June 1, 2018, by Brigitte Nerlich
Bacteria, metaphors and responsible language use
A lot has been written about the war on bacteria, especially in the context of antimicrobial resistance. Some articles reflect on the metaphor of war in medicine and in microbiology more generally, others deal with the metaphors of bacterial communication and communities. A few papers look more closely at the way bacteria are anthropomorphised in the lab.
So far nobody seems to have studied an emerging trend in microbiology and synthetic biology noted by microbiologist and synthetic biologist Victor de Lorenzo, namely the use of strongly ideologically tinged metaphors to talk about how bacteria ‘behave’.
Here are four examples spotted by Victor: (1) “Conditional privatization of a public siderophore enables Pseudomonas aeruginosa to resist cheater invasion”; (2) “Strategic investment explains patterns of cooperation and cheating in a microbe“; (3) “Privatisation rescues function following loss of cooperation”, and (4) “Bacteria Use Collective Behavior to Generate Diverse Combat Strategies”. (To which one could also add: “Microbiology: Bacterial communities as capitalist economies“) Having noted these titles, Victor asks a number of increasingly urgent questions:
On 12 and 13 April he muses: “I get a bit unsettled when scientists abuse metaphors by attributing typical human actions & qualities 2 bacteria: cheater, public goods, quorum, invasion, privatisation. The choice of words & metaphors imposes interpretive frames that can be misleading“ and “I keep on freaking out re the title of this paper. It looks like if Pseudomonas were a Right-wing party that decides 2 privatize a former common good (medicaments?) as a way to deter cheating invaders (immigrants?) from using the social system. Ideological metaphors—aren’t they?”.
On 8 May he wonders about the “language & categories of capitalism in Microbiology. It’s difficult to avoid contamination of scientific narratives with ideology. Are postmodern thinkers right & everything is just interpretation?” On 20 May he exclaims: “Oh no! Once more time military metaphores for describing bacterial behaviour […] … We had before capitalist metaphors. Is another, not ideologically loaded jargon possible for the microbial world?” A few days later, on 23 May, he notes again: “Unchecked adoption of capitalist jargon and metaphores in Microbiology seems not to have an end”.
In the following I’ll look a bit more closely at capitalist metaphors, leaving aside military ones for another time.
The use or abuse of metaphors
There is a lot of food for thought in those tweets and probably a lot more in the articles that Victor highlighted. An in-depth study of these will have to wait for the summer.
But just take this extract from the article on strategic investment: “Contributing to cooperation is costly, while its rewards are often available to all members of a social group. Therefore, cooperation is vulnerable to exploitation by individuals that do not contribute but nevertheless share the benefits. So why contribute to cooperation? This dilemma can be resolved if individuals modulate their ‘investment’ into cooperation dependent on whether benefits go to relatives or nonrelatives, which maximizes the return on investment to their genes. To evaluate this idea, we derived a model for cooperative investment and tested its predictions using a social microbe that cooperatively builds a stalk to facilitate spore dispersal. We find that cooperative investment into stalk closely matches predictions, with strains strategically adjusting investment according to their relatedness to their group.” (Italics added)
Could this paper have been written without the ‘strategic’ use of these metaphors? Indeed, could the research reported in this and the other articles listed above have been undertaken without using metaphors as searchlights?
If it’s impossible to think about these matters without using metaphors, could there be alternative ones that do not use phrases like ‘return on investment’, ‘privatisation’, ‘cheaters’, ‘selfish’, ‘invasion’ or ‘combat strategies’, i.e. metaphors that do not have an ideological, militarist or capitalist tinge? Are (conventional) metaphors like ‘cooperation’ and ‘communication’ less suspicious?
I am just asking these questions so as to elicit some discussion. I don’t really know the answers myself! However, there might be some clues as to what’s happening…
Behavioural economics and bacterial behaviour
One thought occurred to me when reflecting on these metaphors (and of course more research and actual reading needs to be done, which I can’t do yet): Some of the metaphors used in the flagged-up articles seem to have their roots in game theory and behavioural economics, where one hears for example about cooperators and defectors, or costs and benefits, or trade-offs and public goods, and so on.
Game theory in particular seems to be quite a rich seam for rather creative metaphors in microbiology. Once writers have discovered this novel ‘source domain’ for metaphors they can mine it quite creatively to talk about their ‘target domain’, namely the behaviour of bacteria.
There is, of course, also the possibility that the topic, namely evolution and ‘behaviour’ of bacteria, can, indeed, be studied directly, not just metaphorically, through the lens of game theory, indeed evolutionary game theory. This might be where (mathematical) models and metaphors meet.
This seems to be the case in the ‘conditional privatization‘ article which starts with the following statement: “Natural selection and game theory predict that cooperative behaviors are vulnerable to the exploitation of common resources by selfish individuals because selfish individuals (cheaters) consume common resources to gain benefits without contributing fairly.”
Responsible language use
The question then becomes: Does this creative use of metaphors encourage novel scientific insights? And if so, are these new insights responsibly framed? Or are there dangers in adopting a jargon that appears to be rooted in capitalist ideology?
As Victor rightly points out in yet another tweet: “Like hypotheses: all metaphors are ultimately wrong, but some are useful. Problem is that some are also misleading as they frame our thoughts within given boundaries”.
Are the metaphors inspired by game theory and behavioural economics misleading or do they lead to better insights? Are they used responsibly or irresponsibly? Do they impose ideological boundaries or do they let researchers cross boundaries between conceptual domains in new and creative ways?
Answers on a postcard, please!
de Lorenzo, V. (2011). Beware of metaphors: Chasses and orthogonality in synthetic biology. Bioengineered Bugs, 2(1), 3-7.
de Lorenzo, V. (forthcoming). Evolutionary tinkering, vs rational engineering in the times of Synthetic Biology. Life Sciences, Society and Policy. (Article for thematic series on synthetic biology, metaphor and responsibility edited by Carmen McLeod and Brigitte Nerlich)
Image: Cultures of Pseudomonas syringae van Hall taken from bean halo blight colonies
Thanks for the great article, I found it very interesting.
I would agree that some of these metaphors go a bit too far (particularly the military ones), but on the whole I don’t see a problem. These are very standard terms in behavioural ecology, economics, and game theory (as you discuss), where nobody considers them to have sinister ideological undertones. Terms from economics such as ‘public’ or ‘private’ goods, and terms from behavioural ecology such as ‘cheater’ or ‘cooperator’ are simple descriptions, easily applicable across the tree of life. I see no reason why humans would hold exclusive domain over these actions. And only by providing a very narrow definition is this the case, which would itself be subscribing to a biased human-centric view of life. Furthermore, terms such as ‘cooperate or cheat’ or ‘public or private’ or ‘selfish or altruistic’ are all two-sides of the same coin, and it is preferring one metaphor over the other that would be ideological, by setting out a structure for how things should be discussed in science; rather than allowing the terms to be used as they always have been; as descriptions of behaviour or descriptions of resources. Behavioural ecology has always stressed that we are talking about behaviour as a response to a stimulus, not as some kind of emotion or morality that may be unique to humans. This is how we can generate broad insights and link studies between different taxa, it is categorically not anthropomorphism to describe how microbes respond to stimuli using the language of behavioural ecology. We must also remember the importance of science communication, where discussing how strains of bacteria can cheat to exploit the resource of the group provides an intuitive and engaging viewpoint
Microbiology is where social evolution is focused right now, for all kinds of reasons (see this article https://www.nature.com/articles/nrmicro1461) chief among which is the fact that microbes perform the same types of behaviours we see in animals, and compete for the same types of resources, whilst providing greater opportunity for experimental manipulation. It is my opinion that the real language problem is in the long-overdue melding of the worlds of microbiology and social evolution, and the probable lack of communication between these fields
I have to say, I agree with everything you say! Have you written about this somewhere?
Thank you so much for your thoughtful comment. I am out and about at the moment but will digest it properly when home.