreement at the level at which the term would be used in introductory science at school level. In the primary stages of the English National Curriculum for Science we read that Y5 learners should be
"taught to…explain that some changes result in the formation of new materials [sic], and that this kind of change is not usually reversible, including changes associated with burning and the action of acid on bicarbonate of soda".
A better term here would be 'substances', not 'materials' (although this is more a mater of the wording being imprecise than incorrect). However in relation to Y4 learners there is a reference to
"exploring the effect of temperature on substances [sic] such as chocolate, butter, cream"
none of which are substances as the word is used in science.This is a misuse of the term 'substance'. So whereas in secondary school, learners are taught to distinguish the meanings of 'material' and the more specific 'substance', it seems these terms are being used interchangeably in the National Curriculum specification itself. The other issue relates to the statement (in the Key Stage 4 specification) that
"energy is conserved in chemical reactions so can therefore be neither created nor destroyed".
To my reading this suggests a blatant error of logic, which I can only assume does not reflect scientific ignorance by the person drafting the document – but more likely is a typographic error that has never been corrected. Conservation of energy is a general (universal) principle, and its more specific application to chemical reactions as one class of changes is then subsumed under that principle. I have long assumed that what had been intended (but mistyped) was either "energy is conserved in chemical reactions BECAUSE it can be neither created nor destroyed" or "energy CAN be neither created nor destroyed SO THEREFORE is conserved in chemical reactions" – that is, the logic has been completely reversed in the curriculum document. I have recently realised that there is a third possibility: that this statement is not meant as an explanation (of energy conservation in reactions under a more general principle) but as a definition, along the lines "energy is conserved in chemical reactions WHICH MEANS THAT IT CAN be neither created nor destroyed". Whatever was meant, the current wording implies a logical non sequitur, and should, surely, be corrected. I would hope you might agree that these kinds of errors should not be included in what teachers are asked to teach, students to learn, and examining boards to assess; and that when a suitable opportunity arrises you might make appropriate representations regarding the desirability of corrections being made. Your sincerely, Dr Keith S.Taber Emeritus Professor of Science Education (I have had constructive replies from both the RSC and IoP)

We can't handle the scientific truth

"If the muscles and other cells of the body burn sugar instead of oxygen…"

Do they think we cannot handle the scientific truth?

I should really have gone to bed, but I was just surfing the channels in case there was some 'must watch' programme I might miss, and I came across a screening of the film 'A few good men'. This had been a very popular movie at one time, and I seem to recall watching it with my late wife. I remembered it as an engaging film, and as an example of the 'courtroom drama' genre: but beyond that I could really only remember Tom Cruise as defence advocate questioning Jack Nicholson's as a commanding officer – and the famous line from Nicholson – "You can't handle the truth!".

This became something of a meme – I suspect now there are a lot of people who 'know' and use that line, who have never even seen the film and may not know what they are quoting from.

So, I  though I might watch a bit, to remind myself what the actual case was about. In brief, a marine stationed at the U.S. Guantánamo Bay naval base and detention camp had died at the hands of two of his comrades. They had not intended to kill, but admitted mistreating him – their defence was they were simply obeying orders in subjecting a colleague who was not measuring up, and was letting the unit down, to some unpleasant, but ultimately (supposedly) harmless, punishment.

The film does not contain a lot of science, but what struck me was the failure to get some science that was invoked right.  I was so surprised at what I thought I'd heard being presented as science, that I went back and replayed a section, and I then decided to see if I  could find the script (by Aaron Sorkin*, screenplay adapted from his own theatre play) on the web, to see if what was said had actually been written into the script.

One of the witnesses is a doctor who is asked by the prosecuting counsel to explain lactic acidosis.

Burning sugar instead of oxygen?

The characters here are:

Capt. Jack Ross (played by Kevin Bacon) the prosecuting counsel,

Dr. Stone (Christopher Guest) and

 

 

 

Lt. Daniel Kaffee (Cruise's character).

On direct examination:

Ross: Dr. Stone, what's lactic acidosis?

Stone: If the muscles and other cells of the body burn sugar instead of oxygen, lactic acid is produced. That lactic acid is what caused Santiago's lungs to bleed.

Ross: How long does it take for the muscles and other cells to begin burning sugar instead of oxygen?

Stone: Twenty to thirty minutes.

Ross: And what caused Santiago's muscles and other cells to start burning sugar? [In the film, the line seems to be: And what caused this process to be speed up in Santiago's muscles?]

Stone: An ingested poison of some kind.

Later, under cross-examination

Kafee: Commander, if I had a coronary condition, and a perfectly clean rag was placed in my mouth, and the rag was accidentally pushed too far down, is it possible that my cells would continue burning sugar after the rag was taken out?

Stone: It would have to be a very serious condition.

What?

If a student suggested that lactic acid is produced when the muscles burn sugar instead of oxygen we would likely consider this an alternative conception (misconception). It is, at best, a clumsy phrasing, and is simply wrong.

Respiration

Metabolism is a set of processes under very fine controls, so whether we should refer to metabolism as burning or not, is a moot point. Combustion tends to be a vigorous process that is usually uncontrolled. But we can see it as a metaphor: carbohydrates are 'burnt' up in the sense that they undergo reactions analogous to burning.

But burning requires oxygen (well, in the lab. we might burn materials in chlorine, but, in general, and in everyday life, combustion is a reaction with oxygen), so what could burning oxygen mean?

In respiration, glucose is in effect reacted with oxygen to produce carbon dioxide and water. However, this is not a single step process, but a complex set of smaller reactions – the overall effect of which is

glucose + oxygen → carbon dioxide + water

Breaking glucose down to lactic acid also acts as an energy source, but is no where near as effective. Our muscles can undertake this ('anaerobic') process when there is insufficient oxygen supply –  for example when undertaking high stamina exercise – but this is best seen as a temporary stop-gap, as lactic acid build up causes problems (cramp for example) – even if not usually death.

Does science matter?

Now clearly the science is not central to the story of 'A few good men'. The main issues are (factual)

  • whether the accused men were acting under orders;

(ethical)

  • the nature of illegal orders,
  • when service personal should question and ignore orders (deontology) given that they seldom have the whole picture (and in this film one of the accused men is presented as something of a simpleton who viewer may suspect should not be given much responsibility for decision making),
  • whether it is acceptable to use corporal or cruel punishment on an under-performing soldier (or marine) given that the lives of many may depend upon their high levels of performance (consequentialism, or perhaps pragmatics)…

There is also a medical issue, regarding whether the torture of the soldier was the primary cause of death, or whether there was an underlying health issue which the medical officer (Stone) had missed and which might also explain the poor performance. [That is a theme which featured large in a recent very high profile real murder case.]

Otherwise the film is about the characters of, and relationships among, the legal officers. Like most good films – this is film about people, and being human in the world, and how we behave towards and relate to each other.

The nature of lactic acidosis is hardly a key point.

But if it is worth including in the script as the assumed cause of death, and its nature relevant – why not get the science right?

Perhaps, because science is complicated and needs to be simplified for the cinema-goer who, after all, wants to be entertained, not lectured?

Perhaps there is no simple account of lactic acidosis which could be included in the script without getting technical, and entering into a long and complicated explanation.

In teaching science…

But surely that is not true. In teaching we often have to employ simplifications which ignore complexity and nuance for the benefit of getting the core idea across to learners. We seek the optimal level of simplification that learners can make good sense of, but which is true to the core essence of the actual science being discussed (it is 'intellectually honest') and provides a suitable basis for later more advanced treatments.

It can be hard to find that optimum level of simplification – but I really do not think that explaining lactic acidosis as burning sugar instead of oxygen could be considered a credit-worthy attempt.

Dr. Stone, can we try again?

What about, something like:

Dr. Stone, what's lactic acidosis?

It occurs when the body tissues do not have sufficient oxygen to fully break down sugar in the usual way, and damaging lactic aid is produced instead of carbon dioxide and water.

I am sure there are lots of possible tweaks here. The point is that the script did not need to go into a long medical lecture, but by including something that was simply nonsensical, and should be obviously wrong to anyone who had studied respiration at school (which should be everyone who has been to school in the past few decades in many countries), it distracts, and so detracts, from the story.

All images from 'A few good men' (1992, Columbia Pictures)

 

 

 

 

 

 

 

 

 

 

* I see that ("acclaimed screenwriter") Aaron Sorkin is planning a new live television version of 'A Few Good Men' – so perhaps the description of lactic acidosis can be updated?

Thank you, BBC: I'll give you 4/5

BBC corrects cruel (to cats) scientific claim on its website

Keith S. Taber

I just got 80% on a science test for primary school children

I've just scored 4/5 (80%) on an on-line KS2 science test on the BBC (the British Broadcasting Corporation) educational website. 80% sounds quite good out of context, but I am a science teacher and KS2 is meant for 7-11 year olds.

The BBC awards me 4/5 for my primary level science knowledge about the states of matter

My defence is that the question I got wrong was ambiguous (but, as Christine Keeler might have said, I would say that).

I was actually getting round to checking on something from a while back.

In 2019 I came across something on the website that I thought was very misleading – and I complained to the BBC through their website form. I had an immediate, but generic response:

"Thank you for taking the time to send us your comments. We appreciate all the feedback we receive as it plays an important role in helping to shape our decisions.

This is an automated message (sorry that we can't reply individually) to let you know that we've read your comments and will report them overnight to staff across the BBC for them to read too (after removing any personal details). This includes our programme makers, commissioning editors and senior management.

Thanks again for contacting the BBC.

BBC Audience Services.

NB: Please do not reply to this email. It includes a reference number but comes from an automated account which is not monitored."

Email: 6th Sept., 2019

This kind of response is somewhat frustating. My complaint had been recieved, and would be passed on, but it looked like I would get no specific response (as presumably if my "comments" were to be reported to relevant staff "after removing any personal details", those staff would not be in a position to let me know if they were following up, dismissing, or simply ignoring, my comments.) Indeed, I never did get any follow up.

So, my intention was to check back after a decent period had elapsed (n.b., where does all the time go?) and see if anything had been changed in response to my complaint. Strictly, if there had been a change this could be because:

  • a) I complained
  • b) someone else/some other people complained (i.e., people who's complaints were taken more seriously than mine)
  • c) I was one of number of people who complained
  • d) material had been updated compleltely independently of any compaints

That is, I could not know if I personally had had any effect, BUT if the offending material (because as a chemist I was offended professionally, even if not personally) was still there then I would know my compaint had not been heeded.

So, I intended to check back; I expected to find no change (as pointing out blatant, basic, errors in the science in the English National Curriculum to government ministers did not have any effect, so the BBC…? ); and, if so, I thought of following up with an email or an old fashioned snail-mail … ("…yours, disgusted of Cambourne"*).

Well done, BBC

So, I am happy to publicly acknowledge that the BBC has changed its materials appearing under the heading 'What are the states of matter?'

The topic comprises of a short animation (with odd anthropomorphised {"guys"} geometric shapes handling examples of the states of matter: solid, liquid and gas); a series of bullet points on each state; a sorting task; and then the set of five objective (multiple choice) questions.

There are a number of issues with the examples used here, as discussed below. But the main focus of my complaint, a cartoon cat, has now been released from the indignity of being classified as a state of matter. Yes, a cat!

Limitations of the three states of matter model

The idea that matter can exist in three states is a pretty important foundation for a good deal of other science.

However there is big problem with the generality of the model. Basically it really applies to pure samples of substances: generally substances (not materials in general, and certainly not objects) exist as solids, liquids, or gases, depending on the conditions of temperature and pressure – although at high enough temperatures plasmas are formed (and theoretically when hot enough even the atomic cores, and eventually nuclei would break down – but those conditions are pretty extreme and not found in the typical home or classroom).

Examples of substances include water, salt, calcium carbonate, iron, mercury, hydrogen, graphite, carbon dioxide, sulphur… that is, elements and compounds. Of course, many of these are seldom met in pure form in everyday life outside school science labs.

Most materials that people come across are mixtures or composites. Mixtures often exist as solutions or suspensions – as gels or foams or emulsions – not as solids, liquids or gases.

This is probably why the terms 'solids', 'liquids' and 'gases' actually have two sets of meanings – the science or technical sense, and the everyday or 'life-world' sense. So milk is a liquid(everyday) as you can pour some into your tea cup and a block of wood is a solid(everyday) as it retains its shape and integrity as you nail it to another structure. But milk and wood are not substances – and so not liquid(scientific) or solid(scientific).

Does this matter? Yes, because if we are teaching children things in science lessons, it would be good to get the science right. A solid will melt at a distinct melting temperature to give a liquid which will boil at a distinct boiling temperature. Wood, for example, does not.

Wood is a complex material. It has gas pockets. It has (variable) moisture content, and the structure contains various compounds – lignin, cellulose, and many more. The response to heating reflects that complex constitution.

The BBC's examples of solids, liquids, and gases

The BBC website suggests examples of the three states of matter to introduce primary age students to the concept.

Animation:

Solids: block of ice, football

Lquids: water, honey

Gases: none are specified – animation shows the clouds (of liquid water droplets) forming around a kettle spout, and 'gas' put into in fizzy drinks is referenced.

A football is not solid, but usually air (a mixture of gases with some other components) contained in a plastic shell. (The voiceover refers simply to a 'ball', but the animation show a large ball with a traditional football pattern being used to do 'keepy uppies' by the cartoon character.)

Honey is not a liquid(scientific) but a complex mixture of sugars in solution. There is usually much more sugar than water. (So, arguably, it is more solid than liquid – but it is better to simply not consider it as either.) This is where I dropped a mark on the terminal test:

Two of the options are NOT liquids. Only one response gets credit in this test!
Web text:

The bullet points on the site list some further examples:

"Examples of solids include ice, wood and sand." (Ice and sand are solids(scientific).)

"Examples of liquids include water, honey and milk." (Only water is liquid(scientific) here.)

"Examples of gases include steam, helium and oxygen." (3/3, well done BBC!)

Sorting task:
The BBC website task invites children to sort cards showing objects into three categories. (What is that object on the front card meant to be?)

In the sorting task, children are asked to sort a number of examples shown on cards into solid, liquid, and gas:

The examples presented are air, a feather, helium, milk, a pencil, sea, steam, syrup, wood. Of these only helium and steam strictly meet the criteria for being a solid(scientific)/liquid(scientific)/gas(scientific). Yet, as suggested above, it is difficult to find genuine examples that are both scientifically correct and familiar to young children. Perhaps sea and air (at least materials) are closer approximations than a pencil or a feather ("solids retain their shape" – would a child using the website have handled a feather, and, if so, would it have retained its shape under child-handling?)

So, I still have reservations about this material, whilst acknowledging the need to balance scientific correctness with relevant (to children) examples. Strictly, some of the examples can be seen as encouraging children to get the science wrong. These things matter if only because children are learning things on this site that later in their school career will be judged as alternative conceptions and marked as wrong.

(Read 'Are plants solid?')

None the less, I am pleased that the BBC has at least decided to amend its sorting task, and remove the poor cat:

Which pile does the cat belong in? [This example has now been removed. Bravo.]

The website had previously been quite clear that putting the cat as anything other than solid was 'wrong'. It is classed as a solid even though a cat (like any animal) is (or would be if separated out into its constituent substances – and children should not try this at home) more water than anything else.

I had real trouble seeing how that example fitted with the criteria specified on the webpage:

"[Cats] stay in one place and can be held.

[Cats] keep their shape. They do not flow like liquids.

[Cats] always take up the same amount of space. They do not spread out like gases.

[Cats] can be cut or shaped."

Characteristics of solids, but perhaps not entirely true of cats?

* cf. the idiom 'disgusted of Tunbridge Wells' – referring to a hypothetical person who writes to media complaining about matters of concern.

Images used here are screenshots, copyright of the BBC – a publicly funded public service broadcaster.

Do nerve signals travel faster than the speed of light?

Keith S. Taber

I have recently posted on the blog about having been viewing some of the court testimony being made available to the public in the State of Minnesota v. Derek Michael Chauvin court case (27-CR-20-12646: State vs. Derek Chauvin).

[Read 'Court TV: science in the media']

Prof. Martin J. Tobin, M.D., Loyola University Chicago Medical Center

I was watching the cross examination of expert witness Dr Martin J. Tobin, Professor of Pulmonary and Critical Care Medicine by defence attorney Eric Nelson, and was intrigued by the following exchange:

Now you talked quite a bit about physics in your direct testimony, agreed?

Yes

And you would agree that physics, or the application of physical forces, is a constantly changing, er, set of circumstances.

I did not catch what you said.

Sure. You would agree with me, would you not, that when you look at the concept may be considered as the sum of all its associations.&lt;em&gt;Read about concepts&lt;/em&gt;&lt;br/&gt;</div>" href="https://science-education-research.com/reference/site-glossary/concepts/" target="_blank" data-mobile-support="0" data-gt-translate-attributes='[{"attribute":"data-cmtooltip", "format":"html"}]' tabindex='0' role='link'data-bgcolor="#e8e8e8"data-tcolor="#73874d">concepts of physics, these things are constantly changing, right?

Yeah, all of science is constantly changing.

Constant! I mean,

Yes.

in milliseconds and nanoseconds, right?

Yes.

And so if I put this much weight [Nelson demonstrating by shifting position] or this much weight [shifting position], all of the formulas [sic] and variations, will change from second to second, from millisecond to millisecond, nanosecond to nanosecond, agreed.

I agree.

Similarly, biology sort of works the same way. Right?

Yes.

My heart beats, my lungs breathe [sic], my brain is sending millions of signals to my body, at all times.

Correct.

Again, even, I mean, faster than the speed of light, right?

Correct.

Millions of signals every nanosecond, right?

Yes.

Day 9. 27-CR-20-12646: State vs. Derek Chauvin

Agreeing – but talking about different things?

The first thing that struck me here concerns what seems to me to be Mr Nelson and Dr Tobin talking at cross-purposes – that neither participant acknowledged (and so perhaps neither were aware of).

I think Nelson is trying to make an argument that the precise state of Mr George Floyd (who's death is at the core of the prosecution of Mr Chauvin) would have been a dynamic matter during the time he was restrained on the ground by three police officers (an argument being made in response to the expert's presentation of testimony suggesting it was possible to posit fairly precise calculations of the forces acting during the episode).

This seems fairly clear from the opening question of the exchange above:

Now you talked quite a bit about physics in your direct testimony, agreed? … And you would agree that physics, or the application of physical forces, is a constantly changing, er, set of circumstances.

However, Dr Tobin does not hear this clearly (there are plexiglass screens between them as COVID precautions, and Nelson acknowledges that he is struggling with his voice by this stage of the trial).

Nelson re-phrases, but actually says something rather different:

You would agree with me, would you not, that when you look at the concept may be considered as the sum of all its associations.&lt;em&gt;Read about concepts&lt;/em&gt;&lt;br/&gt;</div>" href="https://science-education-research.com/reference/site-glossary/concepts/" target="_blank" data-mobile-support="0" data-gt-translate-attributes='[{"attribute":"data-cmtooltip", "format":"html"}]' tabindex='0' role='link'data-bgcolor="#e8e8e8"data-tcolor="#73874d">concepts of physics, these things are constantly changing, right?

['These things' presumably refers to 'the application of physical forces', but if Dr Tobin did not hear Mr Nelson's previous utterance then 'these things' would be taken to be 'the concept may be considered as the sum of all its associations.&lt;em&gt;Read about concepts&lt;/em&gt;&lt;br/&gt;</div>" href="https://science-education-research.com/reference/site-glossary/concepts/" target="_blank" data-mobile-support="0" data-gt-translate-attributes='[{"attribute":"data-cmtooltip", "format":"html"}]' tabindex='0' role='link'data-bgcolor="#e8e8e8"data-tcolor="#73874d">concepts of physics'.]

So, now it is not the forces acting in a real world scenario which are posited to be constantly changing, but the concept may be considered as the sum of all its associations.&lt;em&gt;Read about concepts&lt;/em&gt;&lt;br/&gt;</div>" href="https://science-education-research.com/reference/site-glossary/concepts/" target="_blank" data-mobile-support="0" data-gt-translate-attributes='[{"attribute":"data-cmtooltip", "format":"html"}]' tabindex='0' role='link'data-bgcolor="#e8e8e8"data-tcolor="#73874d">concepts of physics. Dr Tobin's response certainly seems to make most sense if the question is understood in terms of the science itself being in flux:

Yeah, all of science is constantly changing.

Given that context, the following agreement that these changes are occurring "in milliseconds and nanoseconds" seems a little surreal, as it is not quite clear in what sense science is changing on that scale (except in the sense that science is continuing constantly – certainly not in the sense that canonical accounts of concept may be considered as the sum of all its associations.&lt;em&gt;Read about concepts&lt;/em&gt;&lt;br/&gt;</div>" href="https://science-education-research.com/reference/site-glossary/concepts/" target="_blank" data-mobile-support="0" data-gt-translate-attributes='[{"attribute":"data-cmtooltip", "format":"html"}]' tabindex='0' role='link'data-bgcolor="#e8e8e8"data-tcolor="#73874d">concepts shift at that pace: say, in the way Einstein's notions of physics came to replace those of Newton).

In the next exchange the original context Nelson had presented ("the application of physical forces, is … constantly changing") becomes clearer:

And so if I put this much weight [Nelson demonstrating by shifting position] or this much weight [shifting position], all of the formulas and variations, will change from second to second, from millisecond to millisecond, nanosecond to nanosecond, agreed.

I agree.

As a pedantic science teacher I would suggest that it is not the formulae of physics that change, but the values to be substituted into the system of equations derived from them to describe the particular event: but I think the intended meaning is clear. Dr Tobin is a medical expert, not a physicist nor a science teacher, and the two men appear to be agreeing that the precise configurations of forces on a person being restrained will constantly change, which seems reasonable. I guess that is what the jury would take from this.

If my interpretation of this dialogue is correct (and readers may check the footage and see how they understand the exchange) then at one point the expert witness was agreeing with the attorney, but misunderstanding what he was being asked about (how in the real world the forces acting are continuously varying, not how the concept may be considered as the sum of all its associations.&lt;em&gt;Read about concepts&lt;/em&gt;&lt;br/&gt;</div>" href="https://science-education-research.com/reference/site-glossary/concepts/" target="_blank" data-mobile-support="0" data-gt-translate-attributes='[{"attribute":"data-cmtooltip", "format":"html"}]' tabindex='0' role='link'data-bgcolor="#e8e8e8"data-tcolor="#73874d">concepts of science are constantly being developed). Even if I am right, this does not seem problematic here, as the conversation shifted to the intended focus quickly (an example of Bruner's 'constant transnational calibration' perhaps?).

However, this reminds me of interview</div><div class=glossaryItemBody>Research interviewing involves a class of techniques for collecting data based upon engaging informants in conversations with various levels of structuring&lt;em&gt;Read more about research interviews&lt;/em&gt;&lt;br/&gt;</div>" href="https://science-education-research.com/reference/site-glossary/interview/" target="_blank" data-mobile-support="0" data-gt-translate-attributes='[{"attribute":"data-cmtooltip", "format":"html"}]' tabindex='0' role='link'data-bgcolor="#e8e8e8"data-tcolor="#73874d">interviews with students I have carried out (and others I have listened to undertaken by colleagues), and of classroom episodes where teacher and student are agreeing – but actually are talking at cross purposes. Sometimes it becomes obvious to those involved that this is what has happened – but I wonder how often it goes undetected by either party. (And how often there are later recriminations – "but you said…"!)

Simplifying biology?

The final part of the extract above also caught my attention, as I was not sure what to make of it.

My heart beats, my lungs breathe, my brain is sending millions of signals to my body, at all times.

Correct.

Again, even, I mean, faster than the speed of light, right?

Correct.

Millions of signals every nanosecond, right?

Yes.

How frequently do our brains send out signals?

I am a chemistry and physicist, not a biologist so I was unsure what to make of the millions of signals the brain is sending out to the rest of the body every nanosecond.

I can certainly beleive that perhaps in a working human brain there will be billions of neutrons firing every nanosecond as they 'communicate' with each other. If my brain has something like 100 000 000 000 neurons then that does not seem entirely unreasonable.

But does the brain really send signals to the rest of the body (whether through nerves or by the release of hormones) at a rate of nx106/10-9 s-1 ("millions of signals every nanosecond"), that is,  multiples of 1015 signals per second, as Mr Nelson suggests and Dr Tobin agrees?

Surely not? Dr Tobin is a professor of medicine and a much published expert in his field and should know better than me. But I would need some convincing.

Biological warp-drives

I will need even more convincing that the brain sends signals to the body faster than the speed of light. Both nervous and hormonal communication are many orders of magnitude slower than light speed. The speed of light is still considered to be a practical limit on the motion of massive objects (i.e., anything with mass). Perhaps signals could be sent by quantum entanglement – but that is not how our nervous and endocrine systems function?

If Mr Nelson and Dr Tobin do have good reason to believe that communication of signals in the human body can travel faster than the speed of light then this could be a major breakthrough. Science and technology have made many advances by mimicking, or learning from, features of the structure and function of living things. Perhaps, if we can learn how the body is achieving this impossible feat, warp-drive need not remain just science fiction.

A criminal trial is a very serious matter, and I do not intend these comments to be flippant. I watched the testimony genuinely interested in what the science had to say. The real audience for this exchange was the jury and I wonder what they made of this, if anything. Perhaps it should be seen as poetic language making a general point, and not a technical account to be analysed pedantically. But I think it does raise issues about how science is communicated to non-experts in contexts such as courtrooms.

This was an expert witness for the prosecution (indeed, very much for the prosecution) who was agreeing with the defence counsel on a point strictly contrary to accepted science. If I was on a jury, and an expert made a claim that I knew was contrary to current well-established scientific thinking (whether the earth came into being 10 000 years ago, or the brain sends out signals that travel faster then the speed of light) this would rather undermine my confidence in the rest of their expert testimony.

 

 

 

Temperature is measuring the heat of something …

Keith S. Taber

Image by Peter Janssen from Pixabay 

Bill was a participant in the Understanding Science Project. Bill, then in Y7, was telling me about work he had done in his science class on the states of matter, and what happened to the particles that made up objects during a change of state. He suggested that "when a solid goes to a liquid, the heat gives the particles energy to spread about, and then when its a liquid, it's got even more energy to spread out into a gas". Later in the interview I followed up to find out what Bill understood by heat:

Now you mentioned earlier, something about heat. When you were talking about the experiment you did.

Yeah.

Yeah. So tell me about the heat again, what's, how does the heat get involved in this solids, liquids and gases?

When I heat, when heat comes to a solid, it will have, erm, a point where it will go down to a liquid,

Okay,

A melting points of the, the object.

Do you know what heat is? If you had a younger brother or sister, and they said to you, 'you are good at science, what's heat?'

I'm not sure how I can explain it, 'cause it's, it can be measured at different temperature, it can be measured at temperature, erm, by degrees Celsius, degrees Fahrenheit, and – I'm not really sure how I could explain what it is, but, I know it can be measured and changed.

So is it the same thing as temperature, do you think, or is it something different?

Erm, I think temperature is measuring the heat of something.

So they're related, they're to do with each other?

Yeah.

But they are not exactly the same?

No.

Bill appreciated that heat and temperature were not the same, but was not entirely clear on the relationship. Distinguishing between heat and temperature is a recognised challenge in teaching and learning physics.

We commonly introduce temperature as a measure of how hot or cold something is – which relates to phenomena that all students have experienced (even if our actual perception of temperature is pretty crude). Heating is a process, and heat is sometimes considered to be energy being transferred due to a difference of temperature (although energy is a very abstract notion and there is much discussion in science teaching circles about the best language to be used in teaching about energy).

Put simply, it is reasonable to suggest a very hot object would have a high temperature, but not that it contained a lot of heat. So, it is strictly wrong to say that "temperature is measuring the heat of something" (and it would be more correct, if not very technical, to say instead "temperature is measuring the hotness of something – how hot something is"). Perhaps the idea Bill wanted to express was more about the heat that one can feel radiating form a hot object (but likely that is an interpretation suggested by the canonical science use of 'heat'?)

This is one of those situations where a student has an intuition or idea which is basically along the right lines, in the sense of knowing there is an association or link, but strictly not quite right – so, an alternative conception. In a teaching situation it might be useful to know if a student actually has a firm conception that temperature measures the amount of heat, or (as seems to be the case with Bill) this is more a matter of using everyday language – which tends to be less precise and rigid than technical language – to express a vague sense. If a student has a firm notion that hot objects contain heat, and this is not identified and responded to, then this could act as a grounded learning impediment as it will likely distort how teaching is understood.

The teacher is charged with shifting learners away from their current ways of thinking and talking, towards using the abstractions and technical language of the subject, such as the canonical relationship between heat and temperature – and this often means beginning by engaging with the learners' ideas and language. Arguably the use of the term 'heat capacity' (and 'specific heat capacity') which might suggest something about the amount of heat something can hold, is unhelpful here.

.