Blute Blog

James Watson of the Watson and Crick “double helix” fame died recently at 97. Read the obituaries – he was a human being with great strengths but also with some weaknesses as well. I met him once briefly in 1990 when I participated in the Centennial Symposium on Evolution at the Cold Spring Harbor Laboratory while he was director there. What I loved about genetics as I continued to explore cultural evolution was the detailed analogy between genetics and linguistics. Some of that may have been forgotten more recently in the also important current emphasis on extending evolutionary theory, making it more inclusive beyond just population genetics.

Both genomes and languages are digital having basic units of structure (nucleotide bases and phonemes respectively) and basic units of function (codons and morphemes respectively). In both there are larger more inclusive units of both kinds as well and in both the units of function are symbolic rather than iconic. There is no physiochemical necessity in the biological case, nor psychological necessity in the cultural case, for the link between a string of symbols and what they represent. In both cases, those linkages are a product of an historical, evolutionary process and could well have been different under different circumstances. A language is a cultural species in which members are able to exchange communications linguistically within its boundaries but not beyond them analogous to a biological species with members able to exchange genetic information within but not beyond its boundaries. 

Sometimes authors seem to choose titles for books, or at least the first part of the titles, because they are grabby even though they do not accurately reflect the books’ contents. Two books like that I have been reading lately are Geoffrey Hodgson’s “From Marx to Markets: An Intellectual Odyssey”, (2025), Edward Elgar Publishing Limited, and Mark Vellend’s “Everything Evolves: Why Evolution Explains More Than We Think, From Proteins to Politics”, (2025), Princeton University Press.

The first part of both titles, “From Marx to Markets” and “Everything Evolves”, both tend to grab one’s attention, perhaps in part because of the opening rhymes – Ma in the former and Ev in the latter, but both are misleading. “From Marx to Markets” would lead one to expect that the author’s political views moved from far left to far right. “Everything Evolves” would lead one to expect that the author thinks that well, everything evolves. But in neither case do those reflect the books’ contents.

The first half or so of Hodgson’s book is a wonderful “intellectual odyssey”, a political autobiography set in the context of British and international politics of the times. However, it details his move from socialism to what he calls “liberal solidarity”. “We need a mixed economy where state regulation and some public ownership exist alongside a private sector and markets, reaping the benefits of regulated competition”. And elsewhere, “a mixed, regulated economy with a strong welfare state”. The second half or so of the book is not chronological, but a series of deeply researched and informative essays on definitions, evolutionary economics, institutional analysis, socialism versus liberal solidarity, and economics for a better world. The central thesis of Vellend’s book is that there really are only two sciences – physics and evolution. Little attention is then given to the former, instead the book is about how the “second science” is everywhere else – in all things cultural as well as biological – languages, technologies, and political systems for example. In fact, he emphasizes that he gives no priority to any discipline which is part of the second science including biology.

Actually, a more accurate first part of the title for Hodgson’s book would be “From Marx to the Middle” and for Vellend’s book would be “Everything Else Evolves”. Despite that, I think I like the titles better as they are! Does that mean I value aesthetics over accuracy? Perhaps. Anyway, do not misunderstand me. Despite the misleading first half of the titles, both books are highly recommended.

I have made reference to this in connection with density-dependence in various talks and papers but usually do not burden the audience with the math, even though it is simple. But I have been asked about it from time to time so here it is from the original source in my book.

“The surface area of a sphere = 4π r² while the volume = 4/3π r³. Hence the ratio of A/V = 3/r so that as a sphere becomes smaller (r approaches 0), the surface to volume ratio approaches ∞ and as it becomes larger (r approaches ∞) the surface to volume ratio approaches 0. Hence small organisms have a proportionately greater surface area for their volume (and at constant cytoplasmic densities, for their mass) than do large ones – surface area which can be utilized for feeding, sensing food etc. Conversely, large organisms have a proportionately greater volume (and at constant cytoplasmic densities, greater mass) for their surface area than do small ones – volume and mass that can be employed for complex internal digestive processes.” (Blute, 2010: 58).

Similar principles apply socioculturally. So for example, the members or staff of small organizations necessarily interact more with those externally, while those of large organizations necessarily interact more with those internally.

Blute, M. (2010) Darwinian Sociocultural Evolution: Solutions to Dilemmas in Cultural and Social Theory. Cambridge University Press

There is a contradiction in common assumptions about demographic values. Consider the three topics in Table 1, density-dependence relative to resources in row 1, the human demographic transition in row 2, and conventional sex roles in row 3. With respect to density-dependence, we typically view low density-dependence relative to resources i.e. plentiful resources as good conditions and high density relative to resources i.e. scarce resources as bad conditions. But with respect to the human demographic transition, we typically view before the transition (e.g. foraging or hunting and gathering societies) as bad conditions and after (eventually modern industrial societies) as good conditions. With respect to conventional sex differences i.e. with males producing more numerous potential offspring at low cost per capita (microgametes or sperm), and females producing fewer potential offspring at high cost per capita (macrogametes or eggs), we consider them as neither good nor bad, just different. Yet despite these intuitively different evaluations in each row, in fact all three in the same column are empirically the same – high fertility and mortality in situation 1 and low fertility and mortality in situation 2. So much for our intuitive evaluations!

What is wrong with those evaluations in each case? With respect to density-dependence, low and high density relative to resources are neither good nor bad, just different conditions in which selection favours different strategies – reproductively for example, producing offspring versus re-producing. The latter in a patchy environment serves the function of producing offspring which are capable of seeking out plentiful resources by means of the 3M’s – maintenance, motility and/or mutability and hence of producing grand-offspring (1, 2). With respect to the human demographic transition, foraging societies may not have been so bad after all, people there had lots of contact with nature, and industrial societies may not be so great. There one often must be patient and wait, move, or innovate. With respect to common basic sex differences, we commonly do recognize that they are neither good nor bad, just different, which is how we would view all three cases were we consistent.

There is a lesson here provided by Max Weber, the great nineteenth-century sociologist in two famous essays – one on “science as a vocation” and the other on “politics as a vocation” (3). Weber argued that science cannot answer questions of value. Slogans such as “value free science” are misleading however, because while science itself cannot answer questions of value, it can be brought to bear on them. Given an end, science may be able to tell us how to achieve it. Given a means, it may be able to tell us what its consequences are likely to be. And given two ends or two means, it may be able to tell us whether they are compatible. But science cannot, in and of itself, tell us what we should value.

1 Blute, M (2016). Density-dependent selection revisited: mechanisms linking explanantia and explananda. Biological Theory 11(2), 113-121.

2 Blute, M (2023). Costs as a key but too often neglected component of evolutionary theory. Biological Theory 18(2), 77-80.

3 Gerth, H. H., & Wright Mills, C. eds. (1958). From Max Weber: Essays in Sociology. Oxford University Press, Oxford.

For r & r I have been reading the new history of the Scopes ‘monkey trial’ by Brenda Wineapple, “Keeping the Faith: God, Democracy, and the Trial that Riveted a Nation” published in 2024 by Random House. You may recall that the trial was of John C. Scopes in 1925 in Tennessee for breaking a law passed by the state legislature forbidding the teaching of evolution in state schools. Scopes was found guilty and fined. The book is a good read and full of great quotes, especially from Clarence Darrow, his legal defender. One I made a note of was from co-defender Kirtley Mather who quoted Henry Ward Beecher:

“The theory of evolution is the working theory of every department of physical science all over the world. Withdraw this theory, and every department of physical research would fall back into heaps of hopelessly dislocated facts, with no more order or reason or philosophical coherence than exists in a basket of marbles, or in the juxtaposition of the multitudinous sands of the seashore. We should go back into chaos if we took out of the laboratories, out of the dissecting rooms, out of the field of investigation, this great doctrine of evolution.” Today we would say life or biological not physical science, but I could not help but wonder, what about social science?

The book also reminded me of a later 1981 case, McLean versus the Arkansas Board of Education over a law mandating the balanced treatment of “creation-science” and “evolution-science” in public schools. Michael Ruse, philosopher of science, and specifically of biology, founder of the great journal Biology and Philosophy among other things, and who taught at the University of Guelph here in Ontario for many years before retiring and going to Florida State University, testified. He convinced the federal judge that creation science is not science and the judge ruled that teaching creation science in public schools is unconstitutional. Later after another case in Louisiana in 1987, the Supreme Court agreed. There I could not help but wonder what would today’s U.S. Supreme Court rule?

I mistakenly put an “a” before “grandeur” in the concluding words of the Origin in my book and elsewhere originally. The full original quote is:

“There is grandeur in this view of life, with its several powers, having been originally breathed into a few forms or one; and that, whilst this planet has gone cycling on according to the fixed law of gravity, from so simple a beginning endless forms most beautiful and most wonderful have been, and are being, evolved.

Nature recently published an editorial arguing that busy scientists need more time to think. Hear hear!

I was saddened to read in the New York Times recently of the death of Fran de Waal of Emory University and the Yerkes Primate Research Centre at age 75. I have not read all of his more recent books nor would I probably agree with all of his reflections on animal cognition, especially his apparent recent skepticism about science. However, I certainly remember being impressed by his early experimental proof that chimps can learn socially by observation. He and some colleagues created a puzzle that was too difficult for members of two groups to solve. But then they took an individual from each group and trained them separately to solve it with individual learning methods, but differently. When they put the two back in the separate groups, the members of each group learned to do so – definitely by observation because each group learned the specific method of the model placed in their group.

I was so impressed that when decades ago I was in charge briefly of a dinner with a guest speaker held annually at my University of Toronto campus, I invited de Waal to speak and enjoyed his visit immensely.

Now I see in Nature on March 21 of this year that Bridges et. al. have performed a similar experiment successfully on, guess what, bumblebees!

In 2016 I published an article on “density-dependent selection revisited: mechanisms linking explanantia and explananda” in Biological Theory. Levels of selection was discussed there briefly, but only to argue that when a new level is added, the old does not disappear but becomes part of the mechanism of development of the new. The point I would like to make here is the more general one that density-dependence is an ecological theory which can be applied to multilevel selection which makes it unlike any others that I am aware of.

To summarize briefly, the theory was that (assuming somatic and reproductive functions utilize the same resource and that they interact cooperatively) low density relative to resources i.e. plentiful resources favour consumption (eating and excreting) and producing many small offspring. High density relative to resources (i.e. scarce resources), on the other hand, favour digestion (breaking down and building up for maintenance, motility and mutability – the 3 M’s) and re-producing (producing a few large offspring capable of giving rise to grand-offspring). The reason for these is that the small and/or those with short, fast life cycles (the r selected) have a disproportionate surface area relative to volume while the large and/or those with long, slow life cycles (the K selected) have a disproportionate volume relative to surface area. The former is good for consuming and producing while the latter is good for digesting and re-producing. What does that mean for multi-level selection? Obviously in retrospect, it means that plentiful resources favour lower levels (individuals within groups) and scarce resources favour higher levels (groups themselves).

Viewed from the ecological perspective of density-dependent selection then, it is no wonder that members of flocks of birds, schools of fish, herds of deer etc. commonly hang out together waiting for tough times to improve, or migrate together, or sometimes innovate together – the 3M’s. Indeed, if density relative to resources and those relative to antagonists both matter and are positively correlated in time and space, it should not be surprising to see, as we do, that such flocks, schools, herds etc. repeatedly migrate together between good feeding and good breeding grounds.

On the other hand, major transitions in evolution such as a transitions from unicellular to multicellular organisms are cases in which this approach to multilevel selection may be difficult to justify. If we assume that new more inclusive entities have an outer membrane, the consumption (eating and excreting) of the small would have to take place at some cost to the large, and the digestion (breaking down and building up) of the large would have to take place at some cost to the small – all of which would make them different situations from cases in which the two are separate. However that may not be a fatal flaw – after all, for the low density case, some cells do die during multicellular development without the whole doing so and for the high density case, some large and/or long-lived multicellular organisms do under go senescence without becoming extinct.

At a conference, I was recently asked why in my paper on a theory of sexual selection, I proposed that conventional sex between males and females is trade in which males include females as well as males among their offspring and females include males as well as females among their offspring. Of course the reason given was the proposal that there are some naturally-selected differences between them, and that under uncertainty, such trade reduces the risk of extinction like investing in an index fund rather than trying to pick stocks or dollar cost averaging rather than trying to time markets. However, the point of the query was why specify the function as trading the sex of some offspring rather than just creating (explicitly or implicitly genetic) variation which is the most common explanation.

The reason was that there are so many genetic (and environmental) mechanisms of sex determination, many more than the familiar XY and ZW systems, many of which remain unknown, even mysterious. My way for simplicity’s sake was to take what is known as “the phenotypic gambit”. If one is willing to assume that the often many genes involved in influencing a trait have an additive effect on fitness, then that effect will be heritable and hence available for natural selection to work on. Under those conditions then, one can speak of the evolution of observable characteristics such as those of males and females and not just of genes.