Sunday, 17 March 2013

Tim Tyler: Wilson, The Social Conquest of Earth (review)


Hi. I'm Tim Tyler, and this is a review of this book:

The Social Conquest of Earth by Edward O. Wilson
The book is about the rise of social organisms on the planet and how they have come to dominate their ecosystems. Wilson uses ants and humans as his main examples of the success of sociality.

It's aiming to be a popular book. There are, in fact, a few scientific references in the book, but if you're not careful, you won't find them until you get to the very end - where they are clustered together in a list.

The first 100 pages of the book is a history of the rise of humans. Alas, I'm one of those who often finds histories boring, so I had to push a bit through this section of the book. Then there's thirty pages on social insects. Then there's sixty pages on the theories of social evolution. This is really where Wilson comes unstuck.

Wilson launches into a misguided attack on kin selection theory. Obviously, Wilson has some understanding of kin selection. However, he doesn't have a sympathetic understanding of it, and instead seeks to destroy and discredit it. Alas, in order to do this, he has to set up a series of straw men and then vigorously attack them. This might be entertaining for some - but Wilson is a popular author, and here we run the risk of an eminent scientist confusing and misleading the next generation of students. About the best that can be said for Wilson's attack on kin selection is that it is embarrassing and half-baked. I noticed that, as if to illustrate that he doesn't really know what he is talking about, Wilson gives an incorrect definition of inclusive fitness, saying:

The inclusive fitness of the individual is its personal fitness, in other words the number of its personal offspring who grow up and have children of their own added to the effect its actions will have on the fitness of its collateral relatives, such as siblings, aunts, uncles, and cousins.

That definition is wrong. Those familiar with the topic will recognise that it's only two thirds of the correct definition. Wilson goes on to discuss the claimed equivalence of kin and group selection. He says:

Further there are mathematical difficulties with the definition of r, the degree of relatedness. These difficulties render incorrect the oft-repeated claim that group selection is the same as kin selection expressed through inclusive fitness.
After supposedly demolishing the decades of work by kin selection theorists, Wilson goes on to present his preferred alternative theory of social evolution - which is based on group selection and the idea of group-forming forces - where Wilson gives a "defensible nest" as his main example of the latter.

Unfortunately, Wilson's book is probably exhibit number one when it comes to showing how group selection leads to confusion about evolutionary theory. Wilson is evidently in a hopeless muddle about kin selection and group selection. It seems hard to avoid the conclusion that group selection lies at the root of the problem. While Wilson might have been trying to help the cause of group selection in his book, it seems more likely that it will be an embarrassment for group selection's proponents.

Group selection's main problem that it faces a well-armed opponent. Kin selection explains all the same things that group selection explains - and has been scientific orthodoxy for decades. Most modern group selection enthusiasts seem to have finally agreed that group selection makes no predictions not also made by kin selection. The main case for group selection these days seems to amount to the idea that it represents a stimulating alternative perspective. High-level selection can be a form of holism to counter kin selection's reductionism. Group selection models can be tractable in some cases where lower-level kin selection models are not. This is all reasonable: group selection does have a positive side. The problem with group selection is that historically its use has often led to junk science. People tend to invoke benefits to group willy-nilly - without doing the math, or even sanity-checking their explanations. To many scientists, group selection explanations thus often look like a poor substitute for actually understanding what is going on. Many explanations based on group selection, on closer examination, have turned out to be wrong or misleading. In the cases group selection is useful, kin selection is often more useful. SO, group selection has its merits - but needs a health warning.

Wilson claims that humans are a eusocial species - even though we mostly lack one of the primary traits associated with eusociality - namely reproductive division of labour. Wilson doesn't explain that his use of the term is unorthodox and controversial.

Wilson's examples of eusociality are all from animals. He lists beetles, aphids, thrips, shrimps, mole rats and humans. However there are other examples of social behaviour among microbes, plants and fungi. In particular multicellularity is a common form of eusociality. The examples of its evolution illuminate the topic of social evolution. However, Wilson makes no use of these examples.

Wilson attempts to apply the study of animal social evolution to humans - and this leads him to the kin selection (or group selection) axis. While important, this leads to a pretty myopic perspective on human social behaviour, which is heavily influenced by reciprocity, reputations, byproduct mutualism - and manipulation of humans by memes. You can't really coherently discuss human social evolution without casting your net wider than this.

Lastly, the book ends up with a review of cultural evolution in humans. In the 1980s Wilson was a pioneer in applying biology to human culturally-transmitted behaviour, writing two books on this topic. Wilson at least understands that culture evolves - and that memes coevolve with genes. However, his older books promoted a pre-memetics perspective, in which everything boiled down to DNA genes. Checking to see if Wilson had moved on 40 years later, I was surprised to find that little had changed. He cited his old work, and trotted out much the same theory that he advocated back in the 1980s. This idea has been totally superseded in the mean time by the application of Darwinian evolutionary theory directly to cultural variation - along the lines pioneered by Richard Dawkins in 1976. Wilson's discussion of this work is confined to one paragraph. He chastises the researchers involved for paying insufficient attention to the interactions between genes and memes - and then launches into a laundry list of such interactions.

This hopeless treatment of cultural evolution might not matter - but this is one of the few books addressing the topic that I regularly see in bookshops. This might be the first exposure to the topic for many. A teaching opportunity has been squandered, because Wilson is stuck back in the 1970s on the topic and has failed to grok most of the more recent literature.

In the book, Wilson expands on his old claim that genes keep memes on a leash by presenting an argument against the possibility of a memetic takeover. He says:

I am further inclined to discount the widespread belief that robotic intelligence will overtake and potentially replace human intelligence.

What are Wilson's reasons? He goes on to give them, saying:

To advance from robot to human would be a task of immense technological difficulty. But why should we even wish to try? Even after our machines far exceed our outer mental capacities, they will not have anything resembling human minds. In any case, we do not need such robots, and we will not want them. The biological human mind is our province.

Wilson's objection seems simple-minded to me. He gives me no reason to think that he knows much about machine intelligence or futurism. He's just a famous biologist speculating on something about which he knows little. The idea that people will lack motivation to build superhuman intelligent machines just seems daft to me. The motivation is obvious.

So: this is not a good book. It is quite readable, but it's full of outdated or wrong science. Readers should be warned that, while Wilson speaks authoritatively, he doesn't really know what he's talking about in many places.


No comments:

Post a Comment