What can either wander door to door, or rush to respond; and when it arrives might touch, sniff, nip, rear up, stroke, seal, or kill?
Keith S. Taber
a science teacher would need to be more circumspect in throwing some of these metaphors out there, without then doing some work to transition from them to more technical, literal, and canonical accounts
BBC Radio 4's 'Start the week' programme is not a science programme, but tends to invite in guests (often authors of some kind) each week according to some common theme. This week there was a science theme and the episode was titled 'Building the Body, Opening the Heart', and was fascinating. It also offers something of a case study in how science gets communicated in the media.
Sian Harding is Professor of Cardiac Pharmacology at the National Heart and Lung Institute, Imperial College London, and Director of the Imperial Cardiac Regenerative Medicine Centre
As a science educator I listen to science programmes both to enhance and update my own science knowledge and understanding, but also to hear how experts present scientific ideas when communicating to a general audience. Although neither science popularisation nor the work of scientists in communicating to the public is entirely the same as formal teaching (for example,
there is no curriculum with specified target knowledge; and
the audiences
are not well-defined,
are usually much more diverse than found in classrooms, and
are free to leave at any point they lose interest or get a better offer),
they are, like teachers, seeking to inform and explain science.
Science communicators, whether professional journalists or scientists popularising their work, face similar challenges to science teachers in getting across often complex and abstract ideas; and, like them, need to make the unfamiliar familiar. Science teachers are taught about how they need to connect new material with the learners' prior knowledge and experiences if it is to make sense to the students. But successful broadcasters and popularisers also know they need to do this, using such tactics as simplification, modelling, metaphor and simile, analogy, teleology, anthropomorphism and narrative.
Perhaps one of the the biggest differences between science teaching and science communication in the media is the ultimate criterion of success. For science teachers this is (sadly) usually, primarily at least, whether students have understood the material, and will later recall it, sufficiently to demonstrate target knowledge in exams. The teacher may prefer to focus on whether students enjoy science, or develop good attitudes to science, or will consider working in science: but, even so, they are usually held to account for students' performance levels in high-stakes tests.
Science journalists and popularisers do not need to worry about that. Rather, they have to be sufficiently engaging for the audience to feel they are learning something of interest and understanding it. Of course, teachers certainly need to be engaging as well, but they cannot compromise what is taught, and how it is understood, in order to entertain.
With that in mind, I was fascinated at the range of ways the panel of guests communicated the science in this radio show. Much of the programme had a focus on cells – and these were described in a variety of ways.
Talking about cells
Dr Rutherford introduced cells as
"the basic building blocks of life on earth"; and observed that he had
"spent much of my life staring down microscopes at these funny, sort of mundane, unremarkable, gloopy balloons"; before suggesting that cells were
"actually really these incredible cities buzzing with activity".
Dr. Mukherjee noted that
"they're fantastical living machines" [where a cell is the] "smallest unit of life…and these units were built, as it were, part upon part like you would build a Lego kit"
Listeners were told how Robert Hooke named 'cells' after observing cork under the microscope because the material looked like a series of small rooms (like the cells where monks slept in monasteries). Hooke (1665) reported,
"I took a good clear piece of Cork, and with a Pen-knife sharpen'd as keen as a Razor, I cut a piece of it off, and…cut off from the former smooth surface an exceeding thin piece of it, and…I could exceeding plainly perceive it to be all perforated and porous, much like a Honey-comb, but that the pores of it were not regular; yet it was not unlike a Honey-comb in these particulars
…these pores, or cells, were not very deep, but consisted of a great many little Boxes, separated out of one continued long pore, by certain Diaphragms, as is visible by the Figure B, which represents a sight of those pores split the long-ways.
Robert Hooke
Hooke's drawing of the 'pores' or 'cells' in cork
Components of cells
Dr. Mukherjee described how
"In my book I sort of board the cell as though it's a spacecraft, you will see that it's in fact organised into rooms and there are byways and channels and of course all of these organelles which allow it to work."
We were told that "the cell has its own skeleton", and that the organelles included the mitochondria and nuclei ,
"[mitochondria] are the energy producing organelles, they make energy in most cells, our cells for instance, in human cells. In human cells there's a nucleus, which stores DNA, which is where all the genetic information is stored."
A cell that secretes antibodies which are like harpoons or missiles that it sends out to kill a pathogen?
(Images by by envandrare and OpenClipart-Vectors from Pixabay)
Immune cells
Rutherford moved the conversation onto the immune system, prompting 'Sid' that "There's a lovely phrase you use to describe T cells, which is door to door wanderers that can detect even the whiff of an invader". Dr. Mukherjee distinguished between the cells of the innate immune system,
"Those are usually the first responder cells. In humans they would be macrophages, and neutrophils and monocytes among them. These cells usually rush to the site of an injury, or an infection, and they try to kill the pathogen, or seal up the pathogen…"
and the cells of the adaptive system, such as B cells and T cells,
"The B cell is a cell that eventually becomes a plasma cell which secretes antibodies. Antibodies, they are like harpoons or missiles which the cell sends out to kill a pathogen…
[A T cell] goes around sniffing other cells, basically touching them and trying to find out whether they have been altered in some way, particularly if they are carrying inside them a virus or any other kind of pathogen, and if it finds this pathogen or a virus in your body, it is going to go and kill that virus or pathogen"
A cell that goes around sniffing other cells, touching them? 1 (Images by allinonemovie and OpenClipart-Vectors from Pixabay)
Cells of the heart
Another topic was the work of Professor Harding on the heart. She informed listeners that heart cells did not get replaced very quickly, so that typically when a person dies half of their heart cells had been there since birth! (That was something I had not realised. It is believed that this is related to how heart cells need to pulse in synchrony so that the whole organ functions as an effective pumping device – making long lasting cells that seldom need replacing more important than in many other tissues.)
At least, this relates to the cardiomyocytes – the cells that pulse when the heart beats (a pulse that can now be observed in single cells in vitro). Professor Harding described how in the heart tissue there are also other 'supporting' cells, such as "resident macrophages" (immune cells) as well as other cells moving around the cardiomyocytes. She describe her observations of the cells in Petri dishes,
"When you look at them in the dish it's incredible to see them interact. I've got a… video [of] cardiomyocytes in a dish. The cardiomyocytes pretty much just stay there and beat and don't do anything very much, and I had this on time lapse, and you could see cells moving around them. And so, in one case, the cell (I think it was a fibroblast, it looked like a fibroblast), it came and it palpated at the cardiomyocyte, and it nipped off bits of it, it sampled bits of the cardiomyocyte, and it just stroked it all the way round, and then it was, it seemed to like it a lot.
[In] another dish I had the same sort of cardiomyocyte, a very similar cell came in, it went up to the cardiomyocyte, it touched it, and as soon as it touched it, I can only describe it as it reared up and it had, little blobs appeared all over its surface, and it rushed off, literally rushed off, although it was time lapse so it was two minutes over 24 hours, so, it literally rushed off, so what had it found, why did one like it and the other one didn't?"
Making the unfamiliar, familiar
The snippets from the broadcast that I have reported above demonstrate a wide range of ways that the unfamiliar is made familiar by describing it in terms that a listener can relate to through their existing prior knowledge and experience. In these various examples the listener is left to carry across from the analogue features of the familiar (the city, the Lego bricks, human interactions, etc.) those that parallel features of the target concept – the cell. So, for example, the listener is assumed to appreciate that cells, unlike Lego bricks, are not built up through rigid, raised lumps that fit precisely in depressions on the next brick/cell. 2
Analogies with the familiar
Hooke's original label of the cell was based on a kind of analogy – an attempt to compare what we has seeing with something familiar: "pores, or cells…a great many little Boxes". He used the familiar simile of the honeycomb (something directly familiar to many more people in the seventeenth century when food was not subject to large-scale industrialised processing and packaging).
Other analogies, metaphors and similes abound. Cells are visually like "gloopy balloons", but functionally are "building blocks" (strictly a metaphor, albeit one that is used so often it has become treated as though a literal description) which can be conceptualised as being put together "like you would build a Lego kit" (a simile) although they are neither fixed, discrete blocks of a single material, nor organised by some external builder. They can be considered conceptually as the"smallest unit of life"(though philosophers argue about such descriptions and what counts as an individual in living systems).
The machine description ("fantastical living machines") reflects one metaphor very common in early modern science and cells as "incredible cities" is also a metaphor. Whether cells are literally machines is a matter of how we extend or limit our definition of machines: cells are certainly not actually cities, however, and calling them such is a way of drawing attention to the level of activity within each (often, apparently from observation, quite static) cell. B cells secrete antibodies, which the listener is old are like (a simile) harpoons or missiles – weapons.
Skeletons of the dead
Whether "the cell has its own skeleton" is a literal or metaphorical statement is arguable. It surely would have originally been a metaphoric description – there are structures in the cell which can be considered analogous to the skeleton of an organism. If such a metaphor is used widely enough, in time the term's scope expands to include its new use – and it becomes (what is called, metaphorically) a 'dead metaphor'.
Telling stories about cells
A narrative is used to help a listener imagine the cell at the scale of "a spacecraft". This is "organised into rooms and there are byways and channels" offering an analogy for the complex internal structure of a cell. Most people have never actually boarded a spacecraft, but they are ubiquitous in television and movie fiction, so a listener can certainly imagine what this might be like.
Endoplastic reticulum? (Still from Star Trek: The Motion Picture, Paramount Pictures, 1979)
Oversimplification?
The discussion of organelles illustrates how simplifications have to be made when introducing complex material. This always brings with it dangers of oversimplification that may impede further learning, or even encourage the development of alternative conceptions. So, the nucleus does not, strictly, 'store' "all the genetic information" in a cell (mitochondria carry their own genes for example).
More seriously, perhaps, mitochondria do not "make energy". 'More seriously' as the principle of conservation of energy is one of the most basic tenets of modern science and is considered a very strong candidate for a universal law. Children are often taught in school that energy cannot be created or destroyed. Science communication which is contrary to this basic curriculum science could confuse learners – or indeed members of the public seeking to understand debates about energy policy and sustainability.
Anthropomorphising cells
Cells are not only compared to inanimate entities like balloons, building bricks, cities and spaceships. They are also described in ways that make them seem like sentient agents – agents that have experiences, and conscious intentions, just as people do. So, some immune cells are metaphorical 'first responders' and just as emergency services workers they "rush to the site" of an incident. To rush is not just to move quickly, buy to deliberately do so. (By contrast, Paul McAuley refers to "innocent" amoeboid cells that collectively form into the plasmodium of a slime mould spending most of their lives"bumbling around by themselves" before they "get together". ) The immune cells act deliberately – they "try" to kill. Other immune cells "send out" metaphorical 'missiles' "to kill a pathogen". Again this language suggests deliberate action (i.e., to send out) and purpose.
That is, what is described is not just some evolved process, but something teleological: there is a purpose to sending out antibodies – it is a deliberate act with an aim in mind. This type of language is very common in biology – even referring to the 'function' of the heart or kidney or a reflex arc could be considered as misinterpreting the outcome of evolutionary developments. (The heart pumps blood through the vascular system, but referring to a function could suggest some sense of deliberate design.)
Not all cells are equal
I wonder how many readers noticed the reference above to 'supporting' cells in the heart. Professor Harding had said
"When you look inside the [heart] tissue there are many other cells [than cardiomyocytes] that are in there, supporting it, there are resident macrophages, I think we still don't know really what they are doing in there"
Why should some heart cells be seen as more important and others less so? Presumably because 'the function' of a heart is to beat, to pump, so clearly the cells that pulse are the stars, and the other cells that may be necessary but are not obviously pulsing just a supporting cast. (So, cardiomyocytes are considered heart cells, but macrophages in the same tissue are only cells that are found in the heart, "residents" – to use an analogy of my own, like migrants that have not been offered citizenship!)3
That is, there is a danger here that this way of thinking could bias research foci leading researchers to ignore something that may ultimately prove important. This is not fanciful, as it has happened before, in the case of the brain:
"Glial cells, consisting of microglia, astrocytes, and oligodendrocyte lineage cells as their major components, constitute a large fraction of the mammalian brain. Originally considered as purely non-functional glue for neurons, decades of research have highlighted the importance as well as further functions of glial cells."
Jäkel and Dimou, 2017
The lives of cells
Narrative is used again in relation to the immune cells: an infection is presented as a kind of emergency event which is addressed by special (human like) workers who protect the body by repelling or neutralising invaders. "Sniffing" is surely an anthropomorphic metaphor, as cells do not actually sniff (they may detect diffusing substances, but do not actively inhale them). Even "touching" is surely an anthropomorphism. When we say two objects are 'touching' we mean they are in contact, as we touch things by contact. But touching is sensing, not simply adjacency.
If that seems to be stretching my argument too far, to refer to immune cells "trying to find out…" is to use language suggesting an epistemic agent that can not only behave deliberately, but which is able to acquire knowledge. A cell can only "find" an infectious agent if it is (i.e., deliberately) looking for something. These metaphors are very effective in building up a narrative for the listener. Such a narrative adopts familiar 'schemata', recognisable patterns – the listener is aware of emergency workers speeding to the scene of an incident and trying to put out a fire or seeking to diagnose a medical issue. By fitting new information into a pattern that is familiar to the audience, technical and abstract ideas are not only made easier to understand, but more likely to be recalled later.
Again, an anthropomorphic narrative is used to describe interactions between heart cells. So, a fibroblast that "palpates at" a cardiomyocyte seems to be displaying deliberate behaviour: if "nipping" might be heard as some kind of automatic action – "sampling" and "stroking" surely seem to be deliberate behaviour. A cell that "came in, it went up [to another]" seems to be acting deliberately. "Rearing up" certainly brings to mind a sentient being, like a dog or a horse. Did the cell actually 'rear up'? It clearly gave that impression to Professor Harding – that was the best way, indeed the "only" way, she had to communicate what she saw.
Again we have cells "rushing" around. Or do we? The cell that had reared up, "rushed off". Actually, it appeared to "rush" when the highly magnified footage was played at 720 times the speed of the actual events. Despite acknowledging this extreme acceleration of the activity, the impression was so strong that Professor Harding felt justified in claiming the cell "literally rushed off, although it was time lapse so it was two minutes over 24 hours, so, it literally rushed off…". Whatever it did, that looked like rushing with the distortion of time-lapse viewing, it certainly did not literally rush anywhere.
But the narrative helps motivate a very interesting question, which is why the two superficially similar cells 'behaved' ('reacted', 'responded' – it is actually difficult to find completely neutral language) so differently when in contact with a cardiomyocyte. In more anthropomorphic terms: what had these cells "found, why did one like it and the other one didn't?"
Literally speaking?
Metaphorical language is ubiquitous as we have to build all our abstract ideas (and science has plenty of those) in terms of what we can experience and make sense of. This is an iterative process. We start with what is immediately available in experience, extend metaphorically to form new concepts, and in time, once those have "settled in" and "taken root" and "firmed up" (so to speak!) they can then be themselves borrowed as the foundation for new concepts. This is true both in how the individual learns (according to constructivism) and how humanity has developed culture and extended language.
So, should science communicators (whether scientists themselves, journalists or teachers) try to limit themselves to literal language?
Even if this were possible, it would put aside some of our strongest tools for 'making the unfamiliar familiar' (to broadcast audiences, to the public, to learners in formal education). However these devices also bring risks that the initial presentations (with their simplifications and metaphors and analogies and anthropomorphic narratives…) not only engage listeners but can also come to be understood as the scientific account. That is is not an imagined risk is shown by the vast numbers of learners who think atoms want to fill their shells with octets of electrons, and so act accordingly – and think this because they believe it is what they have been taught.
Does it matter if listeners think the simplification, the analogy, the metaphor, the humanising story,… is the scientific account? Perhaps usually not in the case of the audience listening to a radio show or watching a documentary out of interest.
In education it does matter, as often learners are often expected to progress beyond these introductory accounts in their thinking, and teachers' models and metaphors and stories are only meant as a starting point in building up a formal understanding. The teacher has to first establish some kind of anchor point in the students' existing understandings and experiences, but then mould this towards the target knowledge set out in the curriculum (which is often a simplified account of canonical knowledge) before the metaphor or image or story becomes firmed-up in the learners' minds as 'the' scientific account.
'Building the Body, Opening the Heart' was a good listen, and a very informative and entertaining episode that covered a lot of ideas. It certainly included some good comparisons that science teachers might borrow. But I think in a formal educational context a science teacher would need to be more circumspect in throwing some of these metaphors out there, without then doing some work to transition from them to more technical, literal, and canonical accounts.
Jäkel S and Dimou L (2017) Glial Cells and Their Function in the Adult Brain: A Journey through the History of Their Ablation. Frontiers in Cellullar Neuroscience, 11:24. doi: 10.3389/fncel.2017.00024
1 The right hand image portrays a mine, a weapon that is used at sea to damage and destroy (surface or submarine) boats. The mine is also triggered by contact ('touch').
2 That is, in an analogy there are positive and negative aspects: there are ways in which the analogue IS like the target, and ways in which the analogue is NOT like the target. Using an analogy in communication relies on the right features being mapped from the familiar analogue to the unfamiliar target being introduced. In teaching it is important to be explicit about this, or inappropriate transfers may be made: e.g., the atom is a tiny solar system so it is held together by gravity (Taber, 2013).
3 It may be a pure coincidence in relation to the choice of term 'resident' here, but in medicine 'residents' have not yet fully qualified as specialist physicians or surgeons, and so are on placement and/or under supervision, rather than having permanent status in a hospital faculty.
One of the recurring themes in this blog is the way science is communicated in teaching and through media, and in particular the role of language choices, in effective communication.
I was listening to a podcast of the BBC Science in Action programme episode 'Radioactive Red Forest'. The item that especially attracted my attention (no, not the one about teaching fish to do sums) was summarised on the website as:
"Understanding the human genome has reached a new milestone, with a new analysis that digs deep into areas previously dismissed as 'junk DNA' but which may actually play a key role in diseases such as cancer and a range of developmental conditions. Karen Miga from the University of California, Santa Cruz is one of the leaders of the collaboration behind the new findings."
Website description of an item on 'Science in Action'
They've really sequenced the human genome this time
The introductory part of this item is transcribed below.
Being 'once a science teacher, always a science teacher' (in mentality, at least), I reflected on how this dialogue is communicating important ideas to listeners. Before I comment in any detail, you may (and this is entirely optional, of course) wish to read through and consider:
What does a listener (reader) need to know to understand the intended meanings in this text?
What 'tactics', such as the use of figures of speech, do the speakers use to support the communication process?
Roland Pease (Presenter): "Good news! They sequenced, fully sequenced, the human genome.
'Hang on a minute' you cry, you told us that in 2000, and 2003, and didn't I hear something similar in 2013?' Well, yes, yes, and yes, but no.
A single chromosome stretched out like a thread of DNA could be 6 or 8 cm long. Crammed with three hundred million [300 000 000] genetic letters. But to fit one inside a human cell, alongside forty five [45] others for the complete set, they each have to be wound up into extremely tight balls. And some of the resulting knots it turns out are pretty hard to untangle in the lab. and the genetic patterns there are often hard to decode as well. Which is what collaboration co-leader Karen Miga had to explain to me, when I also said 'hang on a minute'."
Karen Miga: "The celebrated release of the finished genome back in 2003 was really focused on the portions that we could at the time map and assemble. But there were big persistent gaps. Roughly about two hundred million [200 000 000] bases long that were missing. It was roughly eight percent [8%] of the genome was missing."
"And these were sort of hard to get at bits of genome, I mean are they like trying to find a coin in the bottom of your pocket that you can't quite pull out?"
"These regions are quite special, we think about tandem repeats or pieces of sequences that are found in a head-to-tail orientation in the genome, these are corners of our genome where this is just on steroids, where we see a tremendous amount of tandem repeats sometimes extending for ten million [10 000 000] bases. They are just hard to sequence, and they are hard to put together correctly and that was – that was the wall that the original human genome project faced."
Introduction to the item on the sequencing of what was known as 'junk DNA' in the (a) human genome
I have sketched out a kind of 'concept map' of this short extract of dialogue:
A mapping of the explicit connections in the extract of dialogue (ignoring connections and synonyms that a knowledgeable listener would have available for making sense of the talk)
In educational settings, teachers' presentations are informed by background information about the students' current levels of knowledge. In particular, teachers need to be aware of the 'prerequisite knowledge' necessary for understanding their presentations. If you want to be understood, then it is important your listeners have available the ideas you will be relying on in your account.
A scientist speaking to the public, or a journalist with a public audience, will be disadvantaged in two ways compared to the situation of a teacher. The teacher usually knows about the class, and the class is usually not as diverse as a public audience. There might be a considerable diversity of knowledge and understanding among the members of, say, the 13-14 year old learners in one school class, or the first year undergraduates on a university course – but how much more variety is found in the readership of a popular science magazine or the audience of a television documentary or radio broadcast.
Here are some key concepts referenced in the brief extract above:
bases
cells
chromosome
DNA
sequencing
tandem repeats
the human genome
To follow the narrative, one needs to appreciate relationships among these concepts (perhaps at least that chromosomes are found in cells; and comprised of DNA, the structure of which includes a number of different components called bases, the ordering of which can be sequenced to characterise the particular 'version' of DNA that comprises a genome. 1 ) Not all of these ideas are made absolutely explicit in the extract.
The notion of tandem repeats requires somewhat more in-depth knowledge, and so perhaps the alternative offered – tandem repeats or pieces of sequences that are found in a head to tail orientation in the genome – is intended to introduce this concept for those who are not familiar with the topic in this depth.
The complete set?
The reference to "A single chromosome stretched out…could be 6 or 8 cm long…to fit one inside a human cell, alongside forty five others for the complete set…" seems to assume that the listener will already know, or will readily appreciate, that in humans the genetic material is organised into 46 chromosomes (i.e., 23 pairs).
Arguably, someone who did not know this might infer it from the presentation itself. Perhaps they would. The core of the story was about how previous versions of 'the' [see note 1] human genome were not complete, and how new research offered a more complete version. The more background a listener had regarding the various concepts used in the item, the easier it would be to follow the story. The more unfamiliar ideas that have to be coordinated, the greater the load on working memory, and the more likely the point of the item would be missed.2
Getting in a tangle
A very common feature of human language is its figurative content. Much of our thinking is based on metaphor, and our language tends to be full [sic 3] of comparisons as metaphors, similes, analogies and so forth.
So, we can imagine 'a single chromosome' (something that is abstract and outside of most people's direct experience) as being like something more familiar: 'like a thread'. We can visualise, and perhaps have experience of, threads being 'wound up into extremely tight balls'. Whether DNA strands in chromosomes are 'wound up into extremely tight balls' or are just somewhat similar to thread wound up into extremely tight balls is perhaps a moot point: but this is an effective image.
And it leads to the idea of knots that might be pretty hard to untangle. We have experience of knots in thread (or laces, etc.) that are difficult to untangle, and it is suggested that in sequencing the genome such 'knots' need to be untangled in the laboratory. The listener may well be visualising the job of untangling the knotted thread of DNA – and quite possibly imaging this is a realistic representation rather than a kind of visual analogy.
Indeed, the reference to "some of the resulting knots it turns out are pretty hard to untangle in the lab. and the genetic patterns there are often hard to decode as well" might seem to suggest that this is not an analogy, but two stages of a laboratory process – where the DNA has to be physically untangled by the scientists before it can be sequenced, but that even then there is some additional challenge in reading the parts of the 'thread' that have been 'knotted'.
Reading the code
In the midst of this account of the knotted nature of the chromosome, there is a complementary metaphor. The single chromosome is "crammed with three hundred million genetic letters". The 'letters' relate to the code which is 'written' into the DNA and which need to be decoded. An informed listener would know that the 'letters' are the bases (often indeed represented by the letters A, C, G and T), but again it seems to be assumed this does not need to be 'spelt out'. [Sorry.]
But, of course, the genetic code is not really a code at all. At least, not in the original meaning of a means of keeping a message secret. The order of bases in the chromosome can be understood as 'coding' for the amino acid sequences in different proteins but strictly the 'code' is, or at least was originally, another metaphor. 4
Hitting the wall
The new research had progressed beyond the earlier attempts to sequence the human genome because that project had 'faced a wall' – a metaphorical wall, of course. This was the difficulty of sequencing regions of the genome that, the listener is told, were quite special.
The presenter suggests that the difficulty of sequencing these special regions of "hard to get at bits of genome" was akin to" trying to find a coin in the bottom of your pocket that you can't quite pull out". This is presumably assumed to be a common experienced shared by, or at least readily visualised by, the audience allowing them to better appreciate just how "hard to get at" these regions of the genome are.
We might pause to reflect on whether a genome can actually have regions. The term region seems to have originally been applied to a geographical place, such as part of a state. So, the idea that a genome has regions was presumably first used metaphorically, but this seems such a 'natural' transfer, that the 'mapping' seems self-evident. If it was a live metaphor, it is a dead one now.
Similarly, the mapping of the sequences of fragments of chromosomes onto the 'map' of the genome seems such a natural use of the term may no longer seem to qualify as a metaphor.
Repeats on steroids
These special regions are those referred to above as having tandem repeats – so parts of a chromosome where particular base sequences repeat (sometimes a great many times). This is described as "pieces of sequences that are found in a head to tail orientation" – applying an analogy with an organism which is understood to have a body plan that has distinct anterior and posterior 'ends'.
Not only does the genome contain such repeats, but in some places there are a 'tremendous' number of these repeats occurring head to tail. These places are referred to as 'corners' of the genome (a metaphor that might seem to fit better with the place in a pocket where a coin might to be hard to dislodge – or perhaps associated with that wall), than with a structure said to be like a knotted, wound-up, ball of thread.
It is suggested that in these regions, the repeats of the same short base sequences can be so extensive that they continue for billions of bases. This is expressed through the simile that the tandem repeating "is just on steroids" – again an allusion to what is assumed to be a familiar everyday phenomenon, that is, something familiar enough to people listening to help then appreciate the technical account.
Many people in the audience will have experience of being on steroids as steroids are prescribed for a wide variety of inflammatory conditions – both acute (due to accidents or infections) and chronic (e.g., asthma). Yet these are corticosteroids and 'dampen down' (metaphorically, of course) inflammation. The reference here is to anabolic steroid use, or rather abuse, by some people attempting to quickly build up muscle mass. Although anabolic steroids do have clinical use, abusers may take doses orders of magnitude higher than those prescribed for medical conditions.
I suspect that whereas many people have personal experience or experience of close family being on corticosteroids, whereas anabolic steroid use is rarer, and is usually undertaken covertly – so the metaphor here lies on cultural knowledge of the idea of people abusing anabolic steroids leading to extreme physical and mood changes.
Making a good impression
That is not to suggest this metaphor does not work. Rather I would suggest that most listeners would have appreciated the intended message implied by 'on steroids', and moreover the speaker was likely able to call upon the metaphor implicitly – that is without stopping to think about how the metaphor might be understood.
Metaphors of this kind can be very effective in giving an audience a strong impression of the scientific ideas being presented. It is worth noting, though, that what is communicated is to some extent just that, an impression, and this kind of impressionist communication contrasts with the kind of technically precise language that would be expected in a formal scientific communication.
Language on steroids
Just considering this short extract from this one item, there seems to be a great deal going on in the communication of the science. A range of related concepts are drawn upon as (assumed) background and a narrative offered for why the earlier versions of the human genome were incomplete, and how new studies are producing more complete sequences.
Along the way, communication is aided by various means to help 'make the unfamiliar familiar' by using both established metaphors as well as new comparisons. Some originally figurative language (mapping, coding, regions) is now so widely used it has been adopted as literally referring to the genome. Some common non-specific metaphors are used (hitting a wall, hard to access corners), and some specific images (threads, knots and tangles, balls, head-tails) are drawn upon, and some perhaps bespoke comparisons are introduced (the coin in the pocket, being on steroids).
In this short exchange there is a real mixture of technical language with imagery, analogy, and metaphor that potentially both makes the narrative more listener-friendly and helps bridge between the science and the familiar everyday – at last when these figures of speech are interpreted as intended. This particular extract seems especially 'dense' in the range of ideas being orchestrated into the narrative – language on steroids, perhaps – but I suspect similar combinations of formal concepts and everyday comparisons could be found in many other cases of public communication of science.
An alternative concept map of the extract, suggesting how someone with some modest level of background in the topic might understand the text (filling in some implicit concepts and connections). How a text is 'read' always depends upon the interpretive resources the listener/reader brings to the text.
At least the core message was clear: Scientists have now fully sequenced the human genome.
Although, I noticed when I sought out the scientific publication that "the total number of bases covered by potential issues in the T2T-CHM13 assembly [the new research] is just 0.3% of the total assembly length compared with 8% for GRCh38 [The human genome project version]" (Nurk et al., 2022) , which, if being churlish, might be considered not entirely 'fully' sequenced. Moreover "CHM13 lacks a Y chromosome", which – although it is also true of half of the human population – might also suggest there is still a little more work to be done.
Work cited:
Nurk, S., Koren, S., Rhie, A., Rautiainen, M., Bzikadze, A. V., Mikheenko, A., . . . Phillippy, A. M.* (2022). The complete sequence of a human genome. Science, 376(6588), 44-53. doi:doi:10.1126/science.abj6987
Notes
1 We often talk of DNA as a substance, and a molecule of DNA as 'the' DNA molecule. It might be more accurate to consider DNA as a class of (many) similar substances each of which contains its own kind of DNA molecule. Similarly, there is not a really 'a' human genome – but a good many of them.
2 Working memory is the brain component where people consciously access and mentipulate information, and it has a very limited capacity. However, material that has been previously learnt and well consolidated becomes 'chunked' so can be accessed as 'chunks'. Where concepts have been integrated into coherent frameworks, the whole framework is accessed from memory as if a single unit of information.
3 Strictly only a container can be full – so, this is a metaphor. Language is never full -as we can always be more verbose! Of course, it is such a familiar metaphor that it seems to have a literal meaning. It has become what is referred to as a 'dead' metaphor. And that is, itself, a metaphor, of course.
4 Language changes over time. If we accept that much of human cognition is based on constructing new ways of thinking and talking by analogy with what is already familiar (so the song is on the 'top' of the charts and it is a 'long' time to Christmas, and a 'hard' rain is going to fall…) then language will grow by the adoption of metaphors that in time cease to be seen as metaphors, and indeed may change in their usage such that the original reference (e.g., as with electrical 'charge') may become obscure.
In education, teachers may read originally metaphorical terms in terms of teir new scientific meanings, whereas learners may understand the terms (electron 'spin', 'sharing' of electrons, …) in terms of the metaphorical/analogical source.
*This is an example of 'big science'. The full author list is:
Sergey Nurk, Sergey Koren, Arang Rhie, Mikko Rautiainen, Andrey V. Bzikadze, Alla Mikheenko, Mitchell R. Vollger, Nicolas Altemose, Lev Uralsky, Ariel Gershman, Sergey Aganezov, Savannah J. Hoyt, Mark Diekhans, Glennis A. Logsdon,p Michael Alonge, Stylianos E. Antonarakis, Matthew Borchers, Gerard G. Bouffard, Shelise Y. Brooks, Gina V. Caldas, Nae-Chyun Chen, Haoyu Cheng, Chen-Shan Chin, William Chow, Leonardo G. de Lima, Philip C. Dishuck, Richard Durbin, Tatiana Dvorkina, Ian T. Fiddes, Giulio Formenti, Robert S. Fulton, Arkarachai Fungtammasan, Erik Garrison, Patrick G. S. Grady, Tina A. Graves-Lindsay, Ira M. Hall, Nancy F. Hansen, Gabrielle A. Hartley, Marina Haukness, Kerstin Howe, Michael W. Hunkapiller, Chirag Jain, Miten Jain, Erich D. Jarvis, Peter Kerpedjiev, Melanie Kirsche, Mikhail Kolmogorov, Jonas Korlach, Milinn Kremitzki, Heng Li, Valerie V. Maduro, Tobias Marschall, Ann M. McCartney, Jennifer McDaniel, Danny E. Miller, James C. Mullikin, Eugene W. Myers, Nathan D. Olson, Benedict Paten, Paul Peluso, Pavel A. Pevzner, David Porubsky, Tamara Potapova, Evgeny I. Rogaev, Jeffrey A. Rosenfeld, Steven L. Salzberg, Valerie A. Schneider, Fritz J. Sedlazeck, Kishwar Shafin, Colin J. Shew, Alaina Shumate, Ying Sims, Arian F. A. Smit, Daniela C. Soto, Ivan Sović, Jessica M. Storer, Aaron Streets, Beth A. Sullivan, Françoise Thibaud-Nissen, James Torrance, Justin Wagner, Brian P. Walenz, Aaron Wenger, Jonathan M. D. Wood, Chunlin Xiao, Stephanie M. Yan, Alice C. Young, Samantha Zarate, Urvashi Surti, Rajiv C. McCoy, Megan Y. Dennis, Ivan A. Alexandrov, Jennifer L. Gerton, Rachel J. O'Neill, Winston Timp, Justin M. Zook, Michael C. Schatz, Evan E. Eichler, Karen H. Miga, Adam M. Phillippy
Taking advantage of good design? (Image by Ben Kerckx from Pixabay )
"A lot of researchers talk about this [neural system] called the care-giving system which is designed to help us care for our crying babies".
Assoc. Prof. Sara Konrath
The reference to the 'design' of a human neural system caught my attention. The reference was made by Dr Sara Konrath, Associate Professor of Philanthropic Studies at the Lilly Family School of Philanthropy at Indiana University, who was interviewed for the BBC radio programme 'The Anatomy of Kindness'.
As a scientist, I found the reference to 'design' out of place, as it is a term that would often be avoided in a scientific account.
Mention of 'design' in the context of natural phenomena is of note because of the history of the idea, and its role in key philosophical questions (such as the nature of the world, the purpose of our lives, the origins of good and evil, and other such trifling matters).
The notion of design was very important in natural theology, which looked at 'the book of nature' as God's works, and as offering insight into God as creator. A key argument was that the intricacy of nature, and the way life seemed to encompass such complex interlinked systems that perfectly fitted together into an overarching ecology, could only be explained in terms of a designer who was the careful architect of the whole creation.
Perhaps the most famous example of this argument was that of William Paley who wrote an entire book (1802) making the case with a vast range of examples. He started with the now famous analogy of someone who found a pocket watch on crossing a heath. Had he kicked a stone on his trip, he would have thought little of how the stone came to be there – but a watch was a complex mechanism requiring a large number of intricate parts that had to be just the right size, made of the right kind of materials, and put together in just the right way to function. No reasonable person could imagine the watch had just happened to come about by chance events, and so, by a similar argument, how could anything as subtle and complex as a human body have just emerged by accident and not have been designed by some great intelligence?
If you came across this object lying on the ground, what might you infer? (Image by anncapictures from Pixabay)
Paley's book does a wonderful job of arguing the case, and, even if some of the examples look naive from two centuries on, it was the work of someone who knew a great deal about anatomy, and the natural history of his time, and knew how to build up 'one long argument'. 1 It must have seemed very convincing to many readers at the time (especially as most would have read it from a position of already assuming there was an omniscient and all-powerful creator, and that the types of animals and plants on earth had not substantially changed their forms since their creation).
Indeed, a fair proportion of the world's population would still consider the argument sound and convincing today. That is despite Charles Darwin having suggested, about half a century later, in his own long argument 1 that there was another alternative (than an intelligent designer or simply chance formation of complex organisms and ecosystems). The title of one of Richard Dawkin's most famous books, The Blind Watchmaker (1988), championing the scientific position first developed by Darwin (and Alfred Russel Wallace) is a direct reference to Paley's watch on the heath.
The modern scientific view, supported by a vast amount of evidence from anatomy, genetics, paleontology, geology and other areas is that life evolved on earth over a vast amount of time from common ancestral unicellular organisms (which it is thought themselves evolved from less complex systems over a very long period).
Has science ruled out design?
This does not mean that science has completely ruled out the possibility that modern life-forms could have been designed. Science does rule out the possibility that modern organisms were created 'as is' (i.e., 'as are'), so if they were designed then the designer not only designed their forms, but also the highly complex processes by which they might evolve and the contingencies which made this possible. (That can be seen as an even greater miracle, and even stronger evidence of God's capabilities, of course.) What science does not do is to speculate on first causes which are not open to scientific investigation. 2
Many of the early modern scientists had strong religious convictions – including faith in an intelligent creator – and saw science as work that was totally in keeping with their faith, indeed often as a form of observance: a way of exploring and wondering at God's work. Science, philosophy and theology were often seen as strongly interlinked.
However, the usual expectation today is that science, being the study of nature, has no place for supernatural explanations. Scientists are expected to adopt 'methodological naturalism', which means looking for purely natural mechanisms and causes. 3
Arguments from design invoke teleology, the idea that nature has purpose. This makes for lazy science – as we do not need to seek natural mechanisms and explanations if we simply argue that
the water molecule was designed to be a shape to form hydrogen bonds, or that
copper is a good conductor because its molecular structure was designed for that purpose, or that
uranium is subject to radioactive decay because the nucleus of a uranium atom was designed to be unstable
Science has (and so a scientist, when doing her science, should have) nothing to say about the existence of a creator God, and has no view on whether aspects of the natural world might reflect such a creator's design; so arguments from design have no place in scientific accounts and explanations. This is why I honed in on the reference to design.
The evolution of empathy?
The reference was in relation to empathy. The presenter, Dr Claudia Hammond, asked rhetorically "empathy … how did it evolve?", and then introduced an interview clip: "Here's Sara Konrath, Associate Professor at the Lilly Family School of Philanthropy at Indiana University in the U.S." This was followed by Dr Konrath stating:
"A lot of researchers talk about this thing called the care-giving system which is designed to help us care for our crying babies. So, think about a crying baby for a minute that is not your own. You are on an airplane, think about that. [She laughs] And probably what you are hoping for is that baby will stop crying, [Hammond: 'absolutely'], I guess.
We need to have a biological system that will make us feel compassion for that little crying baby and figure out what's wrong so we can make the baby feel better. So, there's a whole neural system that's called the care-giving system, that activates oxytocin which is a hormone that helps us to basically reduce stress and feel close and connected, and as you can imagine that would help us want to change that little nappy or whatever the baby needs. * And that same brain system doesn't seem to distinguish too much, well, you know, we can use that, that same system to care for other people in our lives that we know or even strangers, and even people who are different than us."
Assoc. Prof. Sara Konrath
Now, as pointed out above, accepting evolution (as the vast majority of natural scientists do) does not logically exclude design – but to be consistent it requires the design not only of the intended structure, but also of the entire natural system which will give rise to it. And evolution, a natural process, is open to scientific investigation, whereas claims of design rely on extra-scientific considerations. Moreover, as evolution is an ongoing process, one might suggest that references to 'this stage in the design-realisation process' might be more appropriate.
One way of explaining the apparent inconsistency here ("how did it evolve?"…"designed to help us") is to simply assume that I am being much too literal, as surely Dr Konrath was speaking metaphorically. We can talk about 'the design' of the kidney, or a flower, or of a cow's digestive system, meaning the structure, the layout, the assemblage – without meaning to suggest 'the design' had been designed. Although Dr Konrath referred to the neural system being designed, it is quite possible she was speaking metaphorically.
But can we beleive what we (think we) hear?
A listener can reasonably assume, from the editing of the programme, that Dr Konrath was asked, and was answering, the question 'how did empathy evolve?' Yet this is only implied ("…how did it evolve? Here's Sara Konrath…") – the clip of Dr Konrath does not include any interview questions.
A journalist has to edit a programme together, to offer a narrative a listener can easily follow, so it is likely an interview would be edited down to select the most useful material. Indeed, when transcribing, I suspected that there was an edit at the point I have marked * above. I could not hear any evidence of an edit, BUT to my ears the speech was not natural in moving between "…whatever the baby needs" and "And that same brain system…". Perhaps I am wrong. But, perhaps there was a pause, or a 'false start', edited out to tidy the clip; or perhaps some material deemed less pertinent or too technical for present purposes was removed. Or, possibly, the order of the material has been changed if the speaker had responded to a number of questions, and it was felt a re-ordering of segments of different responses offered a better narrative.
All of that would be totally acceptable, as long as it was done without any intention to distort what the speaker had said. Indeed, in analysing and presenting research material from interviews or written texts, one approach is known as editing. 4 I have used this myself, to select text from different points in an interview to build up a narrative that can summarise an informant's ideas succinctly (e.g., Taber, 2008 5). This needs to be done carefully, but as long as an effort is made to be true to the person's own ideas (as the researcher understands them from the data) and this methodological technique is explicitly reported to readers, it is a valid approach and can be very effective.
Perhaps, if Dr Konrath was indeed asked 'how did empathy evolve?' this was a rather unfair question. Unlike some anatomical structures, empathy does not leave direct evidence in the fossil record. This might explain a not entirely convincing response.
The gist of the clip, as I assume a listener was meant to understand it, was along the lines.
How did empathy evolve?
babies cannot look after themselves and need support
they cry to get attention when they need help
a system evolved to ensure that others around the baby would pay attention to its cries, and feel compassionate, and so help it
the system either has the side effect of, or has evolved over time, allowing us to be empathetic more generally so we support people who need help
Perhaps that narrative is correct, and perhaps there is even scientific evidence for it. But, in terms of what I actually hear Dr Konrath say, I do not find a strong evolutionary account, but rather something along the lines:
We have a biological system known as the care-giving system, that activates a hormone that reduces stress and helps us feel close and connected to others
this allows us to feel compassion for people in need
encouraging us to care for other people, largely indiscriminately
even strangers, such as a crying baby
When I reframe ('edit') the interview that way, I do not see any strong case for why this system is designed specifically to help us care for our crying babies – but nor is there any obvious evolutionary argument. 6
If one approaches this description with a prior assumption that such things have evolved through natural selection then Dr Konrath's words can certainly be readily interpreted to be consistent with an evolutionary narrative. 6 However, someone who did not accept evolution and had a metaphysical commitment to seeing the natural world as evidence for a designer would surely be able to understand the interview just as well within that frame. I suspect both Paley and Darwin would have been able to work this material into their arguments.
Works cited:
Darwin, C. (1859/2006). The Origin of Species. In E. O. Wilson (Ed.), From so Simple a Beginning: The four great books of Charles Darwin. New York: W. W. Norton.
Dawkins, R. (1988). The Blind Watchmaker. Harmondsworth, Middlesex: Penguin Books.
Paley, W. (1802/2006). Natural Theology: Or Evidence of the Existence and Attributes of the Deity, Collected from the Appearances of Nature (M. D. Eddy & D. Knight Eds.). Oxford: Oxford University Press.
Taber, K. S. (2008). Exploring Conceptual Integration in Student Thinking: Evidence from a case study. International Journal of Science Education, 30 (14), 1915-1943. (DOI: 10.1080/09500690701589404.)
1 The term 'one long argument' was used by Darwin to describe his thesis in the Origin of Species.
2 I write loosely here: science does not do anything; rather, it is scientists that act. Yet it would not be true to claim scientists do not speculate on first causes which are not open to scientific investigation. Many of them do. (Dawkins, for example, seems very certain there is no creator God.) However, that is because scientists are people and so have multiple identities. Just as nothing stops a scientist also being a mother or a daughter; nothing stops them being ice skaters, break dancers or poets. So, scientists do speculate outside of the natural realm – but then they are doing something other than science, as when they write limericks. (And perhaps something where their scientific credentials suggest no special expertise.)
3 Unfortunately, this can mislead learners into thinking science is atheistic and scientists necessarily atheists:
"The tradition in Western science (with its tendencies towards an analytical and reductionist approach) to precede as though the existence and potential role of God in nature is irrelevant to answering scientific questions, if not explicitly explained to students, may well give the impression that because science (as a socio-cultural activity) does not need to adopt the hypothesis of the divine, scientists themselves (as individuals sharing membership of various social groups with their identities as scientists) eschew such an idea."
4 This process would need to be made explicit in research, where it is normally just accepted as standard practice in journalism. These two activities can be seen as quite similar, especially when research is largely based on reports from various informants. A major difference however is that whereas researchers often have months to collect, analyse and report data, journalists are often expected to move on to the next story or episode within days, so may be working under considerable time pressures.
5 For example,
"Firstly the interview transcript was reworked into a narrative account of the interview based around Alice's verbatim responses, but following the chronology of the interview schedule in the order of the questions….The next stage of the analysis involved reorganising the case material into themes in terms of the main concepts used in Alice's explanations…This process produced a case account that was reduced (in this case to about 1,000 words), and which summarises the ways Alice used ideas in her interview."
Taber, 2008: 1926
6 One can imagine researchers asking themselves how this indiscriminate system for helping others in need arose, and someone suggesting that perhaps it was originally to make sure mothers attended to their own babies, but as a 'false negative' would be so costly (if you do not notice your baby is unfed, or has fallen in the lake, or is playing with the tiger cubs…) the system was over-sensitive and tolerated 'false positives' (leading to people attending to unrelated babes in need), and even got triggered by injured or starving adults – which it transpired increased fitness for the community, so was selected for…
It can be much easier to invent feasible-sounding evolutionary 'just-so stories' than rigorously testing them!
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.
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'
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.
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:
Cervia, C., Zurbuchen, Y., Taeschler, P. et al.(2022) Immunoglobulin signature predicts risk of post-acute COVID-19 syndrome. Nature Communications, 13, 446. https://doi.org/10.1038/s41467-021-27797-1
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.
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.
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…')
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.
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"Â 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.
"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
Â
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 –Â 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?
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.
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).
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').
In my work I've spent a lot of time analysing the things learners say about science topics in order to characterise their thinking. Although this work is meant to have an ethnographic feel, and to be ideographic (valuing the thinking of the individual in its own terms), there is always an underlying normative aspect: that is, inevitably there is a question of how well learners' conceptualisations match target curricular knowledge and canonical science. We all have intuitions which are at odd with scientific accounts of the world, and we all develop alternative conceptions – notions which are inconsistent with canonical concepts.
Peter and Patricia started seeing each other at this local fence earlier this year.
Soon passion got too much for them and they (publicly) consummated their relationship on this very fence (some birds have no shame).
It is easier to spot this in others (you think what?!) than it is in ourselves. But occasionally you may reflect on the way you think about a topic and recognise aberrations in your own thinking. One of these examples in my own thinking relates to bird's nests. I know that birds build nests as a place to lay and hatch eggs. Using the ground would be very dangerous due to vulnerability to predators. Simply using branches would be precarious – especially as eggs are hardly best shaped to be balanced on a tree branch. I also know that once the young are fledged have fled the nest, it has outlived its purposes.
They quite liked the area, and decided to look for a place nearby.
Soon they had identified a nice place to build their new home in some nearby ivy.
Yet it was only a few years ago – I think when came across discarded nests in the garden – that I released I have carried around with me since quite young the metaphor that a nest is a bird's home – it is where the bird family lives. Perhaps I made up that idea as a child. More likely I was told that or heard it on a children's programme. If so, perhaps it was not meant to be taken too literally – it was just meant to compare the nest with something that would be familiar to a child. But I think well into adulthood I had this notion of that birds lived in trees – not explicitly, but insidiously in the back of my mind: as if a bird had a home in a tree and that was where it was based – unless and until perhaps it could afford to move upmarket to a better tree!
They decided to do their own build, which involved Peter in the tiring work of going out to get building materials.
Peter set about the serious business of setting up their new dream home.
Peter was quite confident, and would often return which rather large pieces of nesting material.
"Oh, that seems to have got caught up."
Over time Peter started to be more realistic in selecting material he could get through the front door.
Although I was well aware (at one level) that birds do not have permanent family homes to which they return at the end of a hard day's exertions, I also had this nest=home identity at the 'back of my mind' giving the impression that this is how birds live. As humans we take for granted certain kinds of forms of life (perhaps home, work, family, etc.), and these act as default templates for understanding the world. This makes anthropomorphising nature seem quite a natural thing to do.
Peter heading out to work, again.
And getting home with his latest acquisition – landing on his feet.
Watching this process develop was quite entertaining. Peter would spend ages pecking at pieces of plant that were firmly fixed in the ground, ignoring nearby loose material. His early attempts to take material back to the nest were troubled. He would take material that was too large to get through the foliage into the secluded nesting area. He would also fly close to 'home' and then abort as found he could not land with his goods. However, he soon seemed to learn what worked, and developed a technique of first flying onto the fence or the roof the ivy was growing on to, so he would not be flying up to the nesting place from the ground in a single stage.
The sequences below show the pigeon flying out from, and back to, the nest.
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The jumping/diving action is clear in the sequence below:
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The fourth and fifth frames in the sequence below show the 'landing gear' coming into position (reminiscent of a bird of prey taking its prey):
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The landing action is also clear near the end of the sequence below:
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Another take off. catching the first few flaps:
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My favourite sequence – quite extended for my hand-held camera work! – in the 11th frame our pigeon is just entering frame right. But notice a sparrow sitting on top of the foliage to the left. The sparrow has presumably seen/heard the much larger bird comings it way, and in the next frame can be seen to be moving its wings ready to take off. The next three frames have the sparrow heading right as the pigeon moves to the left (the sparrow is a smudge beneath the pigeon's left wing in the third of these frames), and the sparrow appears to have disappeared from view in the next, but must have been obscured by the pigeon as it seen to the right of the next frame. The sequence ends with the pigeon in landing mode.
Sandra was a participant in the Understanding Science Project. When I interviewed Sandra about her science lessons in Y7 she told me "I've done changing state, burning, and we're doing electricity at the moment". She talked about burning as being a chemical change, and when asked for another example told me dissolving was a chemical change, as when salt was dissolved it was not possible to turn it back to give salt grains of the same size. She talk me that is the water was boiled off from salt solution "you'd have the same [amount of salt], but there would just be more particles, but they'd be smaller".
As Sandra had referred to had referred to the salt 'particles' being smaller,(as as she had told me she had been studying 'changing state') I wondered if she had bee taught about the particle model of matter
So the salt's got particles. The salt comes as particles, does it? Yeah. Do other things come as particles? Everything has particles in it. Everything has particles? Yeah. But with salt, you can get larger particles, or smaller particles? Well, most things. Like it will have like thousands and thousands of particles inside it. So these are other types of particles, are they? Mm.
So although Sandra had referred to the smaller salt grains as being "smaller particles", it seemed he was aware that 'particles' could also refer to something other than the visible grains. Everything had particles in. Although salt particles (grains?) could be different sizes, it (any salt grain?) would have a great number ("like thousands and thousands") of particles (not grains – quanticles perhaps) inside it. So it seemed Sandra was aware of the possible ambiguity here, that there were small 'particles' of some materials, but all materials (or, at least, "most things") were made up of a great many 'particles' that were very much smaller.
So if you look at the salt, you can see there's tiny little grains? Yeah. But that's not particles then? Well it sort of is, but you've got more particles inside that.
"It sort of is" could be taken to mean that the grains are 'a kind of particle' in a sense, but clearly not the type of particles that were inside everything. She seemed to appreciate that these were two different types of particle. However, Sandra was not entirely clear about that:
So there's two types are of particles, are there? I don't know. Particles within particles? Yeah. Something like that, is it? Yeah. But everything's got particles has it, even if you can't see them? Yeah. So if you dissolved your salt in water, would the water have particles? Ye:ah. 'cause I've seen water, and I've never seen any particles in the water. The part¬, you can't actually see particles. Why not? Because they're too small. Things can be too small to see? Yeah. Oh amazing. So what can you see when you look at water, then? 'cause you see something, don't you? You can see – what the particles make up. Ah, I see, but not the individual particles? No.
Sandra's understanding here seems quite strong – the particles that are inside everything (quanticles) were too small to be seen, and we could only see "what the particles make up". That is, she, to some extent at least, appreciated the emergence of new properties when very large numbers of particles that were individually too small to see were collected together.
Despite this, Sandra's learning was clearly not helped by the associations of the word 'particle'. Sandra may have been taught about submicroscopic particles outside of direct experience, but she already thought of small visible objects like salt grains as 'particles'. This seems to be quite common – science borrows a familiar term, particle, and uses it to label something unfamiliar.
We can see this as extending the usual everyday range of meaning of 'particle' to also include much smaller examples that cannot be perceived, or perhaps as a scientific metaphor – that quanticles are called particles because they are in some ways like the grains and specks that we usually think of as being very small particles. Either way, the choice of a term with an existing meaning to label something that is in some ways quite similar (small bits of matter) but in other ways very different ('particles' without definite sizes/volumes or actual edges/surfaces) can confuse students. It can act as an associative learning impediment if students transfer the properties of familiar particles to the submicroscopic entities of 'particle' theory.
All images from '
