Thursday, 24 November 2016

Douglas Futuyma: no evolution revolution

Evolutionary revolutionaries face opposition from conservatives, who apparently like their evolutionary theory the way they were taught it in school. A case in point is Douglas Futuyma, well known as the author of a popular evolutionary biology textbook.

In the essay Can Modern Evolutionary Theory Explain Macroevolution? (see the "sample pages" link at the bottom of the page for the free PDF), Futuyma explains his perspective on various proposed changes to evolutionary theory - including changes proposed by students of cultural evolution. Thanks are due to Jerry Coyne for drawing attention to this paper.

The abstract starts:

Ever since the Evolutionary Synthesis of the 1930s and 1940s, some biologists have expressed doubt that the Synthetic Theory, based principally on mutation, genetic variation, and natural selection, adequately accounts for macroevolution, or evolution above the species level.

...and concludes:

I conclude that although several proposed extensions and seemingly unorthodox ideas have some merit, the observations they purport to explain can mostly be interpreted within the framework of the Synthetic Theory.
I think the essay goes after the wrong targets. The biggest change in our understanding of evolution since the 1930s has been the massive expansion of the domain of evolutionary theory - to include the Darwinian evolution of cultural variation, learned knowledge development systems and inorganic systems. Futuyma's treatment of this consists of a section entitled "Nongenetic Inheritance" - which mentions cultural inheritance, saying "Cultural characteristics such as language and wealth are nongenetically inherited". However he spends the rest of the section discussing a inheritance via meiosis and mitosis. That's it. The biggest revolution in evolutionary theory swept under the rug in one brief paragraph.

IMO, the second biggest change in evolutionary theory, since the 1930s is the revolution represented by symbiology. This conclusively added merging and joining operations to the basic evolutionary toolkit - which had previously consisted of splitting and selection. Surely any discussion of updating the modern synthesis ought to include some coverage of this change to the basic fundamentals of evolutionary theory. Futuyma gives this revolution one sentence. He writes: "possibly newly established endosymbioses will likewise have large but beneficial effects".

Since Futuyma offers so little coverage of what I consider to be the real revolutions in evolutionary theory since the 1930s, what does he talk about? S. J. Gould is mentioned 45 times in the essay. Alas, my rather dim view of S. J. Gould extends to those who take him seriously. I'm mostly OK with bashing Gould's proposed revolutions, but here they are distracting from the real action - and that's not OK.

The essay closes with the comment:

Of course, the Evolutionary Synthesis will be extended, molded, and modified. But there will not be a Kuhnian “paradigm shift.”
My take on the "paradigm shift" business is a bit different. Evolutionary theory caused a pretty dramatic shift in biology in the 1800s. It causes similarly dramatic shifts in other fields it enters. Evolutionary economics is a major shift for economics, evolutionary epistemology is a major shift for epistemology - and so on. What Futuyma is apparently talking about is a paradigm shift within evolutionary theory. Most of the claims for memetics as a paradigm shift aren't talking about that. For example, Richard Brodie, in Virus of the Mind (1996), says:

Viruses of the mind, and the whole science of memetics, represent a major paradigm shift in the science of the mind.

In Thought Contagion, Aaron Lynch (1998) wrote:

Memetics represents just such a paradigm shift. In a nutshell, it takes the much explored question of how people acquire ideas, and turns it on its head - the new approach asks how ideas acquire people.

These folks are talking about memetics as a paradigm shift within psychology.

Are memetics and universal Darwinism a paradigm shift within evolutionary theory? This raises the issue of what qualifies. I have described symbiology and the expansion of evolutionary theory's domain as being 'revolutions'. However, they clearly build on the existing theory. A "Kuhnian paradigm shift" doesn't seem to be a particularly well-defined scientific concept, so it is not always easy to see whether something qualifies or not. Ultimately it doesn't matter. What's more important is to digest and assimilate the revolutions. At this stage, I'm not convinced that Futuyma has done very much of that.

Does Futuyma have any understanding of cultural evolution? If there was evidence that he knew what he was talking about, I might give his opinion some more weight. It's hard to coherently argue against the significance of a scientific revolution when you don't even understand it.

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