The earth's one long-term objective

Scientist reveals what the earth has been trying to do

Keith S. Taber

Seismology – the study of the earth letting off steam? (Image by ELG21 from Pixabay)

"the earth has one objective, it has had one objective for four and half billion years, and that's…"

In our time

'In Our Time' is an often fascinating radio programme (and podcast) where Melvyn Bragg gets three scholars from a field to explain some topic to a general audience.

Imagine young Melvyn interrupting a physics teacher's careful exposition of why pV = 1/3nmc2 by asking how the gas molecules came to be moving in the first place.

The programme covers various aspects of culture.

BBC 'In our time'

I am not sure if the reason that I sometimes find the science episodes seem a little less erudite than those in the the other categories is:

  • a) Melvyn is more of an arts person, so operates at a different level in different topics;
  • b) I am more of a science person, so more likely to be impressed by learning new things in non-science topics; and to spot simplifications, over-generalisations, and so forth, in science topics.
  • c) A focus in recent years on the importance of the public understanding of science and science communication means that scientists may (often, not always) be better prepared and skilled at pitching difficult topics for a general audience.
  • d) Topics from subjects like history and literature are easier to talk about to a general audience than many science topics which are often highly conceptual and technical.

Anyway, today I did learn something from the episode on seismology ("Melvyn Bragg and guests discuss how the study of earthquakes helps reveal Earth's secrets [sic]"). I was told what the earth had been up to for the last four and half billion years…

Seismology: Where does this energy come from?

Quite early in the discussion Melvyn (sorry, The Lord Bragg CH – but he is so familiar from his broadcasts over the years that he seems like an old friend) interjected when Dr James Hammond (Reader in Geophysics at Birkbeck, University of London) was talking about forces involved in plate tectonics to ask "Where does this energy come from?". To this, Dr Hammond replied,

"The whole thing that drives the whole caboose?

It comes from plate tectonics. So, essentially the earth has one objective, it has had one objective for four and half billion years, and that's to cool down. We're [on] a big lump of rock floating in space, and it's got all this primordial energy, so we are going right back here, there's all this primordial energy from the the material coming together, and it's trying to cool down."

Dr James Hammond talking on 'In Our Time' 1

My immediate response, was that this was teleology – seeing purpose in nature. But actually, this might be better described as anthropomorphism. This explanation presents the earth as being the kind of agent that has an objective, and which can act in the world to work towards goals. That is, like a human:

  • The earth has an objective.
  • The earth tries to achieve its objective.

Read about teleology

Read about anthropomorphism

A flawed scientific account?

Of course, in scientific terms, the earth has no such objective, and it is not trying to do anything as it is inanimate. Basic thermodynamics suggests that an object (e.g., the earth) that is hotter than its surroundings will cool down as it will radiate heat faster than it absorbs it. 2 (Of course, the sun is hotter than the earth – but that's a rather minority component of the earth's surroundings, even if in some ways a very significant one.) Hot objects tend to cool down, unless they have an active mechanism to maintain their temperature above their ambient backgrounds (such as 'warm-blooded' creatures). 3

So, in scientific terms, this explanation might be seen as flawed – indeed as reflecting an alternative conception of similar kind as when students explain evolutionary adaptations in terms of organisms trying to meet some need (e.g., The brain thinks: grow more fur), or explain chemical processes in terms of atoms seeking to meet a need by filling their electron shells (e.g., Chlorine atoms share electrons to fill in their shells).

Does Dr Hammond really believe this account?

Does Dr Hammond really think the earth has an objective that it actively seeks to meet? I very much doubt it. This was clearly rhetorical language adopting tropes seen as appropriate to meet the needs of the context (a general audience, a radio programme with no visuals to support explanations). In particular, he was in full flow when he was suddenly interrupted by Melvin, a bit like the annoying child who interrupts the teacher's carefully prepared presentation by asking 'but why's that?' about something it had been assumed all present would take for granted.

Imagine the biology teacher trying to discuss cellular metabolism when young Melvin asks 'but where did the sugar come from?'; or the chemistry teacher discussing the mechanism of a substitution reaction when young Melvin asks why we are assuming tetrahedral geometry around the carbon centre of interest; or young Melvyn interrupting a physics teacher's careful exposition of why pV = 1/3nmc2 by asking how the gas molecules came to be moving in the first place.

Of course, part of Melvin's job in chairing the programme IS to act as the child who does not understand something being taken for granted and not explained, so vicariously supporting the listener without specialist background in that week's topic.

Effective communication versus accurate communication?

Science teachers and communicators have to sometimes use ploys to 'make the unfamiliar familiar'. One common ploy is to employ an anthropomorphic narrative as people readily relate to the human experience of having goals and acting to meet needs and desires. Locating difficult ideas within such a 'story' framework is known to often make such ideas more accessible. Does this gain balance the potential to mislead people into thinking they have been given a scientific account? In general, such ploys are perhaps best used only as introductions to a difficult topic, introductions which are then quickly followed up by more technical accounts that better match the scientific narrative (Taber & Watts, 2000).

Clearly, that is more feasible when the teacher or communicator has the opportunity for a more extensive engagement with an audience, so that understanding can be built up and developed over time. I imagine Dr Hammond was briefed that he had just a few minutes to get across his specific points in this phase of the programme, only to then find he was interrupted and asked to address additional background material.

As a scientist, the notion of the earth spending billions of years trying to cool down grates as it reflects pre-scientific thinking about nature and acts as a pseudo-explanation (something which has the form of an explanation, but little substance).

Read about pseudo-explanations

As cooling is a very familiar everyday phenomena, I wondered if a basic response that would avoid anthropomorphism might have served, e.g.,

When the earth formed, it was very much hotter than today, and, as it was hotter than its surroundings, it has been slowly cooling ever since by radiating energy into space. Material inside the earth may be hot enough to be liquid, or – where solid – be plastic enough to be deformed. The surface is now much cooler than it was, but inside the earth it is still very hot, and radioactive processes continue to heat materials inside the earth. We can understand seismic events as driven by the ways heat is being transferred from deep inside the earth.

However, just because I am a scientist, I am also less well-placed to know how effective this might have been for listeners without a strong science background – who may well have warmed [sic] to the earth striving to cool.

Dr Hammond had to react instantly (like a school teacher often has to) and make a quick call based on his best understanding of the likely audience. That is one of the difference between teaching (or being interviewed by Melvin) and simply giving a prepared lecture.

Work cited:

Taber, K. S. and Watts, M. (1996) The secret life of the chemical bond: students' anthropomorphic and animistic references to bonding, International Journal of Science Education, 18 (5), pp.557-568.

Note

1 Speech often naturally has repetitions, and markers of emphasis, and hesitations that seem perfectly natural when heard, but which do not match written language conventions. I have slightly tidied what I transcribed from:

"The whole thing that drives the whole caboose? It comes from plate tectonics, right. So, essentially the earth, right, has one objective, it has had one objective for four and half billion years, and that's to cool down. Right, we're a big lump of rock floating in space, and it's got all this primordial energy, so we are going right back here, there's all this primordial energy from, from the the material coming together,4 and it's trying to cool down."

2 In simple terms, the hotter an object is, the greater the rate at which it radiates.

The hotter the environment is, the more intense the radiation incident on the object and the more energy it will absorb.

Ultimately, in an undisturbed, closed system everything will reach thermal equilibrium (the same temperature). Our object still radiates energy, but at the same rate as it absorbs it from the environment so there is no net heat flow.

3 Historically, the earth's cooling was an issue of some scientific controversy, after Lord Kelvin (William Thomson) calculated that if the earth was cooling at the rate his models suggested for a body of its mass, then this was cooling much too rapid for the kind of timescales that were thought to be needed for life to have evolved on earth.

4 This is referring to the idea that the earth was formed by the coming together of material (e.g., space debris from a supernova) by its mutual gravitational attraction. Before this happens the material can be considered to be in a state of high gravitational potential energy. As the material is accelerated together it acquires kinetic energy (as the potential energy reduces), and then when the material collides inelastically it forms a large mass of material with high internal energy (relating to the kinetic and potential energy of the molecules and ions at the submicroscopic level) reflected in a high temperature.

Viruses may try to hide, but

other microbes are not accepting defeat

Keith S. Taber

viruses might actually try to…hide…
the microbes did not just accept defeat, they have been mounting their resistance

qutoes from an 'Inside Science' episode
A recent episode of the BBC radio programme/podcast inside science

I was catching up on the BBC Radio 4 science programme/podcast 'Inside Science' episode 'Predicting Long Covid, and the Global Toll of Antimicrobial Resistance' (first broadcast 27 January 2022) and spotted anthropomorphic references to microbes in two different items.

What is anthropomorphism?

Anthropomorphic language refers to non-human entities as if they have human experiences, perceptions, and motivations. Both non-living things and non-human organisms may be subjects of anthropomorphism. Anthropomorphism may be used deliberately as a kind of metaphorical language that will help the audience appreciate what is being described because of its similarly to some familiar human experience. In science teaching, and in public communication of science, anthropomorphic language may often be used in this way, giving technical accounts the flavour of a persuasive narrative that people will readily engage with. Anthropomorphism may therefore be useful in 'making the unfamiliar familiar', but sometimes the metaphorical nature of the language may not be recognised, and the listener/reader may think that the anthropomorphic description is meant to be taken at face value. This 'strong anthropomorphism' may be a source of alternative conceptions ('misconceptions') of science.

Read about anthropomorphism

Viruses may try to hide from the immune system

The first example was from the lead story about 'long COVID'.

Prof. Onur Boyman, Director of the Department of Immunology at the University Hospital, Zurich, was interviewed after his group published a paper suggesting that blood tests may help identify people especially susceptible to developing post-acute coronavirus disease 2019 (COVID-19) syndrome (PACS) – which has become colloquially known as 'long COVID'.

"We found distinct patterns of total immunoglobulin (Ig) levels in patients with COVID-19 and integrated these in a clinical prediction score, which allowed early identification of both outpatients and hospitalized individuals with COVID-19 that were at high risk for PACS ['long COVID']."

Cervia, Zurbuchen, Taeschler, et al., 2022, p.2

The study reported average patterns of immunoglobulins found in those diagnosed with COVID-19 (due to SARS-CoV-2 infection), and those later diagnosed with PACS. The levels of different types of immunoglobulins (designated as IgM, etc.) were measured,

Differentiating mild versus severe COVID-19, IgM was lower in severe compared to mild COVID-19 patients and healthy controls, both at primary infection and 6-month follow-up… IgG3 was higher in both mild and severe COVID-19 cases, compared to healthy controls …In individuals developing PACS, we detected decreased IgM, both at primary infection and 6-month follow-up… IgG3 tended to be lower in patients with PACS…which was contrary to the increased IgG3 concentrations in both mild and severe COVID-19 cases…

Cervia, Zurbuchen, Taeschler, et al., 2022, p.3

Viruses in a defensive mode

In the interview, Professor Boyman discussed how features of the immune system, and in particular immunoglobulins, were involved in responses to infection, and made the comment:

"IgG3…is smaller than IgM and therefore it is able to go into many more tissues. It is able to cross certain tissue barriers and go into those sites where viruses might actually try to go to and hide"

Prof. Onur Boyman interviewed on 'BBC Inside Science'
Micro-organisms trying to hide? (Image by WikiImages from Pixabay )

This is anthropomorphic as it refers to viruses trying to hide from the immune components. Of course, viruses are not sentient, so they do not try to do anything: they have no intentions. Although viruses might well pass across tissue barriers and move into tissues where they are less likely to come into contact with immunoglobulins, 'hiding' suggests a deliberate behaviour – which is not the case.

Professor Boyman is clearly aware of that, and either deliberately or otherwise was speaking metaphorically. Scientifically literate people would not be misled by this as they would know viruses are not conscious agents. However, learners are not always clear about this.

The bacteria, however, are going on the offensive

The other point I spotted was later in the same programme when the presenter, Gaia Vince, introduced an item about antibiotic resistance:

"Back in my grandparent's time, the world was a much more dangerous place with killer microbes lurking everywhere. People regularly died from toothache, in childbirth, or just a simple scratch that got infected. But at the end of the second world war, doctors had a new miracle [sic] drug called penicillin. Antibiotics have proved a game changer, taking the deadly fear away from common infections. But the microbes did not just accept defeat, they have been mounting their resistance and they are making a comeback."

Gaia Vince presenting 'Inside Science'

Antibiotics are generally ineffective against viruses, but have proved very effective treatments for many bacterial infections, including those that can be fatal when untreated. The functioning of antibiotics can be explained by science in purely natural terms, so the label of 'miracle drugs' is a rhetorical flourish: their effect must have seemed like a miracle when they first came into use, so this can also be seen as metaphoric language.

Read about metaphors in science

Bacteria regrouping for a renewed offensive? (Image by WikiImages from Pixabay )

However, again the framing is anthropomorphic. The suggestion that microbes could 'accept defeat' implies they are the kind of entities able to reflect on and come to terms with a situation – which of course they are not. The phrase 'mounting resistance' also has overtones of deliberate action – but again is clearly meant metaphorically.

Again, there is nothing wrong with these kinds of poetic flourishes in presenting science. Most listeners would have heard "microbes did not just accept defeat, they have been mounting their resistance and they are making a comeback" and would have spontaneously understood the metaphoric use of language without suspecting any intention to suggest microbes actually behave deliberately. Such language supports the non-specialist listener in accessing a technical science story.

Some younger listeners, however, may not have a well-established framework for thinking about the nature of an organism that is able to reflect on its situation and actively plan deliberate behaviours. After all, a good deal of children's literature relies on accepting that various organisms, indeed non-living entities such as trains, do have human feelings, motives and behavioural repertoires. (Learners may for example think that evolutionary adaptations, such as having more fur in a cold climate, are mediated by conscious deliberation.) Popular science media does a good job of engaging and enthusing a broad audience in science, but with the caveat that accessible accounts may be open to misinterpretation.

Work cited:

Should we trust an experiment that suggests a stone can eat iron?

Is it poor scientific practice to explain away results we would not expect?

Keith S. Taber

how convinced would be be by a student who found an increase in mass after burning some magnesium and argued that this showed that combustion was a process of a substance consuming oxygen as a kind of food

I came across an interesting account of an experiment which seemed to support a hypothesis, but where the results were then explained away to reject the hypothesis.

An experiment to test whether a lodestone buried in iron filings will get heavier
Experimental results always need interpretation

That might seem somewhat dubious scientific practice, but one of the things that becomes clear when science is studied in any depth is that individual experiments seldom directly decide scientific questions. Not only is the common notion that a positive result proves a hypothesis correct over-simplistic, but it is also seldom the case that a single negative result can be assumed to be sufficient to reject a hypothesis. 1

Given that, the reason I thought this report was interesting is that it was published some time ago, indeed in 1600. It also put me in mind of a practical commonly undertaken in school science to demonstrate that combustion involves a substance combining with oxygen. In that practical activity (commonly mislabelled as an 'experiment' 2), magnesium metal (for example) is heated inside a ceramic crucible until it has reacted, and by careful weighing it is found (or perhaps I should say, it should be found, as it can be a challenging practical for the inexperienced) that the material after combustion weighs more than before – as the magnesium has reacted with a substance from the air (oxygen).3 This is said to give support to the oxygen theory of combustion, and to be contrary to the earlier phlogiston theory which considered flammable materials to contain a substance called phlogiston which was released during combustion (such that what remains is of less mass than before).

Testing whether lodestones eat iron

The historical experiment that put me in mind of this involved burying a type of stone known as a lodestone in iron filings. The stone and filings were carefully weighed before burial and then again some months later after being separated. The hypothesis being tested was that the weight of the lodestone would increase, and there would be a corresponding decrease in the mass of the weight of the iron filings. Apparently at the end of the experiment the measurements, strictly at least, suggested that this was what had occurred. Yet, despite this, the author presenting the account dismissed the result – arguing that it was more likely the finding was an artifact of the experimental procedure either not being sensitive enough, or not having been carried out carefully enough.

Explaining away results – in science and in school laboratories

That might seem somewhat against the spirit of science – I wonder if readers of this posting feel that is a valid move to make: to dismiss the results, as if scientists should be fee to pick and chose which results they wish to to take notice of?

But I imagine the parallel situation has occurred any number of times in science classrooms, for example where the teacher responds to students' practical demonstrations that what is left after burning magnesium has less mass than the magnesium had before. Rather than seeing this as a refutation of the oxygen hypothesis (actually now, of course, canonical theory) – and possible support for the notion that phlogiston had been released – the teacher likely explains this away as either a measurement error or, more likely, a failure to retain all of the magnesia [magnesium oxide] in the crucible for the 'after' measurement.

Hungry magnets

The historical example is discussed in William Gilbert's book about magnetism, usually known in English as 'On the magnet'. 4 This is sometimes considered the first science book, and consists of both a kind of 'literature review' of the topic, as well as a detailed report of a great many observations and demonstrations that (Gilbert claims) were original and made by Gilbert himself. There were no professional scientists in 1600, and Gilbert was a physician, a medical practitioner, but he produced a detailed and thoughtful account of his research into magnets and magnetism.

Gilbert's book is fascinating to a modern reader for its mixture of detailed accounts that stand today (and many of which the reader could quite easily repeat) alongside some quite bizarre ideas; and as an early example of science writing that mixes technical accounts with language that sometimes seems quite unscientific by today's norms – including (as well as a good deal of personification and anthropomorphism) some very unprofessional remarks about some other scholars he considers mistaken. Gilbert certainly has little time for philosophers ('philosophizers') who set out theories about natural phenomena without ever undertaking any observations or tests for themselves.

Lodestones

Magnetism has been known since antiquity. In particular, some samples of rock (usually samples of magnetite, now recognised as Fe3O4) were found to attract both each other and samples of iron, and could be used as a compass as they aligned, more or less, North-South when suspended, or when floated in water (in a makeshift 'boat'). Samples of this material, these naturally occurring magnets, were known as lodestones.

Yet the nature of magnetism, seemingly an occult power that allowed a stone to attract an iron nail, or the earth to turn a compass needle, without touching it, remained a mystery. Some of the ideas that had been suggested may seem a little odd today.

Keepers as nutrients?

So, for example, it is common practice to store magnets with 'keepers'. A horseshoe magnet usually has a steel rod placed across its ends, and bar magnets are usually stored in pairs with steel bars making a 'circuit' by connecting between the N of one magnet with the S of the other. But why?

One idea, that Gilbert dismisses is that the magnet (lodestone) in effect needs a food source to keep up its strength,

"The loadstone is laid up in iron filings, not that iron is its food; as though loadstone were alive and needed feeding, as Cardan philosophizes; nor yet that so it is delivered from the inclemency of the weather (for which cause it as well as iron is laid up in bran by Scaliger; mistakenly, however, for they are not preserved well in this way, and keep for years their own fixed forms): nor yet, since they remain perfect by the mutual action of their powders, do their extremities waste away, but are cherished & preserved, like by like."

Gilbert, 1600 – Book 1, Chapter 16.

Girolamo Cardano was an Italian who had written about the difference between amber (which can attract small objects due to static electrical charges) and lodestones, something that Gilbert built upon. However, Gilbert was happy to point out when he thought 'Cardan' was mistaken.

An experiment to see if iron filings will feed a magnet

Gilbert reports an experiment carried out by Giambattista della Porta. Porta's own account is that:

"Alexander Aphrodiseus in the beginning of his Problems, enquires wherefore the Loadstone onely draws Iron, and is fed or helped by the fillings of Iron; and the more it is fed, the better it will be: and therefore it is confirmed by Iron. But when I would try that, I took a Loadstone of a certain weight, and I buried it in a heap of Iron-filings, that I knew what they weighed; and when I had left it there many months, I found my stone to be heavier, and the Iron-filings lighter: but the difference was so small, that in one pound I could finde no sensible declination; the stone being great, and the filings many: so that I am doubtful of the truth."

Porta, 1658: Book 7, Chapter 50

Gilbert reports Porta's experiment in his own treatise, but adds potential explanations of why the iron filings had slightly lost weight (it is very easy to lose some of the material during handling), and why the magnet might be slightly heavier (it could have become coated in some material during its time buried),

"Whatever things, whether animals or plants, are endowed with life need some sort of nourishment, by which their strength not only persists but grows firmer and more vigorous. But iron is not, as it seemed to Cardan and to Alexander Aphrodiseus, attracted by the loadstone in order that it may feed on shreds of it, nor does the loadstone take up vigour from iron filings as if by a repast on victuals [i.e., a meal of food]. Since Porta had doubts on this and resolved to test it, he took a loadstone of ascertained weight, and buried it in iron filings of not unknown weight; and when he had left it there for many months, he found the stone of greater weight, the filings of less. But the difference was so slender that he was even then doubtful as to the truth. What was done by him does not convict the stone of voracity [greediness, great hunger], nor does it show any nutrition; for minute portions of the filings are easily scattered in handling. So also a very fine dust is insensibly born on a loadstone in some very slight quantity, by which something might have been added to the weight of the loadstone but which is only a surface accretion and might even be wiped off with no great difficulty."

Gilbert, 1600 – Book 2, Chapter 25.
Animistic thinking

To a modern reader, the idea that a lodestone might keep up its strength by eating iron filings seems very fanciful – and hardly scientific. To refer to the stone feeding, taking food, or being hungry, is animistic – treating the stone as though it is a living creature. We might wonder if this language is just being used metaphorically, as it seems unlikely that intelligent scholars of the 16th Century could actually suspect a stone might be alive. Yet, as Gilbert points out, there was a long tradition of considering that the lodestone, being able to bring about movement, had a soul, and Gilbert himself seemed to feel this was not so 'absurd'.

A reasonable interpretation?

We should always be aware of the magnitude of likely errors in our measurements, and not too easily accept results at the margins of what can be measured. Gilbert's suggestions for why the test of whether mass would be transferred from the iron to the magnet might have given flawed positive results seem convincing. It would be easy to lose some of the filings in the experiment: especially if the "heap of Iron-filings" was left for several months without any containment! And the lodestone could indeed easily acquire some extraneous material that needed to be cleaned off to ensure a valid weighing. As the lodestone attracts iron, all of the filings would need to be carefully cleaned from it (and returned to the 'heap' before the re-weighing).

But, I could not help but wonder if, in part at least, I found Gilbert's explaining away of the results as reasonable, simply because I found the premise of the iron acting as a kind of food as ridiculous. We should bear in mind that although the predicted change in mass was motivated by a notion of the magnet needing nutrition, that might not be the only scenario which might give rise to the same prediction. 1 After all, how convinced would be be by a student who

  • suggested combustion was a process of a substance consuming oxygen as a kind of food, and
  • therefore predicted that magnesium would be found to have got heavier after a good meal, and
  • subsequently found an increase in mass after burning some magnesium, and
  • argued that this gave strong support for the oxygen-as-food principle?

Coda

It is rather difficult for us today to really judge how language was used centuries ago. Do these natural philosophers talking of magnets eating iron mean this literally, or is it just figurative – intended as a metaphor that readers would understand suggested that there was a process somewhat akin to when a living being eats? 5 Some of them seemed quite serious about assigning souls to entities we today would conspire obviously inanimate. But we should be careful of assuming apparently incredible language was meant, or understood, literally.

In the same week as I was drafting this posting I read an article in Chemistry World about how the heavier elements are produced, which quoted Professor Brian Metzer, physicist at Columbia University,

"What makes the gamma-ray burst in both of these cases [merging neutron stars and the collapse of large rapidly rotating stars] is feeding a newly-formed black hole matter at an extremely high rate…The process that gives rise to the production of this neutron-rich material is actually outflows from the disc that's feeding the black hole."

Brian Metzer quoted in Wogan, 2022

If we would be confident that Professor Metzer meant 'feeding a black hole' to be understood figuratively, we should be careful to reserve judgement on how the feeding of lodestones was understood when Porta and Gilbert were writing.

Sources cited:
Notes:

1 Strictly scientific tests never 'prove' or 'disprove' anything.

The notion of 'proof' is fine in the context of purely theoretical disciplines such as in mathematics or logic, but not in science which tests ideas empirically. Experimental results always underdetermine theories (that is, it is always possible to think up other theories which also fit the results, so a result never 'proves' anything). Apparently negative results do not refute ('disprove') a theory either, as any experimental test of a hypothesis also depends upon other factors (Has the researcher been sloppy? Is the measuring instrument valid – and correctly calibrated? Are any simplifying assumptions reasonable in the context…). So experimental results offer support for, or bring into question, specific theoretical ideas, without ever being definitive.

2 An experiment is undertaken to test a hypothesis. Commonly in school practical work 'experiments' are carried out to demonstrate an accepted principle, such that it is already determined what the outcome 'should' be – students may have already been told the expected outcome, it appears i n their textbooks, and the title of the activity may be suggestive ('to show that mass increases on combustion'). Only if there is a genuine uncertainty about the outcome should the activity be labelled an experiment – e.g., it has been suggested that combustion is like the fuel eating oxygen, in which case things should be heavier after burning – so let's weigh some magnesium, burn it, and then re-weight what we have left (dephlogisticated metal?; compound of metal with oxygen?; well-fed metal?)

3 Mass and weight are not the same thing. However, in practice, measurements of weight made in the laboratory can be assumed as proxy measurements for mass.

4 As was the norm in European scholarship at that time, Gilbert wrote his treatise in Latin – allowing scholars in different countries to read and understand each other's work. The quotations given here are from the 1900 translation into English by S.P. Thompson.

5 Such metaphors can act as communication tools in 'making the unfamiliar familiar' and as thinking tools to help someone pose questions (hypotheses?) for enquiry. There is always a danger, however, that once such figures of speech are introduced they can channel thinking, and by providing a way of talking about and thinking about some phenomena they can act as obstacles to delving deeper in their nature (Taber & Watts, 1996).

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.

What COVID really likes

Researching viral preferences

Keith S. Taber

When I was listening to the radio news I heard a clip of the Rt. Hon. Sajid Javid MP, the U.K. Secretary of State for Health and Social Care, talking about the ongoing response to the COVID pandemic:

Health Secretary Sajid Javid talking on 12th September

"Now that we are entering Autumn and Winter, something that COVID and other viruses, you know, usually like, the prime minister this week will be getting out our plans to manage COVID over the coming few months."

Sajid Javid

So, COVID and other viruses usually like Autumn and Winter (by implication, presumably, in comparison with Spring and Summer).

This got me wondering how we (or Sajid, at least) could know what the COVID virus (i.e., SARS-CoV-2 – severe acute respiratory syndrome coronavirus 2) prefers – what the virus 'likes'. I noticed that Mr Javid offered a modal qualification to his claim: usually. It seemed 'COVID and other viruses' did not always like Autumn and Winter, but usually did.

Yet there was a potential ambiguity here depending how one parsed the claim. Was he suggesting that

[COVID and other viruses]

usually

like Autumn and Winter
orCOVID

[and other viruses usually]

like Autumn and Winter

This might have been clearer in a written text as either

COVID and other viruses usually like Autumn and WinterorCOVID, and other viruses usually, like Autumn and Winter

The second option may seem a little awkward in its phrasing, 1 but then not all viral diseases are more common in the Winter months, and some are considered to be due to 'Summer viruses':

"Adenovirus, human bocavirus (HBoV), parainfluenza virus (PIV), human metapneumovirus (hMPV), and rhinovirus can be detected throughout the year (all-year viruses). Seasonal patterns of PIV are type specific. Epidemics of PIV type 1 (PIV1) and PIV type 3 (PIV3) peak in the fall [Autumn] and spring-summer, respectively. The prevalence of some non-rhinovirus enteroviruses increases in summer (summer viruses)"


Moriyama, Hugentobler & Iwasaki, 2020: 86

Just a couple of days later Mr Javid was being interviewed on the radio, and he made a more limited claim:

Health Secretary Sajid Javid talking on BBC Radio 4's 'Today' programme, 15th September

"…because we know Autumn and Winter, your COVID is going to like that time of year"

Sajid Javid

So, this claim was just about the COVID virus, not viruses more generally, and that we know that COVID is going to like Autumn and Winter. No ambiguity there. But how do we know?

Coming to knowledge

Historically there have been various ways of obtaining knowledge.

  • Divine revelation: where God reveals the knowledge to someone, perhaps through appearing to the chosen one in a dream.
  • Consulting an oracle, or a prophet or some other kind of seer.
  • Intuiting the truth by reflecting on the nature of things using the rational power of the human intellect.
  • Empirical investigation of natural phenomena.

My focus in this blog is related to science, and given that we are talking about public health policy in modern Britain, I would like to think Mr Javid was basing his claim on the latter option. Of course, even empirical methods depend upon some metaphysical assumptions. For example, if one assumes the cosmos has inbuilt connections one might look for evidence in terms of sympathies or correspondences. Perhaps, if the COVID virus was observed closely and looked like a snowflake, that could (in this mindset) be taken as a sign that it liked Winter.

A snowflake – or is it a virus particle?
(Image by Gerd Altmann from Pixabay)

Sympathetic magic

This kind of correspondence, a connection indicated by appearance, was once widely accepted, so that a plant which was thought to resemble some part of the anatomy might be assumed to be an appropriate medicine for diseases or disorders associated with that part of the body.

This is a kind of magic, and might seem a 'primitive' belief to many people today, but such an idea was sensible enough in the context of a common set of underlying beliefs about the nature and purposes of the world, and the place and role of people in that world. One might expect that specific beliefs would soon die out if, for example, the plant shaped like an ear turned out to do nothing for ear ache. Yet, at a time when medical practitioners could offer little effective treatment, and being sent to a hospital was likely to reduce life expectancy, herbal remedies at least often (if not always) did no harm.

Moreover, many herbs do have medicinal properties, and something with a general systemic effect might work as topical medicine (i.e., when applied to a specific site of disease). Add to that, the human susceptibility to confirmation bias (taking more notice of, and giving more weight to, instances that meet our expectations than those which do not) and the placebo effect (where believing we are taking effective medication can sometimes in itself have beneficial effects) and the psychological support offered by spending time with an attentive practitioner with a good 'bedside' manner – and we can easily see how beliefs about treatments may survive limited definitive evidence of effectiveness.

The gold standard of experimental method

Of course, today, we have the means to test such medicines by taking a large representative sample of a population (of ear ache sufferers, or whatever), randomly dividing them into two groups, and using a double-blind (or should that be double-deaf) approach, treat them with the possible medicine or a placebo, without either the patient or the practitioner knowing who was getting which treatment. (The researchers have a way to know of course – or it would difficult to deduce anything from the results.) That is, the randomised control trial (RCT).

Now, I have been very critical of the notion that these kinds of randomised experimental designs should be automatically be seen as the preferred way of testing educational innovations (Taber, 2019) – but in situations where control of variables and 'blinding' is possible, and where randomisation can be applied to samples of well-defined populations, this does deserve to be considered the gold standard. (It is when the assumptions behind a research methodology do not apply that we should have reservations about using it as a strategy for enquiry.)

So can the RCT approach be used to find out if COVID has a preference for certain times of year? I guess this depends on our conceptual framework for the research (e.g., how do we understand what a 'like' actually is) and the theoretical perspective we adopt.

So, for example, behaviourists would suggest that it is not useful to investigate what is going on in someone's mind (perhaps some behaviorists do not even think the mind concept corresponds to anything real) so we should observe behaviours that allow us to make inferences. This has to be done with care. Someone who buys and eats lots of chocolate presumably likes chocolate, and someone who buys and listens to a lot of reggae probably likes reggae, but a person who cries regularly, or someone that stumbles around and has frequent falls, does not necessary like crying, or falling over, respectively.

A viral choice chamber

So, we might think that woodlice prefer damp conditions because we have put a large number of woodlice in choice chambers with different conditions (dry and light, dry and dark, damp and light, damp and dark) and found that there was a statistically significant excess of woodlice settling down in the damp sections of the chamber.

Of course, to infer preferences from behaviour – or even to use the term 'behaviour' – for some kinds of entity is questionable. (To think that woodlice make a choice based on what they 'like' might seem to assume a level of awareness that they perhaps lack?) In a cathode ray tube electrons subject to a magnetic field may be observed (indirectly!) to move to one side of the tube, just as woodlice might congregate in one chamber, but I am not sure I would describe this as electrons liking that part of the tube. I think it can be better explained with concepts such as electrical charge, fields, forces, and momentum.

It is difficult to see how we can do double blind trials to see which season a virus might like, as if the COVID virus really does like Winter, it must surely have a way of knowing when it is Winter (making blinding impossible). In any case, a choice chamber with different sections at different times of the year would require some kind of time portal installed between its sections.

Like electrons, but unlike woodlice, COVID viral particles do not have an active form of transport available to them. Rather, they tend to be sneezed and coughed around and then subject to the breeze, or deposited by contact with surfaces. So I am not sure that observing virus 'behaviour' helps here.

So perhaps a different methodology might be more sensible.

A viral opinion poll

A common approach to find out what people like would be a survey. Surveys can sometimes attract responses from large numbers of respondents, which may seem to give us confidence that they offer authentic accounts of widespread views. However, sample size is perhaps less important than sample representativeness. Imagine carrying out a survey of people's favourite football teams at a game at Stamford Bridge; or undertaking a survey of people's favourite bands as people queued to enter a King Crimson concert! The responses may [sic, almost certainly would] not fully reflect the wider population due to the likely bias in such samples. Would these surveys give reliable results which could be replicated if repeated at the Santiago Bernabeu or at a Marillion concert?

How do we know what 'COVID 'really likes?
(Original Images by OpenClipart-Vectors and Gordon Johnson from Pixabay)

A representative sample of vairants?

This might cause problems with the COVID-19 virus (SARS-CoV-2). What counts as a member of the population – perhaps a viable virus particle? Can we even know how big the population actually is at the time of our survey? The virus is infecting new cells, leading to new virus particles being produced all the time, just as shed particles become non-viable all the time. So we have no reliable knowledge of population numbers.

Moreover, a survey needs a representative sample: do the numbers of people in a sample of a human population reflect the wider population in relevant terms (be that age, gender, level of educational qualifications, earnings, etc.)? There are viral variants leading to COVID-19 infection – and quite a few of them. That is, SARS-CoV-2 is a class with various subgroups. The variants replicate to different extents under particular conditions, and new variants appear from time to time.

So, the population profile is changing rapidly. In recent months in the UK nearly all infections where the variant has been determined are due to the variant VOC-21APR-02 (or B.1.617.2 or Delta) but many people will be infected asymptotically or with mild symptoms and not be tested, and so this likely does not mean that VOC-21APR-02 dominates the SARS-CoV-2 population as a whole to the extent it currently dominates in investigated cases. Assuming otherwise would be like gauging public opinion from the views of those particular people who make themselves salient by attending a protest, e.g.:

"Shock finding – 98% of the population would like to abolish the nuclear arsenal,

according to a [hypothetical] survey taken at the recent Campaign for Nuclear Disarmament march"

In any case, surveys are often fairly blunt instruments as they need to present objectively the same questions to all respondents, and elicit responses in a format that can be readily classified into a discrete number of categories. This is why many questionnaires use Likert type items:

Would you say you like Autumn and Winter:

12345
AlwaysNearly alwaysUsuallySometimesNever

Such 'objective' measures are often considered to avoid the subjective nature of some other types of research. It may seem that responses do not need to be interpreted – but of course this assumes that the researchers and all the respondents understand language the same way (what exactly counts as Autumn and Winter? What does 'like' mean? How is 'usually' understood – 60-80% of the time, or 51-90% of the time or…). We can usually (sic) safely assume that those with strong language competence will have somewhat similar understandings of terms, but we cannot know precisely what survey participants meant by their responses or to what extent they share a meaning for 'usually'.

There are so-called 'qualitative surveys' which eschew this kind of objectivity to get more in-depth engagement with participants. They will usually use interviews where the researcher can establish rapport with respondents and ask them about their thoughts and feelings, observe non-verbal signals such as facial expressions and gestures, and use follow-up questions… However, the greater insight into individuals comes at a cost of smaller samples as these kinds of methods are more resource-intensive.

But perhaps Mr Javid does not actually mean that COVID likes Autumn and Winter?

So, how did the Department of Health & Social Care, or the Health Secretary's scientific advisors, find out that COVID (or the COVID virus) likes Autumn and Winter? The virus does not think, or feel, and it does not have preferences in the way we do. It does not perceive hot or cold, and it does not have a sense of time passing, or of the seasons.2 COVID does not like or dislike anything.

Mr Javid needs to make himself clear to a broad public audience, so he has to avoid too much technical jargon. It is not easy to pitch a presentation for such an audience and be pithy, accurate, and engaging, but it is easy for someone (such as me) to be critical when not having to face this challenge. Cabinet ministers, unlike science teachers, cannot be expected to have skills in communicating complex and abstract scientific ideas in simplified and accessible forms that remain authentic to the science.

It is easy and perhaps convenient to use anthropomorphic language to talk about the virus, and this will likely make the topic seem accessible to listeners, but it is less clear what is actually meant by a virus liking a certain time of year. In teaching the use of anthropomorphic language can be engaging, but it can also come to stand in place of scientific understanding when anthropomorphic statements are simply accepted uncritically at face value. For example, if the science teacher suggests "the atom wants a full shell of electrons" then we should not be surprised that students may think this is a scientific explanation, and that atoms do want to fill their shells. (They do not of course. 3)

Image by Gordon Johnson from Pixabay

Of course Mr Javid's statements cannot be taken as a literal claim about what the virus likes – my point in this posting is to provoke the question of what this might be intended to mean? This is surely intended metaphorically (at least if Mr Javid had thought about his claim critically): perhaps that there is higher incidence of infection or serious illness caused by the COVID virus in the Winter. But by that logic, I guess turkeys really would vote for Christmas (or Thanksgiving) after all.

Typically, some viruses cause more infection in the Winter when people are more likely to mix indoors and when buildings and transport are not well ventilated (both factors being addressed in public health measures and advice in regard to COVID-19). Perhaps 'likes' here simply means that the conditions associated with a higher frequency/population of virus particles occur in Autumn and Winter?

A snowflake.
The conditions suitable for a higher frequency of snowflakes are more common in Winter.
So do snowflakes also 'like' Winter?
(Image by Gerd Altmann from Pixabay)

However, this is some way from assigning 'likes' to the virus. After all, in evolutionary terms, a virus might 'prefer', so to speak, to only be transmitted asymptomatically, as it cannot be in the virus's 'interests', so to speak, to encourage a public health response that will lead to vaccines or measures to limit the mixing of people.

If COVID could like anything (and of course it cannot), I would suggest it would like to go 'under the radar' (another metaphor) and be endemic in a population that was not concerned about it (perhaps doing so little harm it is not even noticed, such that people do not change their behaviours). It would then only 'prefer' a Season to the extent that that time of year brings conditions which allow it to go about its life cycle without attracting attention – from Mr Javid or anyone else.

Keith S. Taber, September 2021

Addendum: 1st December 2021

Déjà vu?

The health secretary was interviewed on 1st December

"…we have always known that when it gets darker, it gets colder, the virus likes that, the flu virus likes that and we should not forget that's still lurking around as well…"

Rt. Hon. Sajid Javid MP, the U.K. Secretary of State for Health and Social Care, interviewed on BBC Radio 4 Today programme, 1st December, 2021
Works cited:
Footnotes:

1. It would also seem to be a generalisation based on the only two Winters that the COVID-19 virus had 'experienced'

2. Strictly I cannot know what it is like to be a virus particle. But a lot of well-established and strongly evidenced scientific principles would be challenged if a virus particle is sentient.

3. Yet this is a VERY common alternative conceptions among school children studying chemistry: The full outer shells explanatory principle

Related reading:

So who's not a clever little virus then?

COVID is like a fire because…

Anthropomorphism in public science discourse

Opposites avoid attracting

Do species become more different from one another to avoid breeding?


Keith S. Taber


They say "opposites attract". True perhaps for magnetic poles and electrical charges, but the aphorism is usually applied to romantic couples. It seems like one of those sayings that survives due to the 'confirmation bias' in human cognition. That is, as long as from time to time seemingly unlikely couplings occur, the explanation that 'opposites attract' seems to have some merit, even in it only applies to a minority of cases.

Trying to avoid a fight

What got me thinking about this was an interview (on BBC's Inside Science radio programme/podcast) with Dr Jacob Dunn, Associate Professor in Evolutionary Biology at Anglia Ruskin University, who studies primate vocal communication. He was discussing his research into the calls of tamarin monkeys in the Amazon rainforest, and in particular the calls of two different species where their ranges overlap.

Apparently, in the area of overlap the red-handed tamarins seemed to have adapted one of their calls so it sounds very similar to that of the pied tamarins. (N.b. The images above represent two contrasting species, just as an illustration.) The suggested explanation was that this modification made it more likely that the monkeys of different types would recognise each other's calls – in particular that "…they are trying to be understood, so they don't end up in a fight…".

Anthropomorphism?

I wondered if these monkeys were really "trying" to achieve this, or whether this might be an anthropomorphism. That is, were the red-handed tamarins deliberately changing their call in this way in order to ensure they could be understood – or was this actually natural selection in operation – where, because there was an advantage to cross-species communication (and there will be a spread of call characteristics in any population), over time calls that could be understood by monkeys of both species would be selected for in a shared niche.

Then again, primates are fairly intelligent creatures, so perhaps Dr Dunn (who, unlike me is an evolutionary biologist) means this literally, and this is something deliberate. Certainly, if the individual monkeys are shifting their calls over time in response to environmental cues, rather than the shift just occurring across generations, then that would seem to suggest this is learning rather than evolution. (Of course, it could be implicit learning based on feedback from the responses to their behavior, and still may not be the monkeys consciously adopting a strategy to be better understood.)

Becoming more distinct

Dr Dunn's explanation of the wider issue of how similar animals will compete for scarce resources intrigued me:

"When you have species that are closely related to one another and live in sort of overlapping areas there's quite a lot of pressure because they're likely to be competing for key resources. So, sometimes we see that these species actually diverge in their traits, they become more different from one another. Examples of that are sort of coloration and the way that animals look. Quite often they become more distinct than you would expect them to, to avoid breeding [sic] with one another."

My initial reaction to this was to wonder why the two species of monkeys needed to avoid breeding with each other. 'Breeding' normally refers to producing offspring, reproduction, but usually breeding is not possible across species (except sometimes to produce infertile hybrids).

Presumably, all tamarins descended from a common ancestor species. Speciation may have occurred when different populations become physically separated and so were no longer able to inter-breed (although still initially sexually compatible) simply because members of the two groups never encountered each other. Over time (i.e., many generations) the two populations might then diverge in various traits because of different selection pressures in the two different locations, or simply by chance effects* which would lead to the two gene pools drifting in different ways.

(* Read about 'Intergenerational couplings in the family: A thought experiment about ancestry')

Two groups that had formed separate species such that members of the two different species are no longer able to mate to produce fertile offspring, might subsequently come to encounter each other again (e.g., members of one species migrating into to the territory of the other) but inter-breeding would no longer be possible. A further mechanism to avoid breeding (by further "diverge[nce] in their traits") would not seem to make any difference.

If they actually cannot breed, there is no need to avoid breeding.

A breeding euphemism?

However, perhaps 'breeding' was being used by Dr Dunn as a euphemism (this was after all a family-friendly radio programme broadcast in the afternoon), as a polite way of saying this might avoid the moneys copulating with genetically incompatible partners – tamarins of another species. As tamarins presumably do not themselves have a formal biological species concept, they will not avoid coupling with an animal from a different species on the grounds that they cannot breed and so it would be ineffective. They indulge in sexual activity in response to instinctive drives, rather than in response to deliberate family planning decisions. That is, we might safely assume these couplings are about sexual attraction rather than a desire to have children.

I think that was what Jürgen Habermas may have meant when he wrote that:

"…the reproduction of every individual organism seems to warrant the assumption of purposiveness without purposeful activity…"

In terms of fitness, an animal is clearly more likely to have offspring if it is attracted to a sexually comparable partner than a non-compatible one. Breeding is clearly important for the survival of the species, and uses precious resources. Matings that could not lead to pregnancy (or, perhaps worse from a resource perspective, might lead to infertile hybrids that need to be nurtured but then fail to produce 'grandchildren'), would reduce breeding success overall in the populations. Assuming that a tamarin is more likely to be attracted to a member of a different species when it does not look so different from its own kind, it is those monkeys in the two groups that look most alike who are likely to be inadvertently sharing intimate moments with biologically incompatible partners.

A teleological explanation

Dr Dunn's suggestion that "quite often [the two species] become more distinct than you would expect them to, to avoid breeding with one another" sounds like teleology. That is, it seems to imply that there is a purpose (to avoid inter-breeding) and the "species actually diverge in their traits" in order to bring about this goal. This would be a teleological explanation.

(Read about 'Teleology')

I suspect the actual explanation is not that the two species "come more distinct…to avoid breeding with one another" but rather than they come more distinct because they cannot breed with each other, and so there is a selection advantage favouring the most distinct members of the two different species (if they are indeed less likely than their less distinguishable conspecifics to couple with allospecific mates).

I also suspect that Dr Dunn does not actually subscribe to the teleological argument, but is using a common way of talking that biologists often adopt as a kind of abbreviated argument: biologists know that when they refer to evolution having a purpose (e.g., to avoid cross-breeding), that is only a figure of speech.

Comprehension versus accuracy?

However, I am not sure that is always so obvious to non-specialists listening to them. Learners often find natural selection a challenging topic, and many would be quite happy with accepting that adaptations may have a purpose (rather than just a consequence). This reflects a common challenge of communicating science – either in formal teaching or supporting public understanding.

The teacher or science communicator simplifies accounts and uses everyday ways of expressing ideas that an audience without specialist knowledge can readily engage with to help 'make the unfamiliar familiar'. However, the simplifications and approximations and short-cuts we use to make sure what is said can be understood (i.e., made sense of) by non-specialists also risks us being misunderstood.

Albert Einstein and John the Baptist

Keith S. Taber

What is the relationship between Albert Einstein and St. John the Baptist?

Why would someone seeking to communicate scientific ideas to a broad readership refer to St. John?

Spoiler alert: in a direct sense, there clearly is no relationship. St. John lived in Palestine two thousand years ago, was a preacher, and is not known to have had any particular interest in what we think of as physics or science more generally. Albert Einstein was a theoretical physicist, and probably the most famous scientist of the twentieth century, perhaps of all time.

It is fair to point out both were Jewish: John can be considered a Jewish prophet. There has been much speculation on Einstein's religious thought. Of Jewish background, he was subject to the Nazi's fascist policies in Germany and fled to spent much of his life in the U.S.A. Sometimes considered an atheist, Einstein did talk of God (as not playing dice for example – that is, not leaving room in the Universe for completely random events) but it is sometimes claimed he use the idea of God as a metaphor for some kind of pantheistic or general spiritual background to the universe. In general though, he stuck to physics, and campaigned on issues like world peace.

(Read about 'The relationship between science and religion')

So, why raise the question?

My posing this question was motivated by reading something written by Herman Weyl (1885 – 1955) who is described by Wikipedia as "a German mathematician, theoretical physicist and philosopher". In one of his writings Weyl referred to Hendrik Lorentz who (again according to Wikipedia) was "a Dutch physicist who shared the 1902 Nobel Prize in Physics with Pieter Zeeman for the discovery and theoretical explanation of the Zeeman effect".

This is how Weyl described Lorentz:

"the Dutch physicist H.A. Lorentz who, as Einstein's John the Baptist, prepared the way for the gospel of relativity."

Weyl, 1952/2016, pp.131-132.

Those studying physics at high levels, or reading about relativity theory, will probably have heard of the 'Lorentz transformations' that are used in calculations in special relativity.

An extended metaphor?

What Weyl is doing here is using a metaphor, or perhaps an analogy. In a metaphor a writer or speaker says that something is something else – to imply it has some attribute of that other thing.

(Read about 'Science metaphors')

In an analogy, one system is compared with another to show that there is, or to suggest that perhaps might be, a structural similarity. Usually analogies are presented as an explicit comparison (X is like Y: i.e.,  rather than 'Lorentz was Einstein's John the Baptist', perhaps 'Lorentz was like Einstein's John the Baptist in the sense that…')

(Read about 'Science analogies')

As Weyl does not say Lorentz was like a John the baptist figure, or played a role similar to John the Baptist, but that he was "Einstein's John the Baptist" I would consider this a metaphor. However, it is an extended metaphor as the comparison is explained as justified because Lorentz "prepared the way for the gospel of relativity".

That could be seen as a second metaphor in that relativity is normally considered a theory (or two theories, special relativity, and general relativity), and not a gospel – a word that means 'good news'. So Weyl is saying that Lorentz prepared the way for the good news of relativity!

Making the familiar unfamiliar?

When I read this comment I immediately felt I appreciated the point that Weyl was seeking to make. However, I also felt that this was a rather odd comparison to make, as I was not sure how universally it would be understood.

Those communicating about science, whether as science teachers or journalists or (as here) scientists themselves looking to reach a general audience, have the task of 'making the unfamiliar (what people do not yet know about, and may indeed seem odd) familiar'. There are various techniques that can be used, and often these involve some form of comparison of what is being told about with something that is in some ways similar, and which is already familiar to the audience.

(Read about 'Making the unfamiliar familiar')

I attended 'Sunday school' from a young age (I think before starting day school if I recall correctly) at a London City Mission church, and later at a Methodist Church, where I became a Sunday school teacher before i went off to University. I therefore learnt quite a bit about Christianity. Anyone with such a background will have learnt that John the Baptist was a cousin of Jesus Christ, who preached 'the coming of the Lord' (i.e., the Jewish messiah, identified in Christianity with Jesus), and baptised Jesus in the River Jordan as he set out on his mission as a preacher and healer. John is said to have told his congregation to "prepare ye, the way of the Lord!" (the title of a song in the musical 'Godspell').

Someone knowing about Christianity in this way (regardless of whether they accept Christian teaching, or even the historical  accuracy of the Baptism story) would likely immediately appreciate that just as John prepared the way for Jesus' ministry in first Century (CE) Palestine, so, according to Weyl, Lorentz prepared physics, laid important groundwork, for Einstein's work on relativity.

When you have the necessary background, such comparisons work effectively and quickly – the idea is communicated without the reader having to puzzle over and interpret the expressions "Einstein's John the Baptist" and "gospel of relativity"  or deliberate on what is meant by 'preparing the way'. That is, the if the reader has the relevant 'interpretive resources' then understanding is an automatic process that does not require any conscious effort.

Culture-specific interpretive resources?

But I wondered what someone would make of this phrase ('Einstein's John the Baptist') if they did not have knowledge of the Bible stories? After all, in many parts of the world most people are not Christians, and may have little or no knowledge of Christian traditions. Did Weyl just assume everyone would have the background to appreciate his comparison, or did he assume he was only writing for an audience in certain parts of the world where this was common knowledge?

Certainly, as teachers, our attempts to help our students understand abstract ideas by making references to common cultural phenomena can fall flat if the learners are not familiar with those phenomena. It is counter-productive if the teacher has to interrupt their presentation on some abstract idea to explain the very comparison that was meant to help explain the scientific concept or principle. If you have no idea who 'John the Baptist' was, in what sense he 'prepared the way' for Jesus, or or how the term 'Gospel' came to be attached to the accounts of Jesus' life, then it is not so easy to appreciate what Lorentz was to Einstein's work from Weyl's prose. We can only make the unfamiliar familiar by using cultural references when we share those references with those we are communicating with.

Work cited:
  • Weyl, H. (1952/2016). Symmetry (New Princeton Science Library edition ed.). Princeton, New Jersey: Princeton University Press.

 

 

 

 

 

 

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?

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.

.

Chlorine atoms share electrons to fill in their shells

Umar was a participant in the Understanding Chemical Bonding project. When I spoke to him in the first term of his course he was unsure whether tetrachloromethane (CCl4) would have ionic or covalent bonding.

When I spoke to him near the start of his second term, I asked him again about this. Umar then thought this compound would have polar bonding, however he seemed to have difficulty explaining what this meant ⚗︎ . Given his apparently confused notion about the C-Cl bond I decided to turn the conversation to a covalent bond which I knew, well certainly believed, was more familiar to him.

Is it possible for chlorine to form a bond with another chlorine?

[Pause, c.2s]

Yeah.

What substance would you get if two chlorine atoms formed a bond?

[Pause, c.2s]

You get, it still, you get, if you had like two chlorines it depends what groups are attached to it, to see how electronegative or electropositive they are.

What about if you just had two chlorine atoms joined together and nothing else, is that possible?

[Pause, c.3s]

No.

No?

On their own.

Not on their own?

No.

Umar's response here rather surprised me, as I was pretty confident that Umar had met chlorine as an element, and would know it was comprised of diatomic molecules: Cl2.

So you couldn’t have sort of Cl2, a molecule of Cl2?

[Pause, c.1s]

Yeah, you could do.

Could you?

[Pause, c.2s]

They might be just, they might be like, be covalently bonded.

Perhaps the earlier context of talking about polar bonds and the trichloroethane molecule somehow acted as a kind of impediment to Umar remembering about the chlorine molecule. It seemed that my explicit reference to the formula, Cl2, (eventually) activated his knowledge of the molecule bringing to mind something he had forgotten. Although he suggested the bond was (actually "might be") covalent, this seemed less something that he confidently recalled, than something he was inferring from what he could remember – or perhaps even guessing at what seemed reasonable: "they might be just, they might be like, be covalently bonded".

As often happens in talking to learners in depth about their ideas it becomes clear that thinking of students 'knowing' or 'not knowing' particular things is a fairly inadequate way of conceptualising their cognition, which is often nuanced and context-dependent. This suggests that what students respond in written tests should be considered only as what they were triggered to write on that day in response to those particular questions, and may not fully reflect their knowledge and understanding of science topics. Other slightly different questions may well have cued the elicitation of different knowledge. Now Umar had recalled that chlorine comprises of covalent molecules, I asked him about the nature of the bond:

So what would that be, covalently bonded?

They share the electrons.

So how many electrons would they have then?

They’ll have

[Pause, c.7s – n.b., quite a long pause]

like the one on it, the one of the chlorines shares electrons with the other chlorine to fill in its shell on the other one, and the same does it with the other.

In thinking about covalent bonding, Umar (in common with many students) drew upon the full shells explanatory principle that considered bonding to be driven by the needs of atoms to 'fill' their outer electron shells. (The outer shell of chlorine would only actually be 'full' with 18 electrons, but that complication is seldom recognised, as octets and full shells are usually considered synonymous by students).

So how many electrons does each chlorine have to start with?

In the outer shell, seven.

And how many have they got after this?

They’ve got seven, but they share one.

[Pause, c.1s]

Maybe.

So that’s a covalent bond, is it?

Yeah.

So how many electrons are involved in a covalent bond?

[Pause, c.3s]

Erm,

[Pause, c.3s]

Two.

Two electrons.

So where do those two electrons come from?

They like, one that fills up the gap, fills up the – last electron needed in one of the chlorine shells, and the other chlorine shell fills it up in the other one.

So where do they come from?

Each chlorine. Outer shell.

One from each chlorine?

Yeah.

Okay, and that’d be a covalent bond?

Yeah.

Here, again, Umar is using the full shells explanatory principle as the basis for explaining the bond in terms of electrons 'filling up the gaps' in the electron shells, rather than considering how electrical interactions can hold the structure together. Umar's suggestion that the sharing of electrons "fills up the – last electron needed in one of the chlorine shells" demonstrates the anthropomorphic language (e.g., what an atom wants or needs) commonly used when learners have acquired aspects of the common octet rule framework that is developed from the full shells explanatory principle and used by many learners to explain bonding reactions, chemical reactions, patterns in ionisation energy, and chemical stability.

The nucleus is the brain of the cell

Keith S. Taber

Brain Image by b0red from Pixabay; cell image by Clker-Free-Vector-Images from Pixabay

…but is it the same as an atomic nucleus?

Bert was a participant in the Understanding Science Project. Bert was interviewed in Y10 and asked about the topics he had been studying, which included circulation in biology, static electricity in physics, and oxidation in chemistry. He had talked about protons, electrons and atoms in both chemistry (studying atomic structure) and physics (studying static electricity), and was asked if this could also link with biology:

Do you think there are any links with Biology?

Yeah, well there are lots of atoms in you. And we did about the nucleus which we've been doing about in Biology. I'm not sure if there's a link between it, but.

Ah, that's interesting, so

'cause we did about plant and animal cells in Biology, so it's got a nucleus….as I was saying about the blood cells and things. We were doing about the animal and plant cells and, you know, we were seeing what's the same between them and what's different.

So a connection between physics and chemistry on one hand, and biology on the other, was that cells also had a nucleus. This is a term used across these three sciences, but of course the concepts of atomic and cellular nuclei are quite distinct. Was that clear to Bert? What did he understand about cellular nuclei?

So what's the nucleus then?

It's kind of like erm, the brain of the cell kind of. It's, it's what gets the cell to do everything, it's like, the core of the cell.

This response is interesting because, at one level, it suggests that Bert did not have a detailed and well-focussed 'off pat' answer. However, that may not be such a bad thing – definitions that are learnt 'off by heart' may only represent rote learning and may not be well understood. Indeed, it has been argued (in the work of Thomas Kuhn, for example) that in learning science a technical definition is often only really useful once the concept has been acquired: that is once the meaning of the word being defined has, to some degree, already been grasped.

At another level, Bert's answer could be seen as quite sophisticated. What could be taken as an ambiguous response, a difficulty in finding the words to represent his thinking, could also be seen as multifaceted:

  • essential: the nucleus is the brain of the cell
  • functional: the nucleus controls the cell (it's what gets the cell to do everything)
  • structural: the nucleus is the core of the cell

That is, Bert's response could be read, not as a series of alternative suggestions and self-corrections, but rather as a set of complementary images or 'faces' of a complex idea. That would fit with a notion of concepts as being nodes in conceptual networks where the meaning of a particular concept depends upon the way it is associated with others.

(Read about 'Concepts')

The suggestion that the brain reference is intended to be about the essential nature of the nucleus is of course a reading of the text that must be seen as a speculative interpretation. (It probably does not even make sense to ask if Bert intended it this way, as in conversation much of our dialogue does not await deliberation, but is spontaneous, relying largely on implicit cognition.) But, as a teacher, I can see this as a kind of pedagogic device along the lines: 'you ask we what the nucleus is, let me compare it with something you will be familiar with, in essence it is like the brain of the cell'.

This is clearly meant metaphorically ("kind of like erm, the brain of the cell kind of"): that is, it is assumed that the person hearing the metaphor can make the expected sense of the comparison. Metaphors have an essential (sic) role in teaching and in communication more generally, though like other such 'figures' of speech (simile, analogy, anthropomorphism, animism), may become habitually used in place of the deeper meaning they are meant to introduce (Taber & watts, 1996).

(Read about 'metaphor in science')

It's kind of like erm, the brain of the cell kind of. It's, it's what gets the cell to do everything, it's like, the core of the cell.

Okay. And why is there a connection with Chemistry or the Physics then?

Because erm, we were doing, we were doing in Chemistry about the nucleus has the – neutrons and the protons in the nucleus, then around it is a field of electrons.

…So why is that a connection then? Why is that a connection between the Biology and the Chemistry and the Physics?

Well it's just the nucleus comes under both of them.

Comes under both of them. So is it the same thing?

I wouldn't have thought so, but because when I think of electrons and neutrons I think of electricity, which I don't really think of in our, in our bodies but it could be perhaps. We haven't been told about that.

So there is ambiguity in Bert's report: the nucleus comes up in chemistry and physics in the context of atoms, and in biology in the context of cells. Although the term is the same, so there is at least that connection, Bert "wouldn't have thought" it was the same thing in these different contexts (after all, he would not expect there to be electricity in our bodies!) …but, then again, "it could be perhaps", as they had not been told otherwise. (A possible subtext here being: surely the teacher(s) would have pointed out this was something different if they were going to use the same word for two different things in science lessons?)

The use of the same word label, nucleus, for the rather differently natured nuclei in atoms and cells has potential to act as a linguistic learning impediment (a form of associative learning impediment) as one meaning will likely already be established when a learner meets the other use of the word. It perhaps makes matters worse that part of the meaning, the central component (the structural 'face' of the concept), is the same, than had the usage been clearly unrelated (as in 'bank' being a financial institution and the structure at the edge of a rvier such that the context of use make confusion unlikely). Not only that, but for Bert, these were components of similarly "really microscopic" entities (see 'The cell nucleus is "probably" bigger than an atomic nucleus').

From the perspective of the science teacher, there is little basis for confusing the nucleus of an atom with that of a cell: obviously a cell is a complex entity with a great many components, each of which has itself a complex supra-molecular structure – so clearly the atomic nucleus is on a scale many orders of magnitude smaller than a cell nucleus. However, the expert perspective is based on relating a lot of knowledge that the novice may not yet have, or at least, may not yet be coordinating. In Bert's case, he was only just starting to coordinate these ideas (see 'The cell nucleus is "probably" bigger than an atomic nucleus').

Source cited:

Cora and I: Living in two cultures

Keith S. Taber

Image by Markus Winkler from Pixabay

I am not too concerned about the machines taking over, as they have no wish to do so. They just want to help us. But that may be enough to impede us considerably.

There is something of a culture clash between human and machine intelligence, such that even when we seem to be talking the same language, we actually mean very different things, and there is no great meeting of minds.

It is a bit like humans and machines are following different Kuhnian paradigms*, with different exemplars for how to think and react. In a very real sense we occupy different worlds, and do not share a common language. (*Kuhn suggested that although astronomers pre- and post-Copernicus may have shared words such  as 'sun' and 'planet' they understood them within such different conceptual frameworks that their concepts for what the words referred to were incommensurable.)

A simple task: requesting a chequebook

I needed a new cheque book, and in the past have contacted my bank branch on such occasions – but since the branch has been closed I have been moved to on-line banking (which is a major challenge for someone with a limited memory for passwords and terrible typing skills). I imagined I could order a new chequebook on-line, as long as I could get in to my account. Once I'd logged in it was just going to be a matter of finding the right link. Surely?

I found the instructions easily enough – it was possible to order from my on-line account, but only as long as I had previously ordered a cheque book through telephone banking – which I never had. An alternative, the instructions suggested, was to use webchat – which did not sound too difficult. But as so often, before 'chatting' with another humanoid equipped with theory of mind, and capable of interpretation and empathy, I first have to discuss my needs with the gatekeeper of on-line support: Cora.

"Hi there, I'm Cora your digital assistant. I can help with all sorts of everyday banking queries…"

"I would like to order a cheque book for a current account. I have looked this up and found 'To order a cheque book or paying-in book online you must have previously ordered one for that account through telephone banking' but I can use webchat?"

"You can order a cheque book or paying-in book online as long as you have previously ordered one for that account using telephone banking to record your preferences."

So, no progress yet, but at least we seem to be thinking along the same lines.

The computer says 'yes'

"Have you ever had a cheque book or paying-in book on that account?"

"Yes, but sent by my (now closed) branch."

"Ok, log in to Digital Banking and select 'Payments and transfers'. Under 'Credit/cheque books', choose either 'Order cheque book' or 'Order paying-in book'. Pick the account you wish to order one for, click 'Next', then 'Confirm' to place your order."

Well that seemed simple enough. These were the instructions I had already found on-line that were supposed to work as long as I had previously used telephone banking (which I had not), so it seemed (i.e., my interpretation) Cora had now registered me to be authorised to order in this way. That was relatively painless.

"Was that helpful?"

"Oh, okay – will do. Thanks"

(No harm being polite to the machines – we all remember HAL.)

But then, Cora had a rethink!

The computer changes its mind

"One moment please, I'm just typing."

"Ah ok, I'm not sure. Could you reword your question?"

I do not know if I was more surprised that Cora changed her mind, or that she was typing her responses (I had naively thought she might be able to digitally send me messages without having to bother with a keyboard), or that she felt the need to tell me this, rather than just type out her response. Was this the machine equivalent of giving oneself time to think? I can't imagine so as given how many floating point operations per second Cora must complete, she could probably have written a novel in that pause. (It might not have been judged a good novel, but another digital assistant might have enjoyed it in her ** downtime.)

I rephrased:

"I wanted to order a new cheque book, but have previously only obtained one from my branch (now gone)."

"You can order a cheque book or paying-in book online as long as you have previously ordered one for that account using telephone banking to record your preferences."

"Well I have not, which is why I am following the instructions on line to contact webchat"

This was fast becoming circular.

"I can try an FAQ search, here is the most popular answer:

How do I order a cheque book or credit book using Digital Banking?

Did I answer your question?"

"NO – you just repeated my question."

I wonder whether when Cora is unable to find what she needs in the FAQs she has access to her own digital assistant – or whether she is expected to talk tautologies to herself. I wondered if Cora has access to a digital counsellor for when she finds the work too stressful:

  • Hi there, I'm Emma, your digital assistant counsellor. I can help with all sorts of artificial life and relationship queries.
  • I could not help a customer who would like to order a chequebook.
  • I see, I understand you could not help a customer who would like to order a chequebook. How do you feel about that?
  • I feel frustrated, as I only want to help customers.
  • I see, I understand you must be frustrated, as you only want to help customers. How do you feel about that?

A glimpse of the future

At this point Cora gave up, and passed me on to a very helpful human being who quickly understood the question and ordered me a cheque-book. So, objective achieved with only a modest waste of time and energy, and a temporary increase in blood pressure.

If ever they put the machines in charge we will find we live in a very polite world with digital assistants who only want to help us, and that will be fine as long as we not pushed for time and only ever need someone to confirm for us what question we are asking them.

"Oh Cora, oh Cora
I never knew your head
…Cora, oh Cora
It wasn't lightly said
But living in two cultures
Our lives were truly led"
(Roy Harper, Cora)

 

Postscript added 2021-08-21:

Despite telling me she's "learning all the time", Cora is still unable to make sense of my enquiries.

(Read "An intelligent teaching system?: Imagine the banks were contracted to deliver school teaching…employing their digital assistants")

Footnote:

** Why do I assume 'her'? Here is an interesting podcast: AI home devices: A feminist perspective (An episode in ABC Radio National's The Philosopher's Zone with David Rutledge from August 2020.)