Thursday, 22 December 2011

Tim Tyler: Sense and Nonsense (review)


Hi! I'm Tim Tyler and this is a video review of Sense and Nonsense by Laland and Brown.

Sense and Nonsense is a great book. It covers a range of evolutionary approaches to human behaviour. The key concepts of each approach are treated in turn in separate chapters and then the authors describe case studies and then offer a critical evaluation for each one.

The approaches considered are: sociobiology, human behavioural ecology, evolutionary psychology, memetics and gene-culture coevolution.

There's also an introductory chapter, a chapter covering the history of the field prior to 1975 and a final chapter that wraps up.

I read the last three chapters first. These are the ones on memetics, gene-culture coevolution and the last chapter on "comparing and integrating approaches". I did this because Memetics and gene-culture coevolution are really the only remaining attempts at a proper study of human evolution, and that matches my own particular interests.

The authors are mostly in the "gene-culture coevolution" camp. They seem to be mostly looking at the other approaches to see where they went wrong. Their descriptions of the other approaches are pretty fair, but they do go out of their way sometimes to make then look stupid.

Despite this, their coverage of memetics is mostly accurate, sympathetic and good. However, the authors do say:

Perhaps because of the need to demonstrate that culture is a genuine evolutionary process in its own right and cannot be reduced to a mere product of biological evolution, so far meme enthusiasts have concentrated almost exclusively on the characteristics that make memes infectious. However, the success of a virus depends not only on its infectiousness but also on the susceptibility of its hosts and on whether the social environment promotes contact between hosts. The same three factors may also determine the success of memes (Laland and Odling-Smee, 2000). Were memeticists to accept that evolved genetic predispositions may influence meme adoption, leaving human beings particularly susceptible to acquiring memes that increase their reproductive success, they would converge on the ideological position of advocates of gene–culture coevolution.
This seems strange to me. I checked with Blackmore's meme book - published three years before "Sense and Nonsense" - and she has a section about how meme transmission depends on both properties of the memes and properties of their hosts on page 15.

Aaron Lynch's 1996 book talks about "cognitive immune reactions" against memes, the idea of a "memetic immune mechanism".

The idea that memetics doesn't have this covered seems to me to be patronising nonsense.

The authors claim that memetics:

denies any substantive filtering role for evolved psychological mechanisms.
I am very sceptical. I've never come across any author who has said anything remotely like that. I suspect this is down to some kind of misunderstanding.

The next chapter is about gene-culture coevolution. I found some oddities there as well. The book says:

Social transmission can occur vertically (that is, from parents to offspring), obliquely (from the parental to the offspring generation; for instance, learning from teachers or religious elders) or horizontally (that is within-generation transmission, such as learning from friends or siblings). Of course, genetic inheritance is exclusively vertical and hence, as social transmission frequently occurs through some combination of these modes of information transmission, cultural evolution and gene–culture coevolution may commonly exhibit quite different properties from biological evolution.
However, this is completely untrue. Organic entities can be transmitted down the generations horizontally and obliquely too. This happens with parasites and mutualists. This is in fact a deep similarity between organic and cultural evolution - rather than grounds for treating them differently.

I felt the authors were rather soft on Boyd and Richerson's Cultural Group Selection concept. They say:

Boyd and Richerson propose an alternative form of group selection that just might work.
...and then use the concept to support the thesis that:
Their analysis demonstrates that, when cultural transmission is included into evolutionary models, the nature of the evolutionary process may be quite dramaticallly different.
However, this is not a very reasonable conclusion. Parasites also act so as to rapidly produce and maintain differences between groups of humans. Parasites have very similar dynamics to culture in this respect. Like culture, they involve horizontal spread between hosts, short lifecycles and rapid evolution. As with culture, migrants tend to adopt the parasites of their new population. We have empirical data on the relative influence of parasites and culture when it comes to death as a result of humans invading other groups of humans - since there have been many invasions in recorded history - for example in America, Australia and Africa. Organic parasites (such as smallpox) did a large proportion of the work in producing fitness differences between groups of humans in many of the cases studied - accounting for more than half the deaths in some cases. Culture does some of this work too - but the organic and cultural realms are not so different here.

There are some differences between organic and cultural evolutionary change - but Cultural Group Selection seems to be a poor example of such a difference - since parasites and mutualists in the organic world behave so similarly.

Next, th chapter on evolutionary psychology. This chapter is excellent. I especially appreciated the idea that the popularity of evolutionary psychology is partly due to its manifest lack of racism. However, the authors don't mention the biggest criticism of evolutionary psychology until the very end of their chapter. That criticism is that - as currently practiced - evolutionary psychology only deals with human universals and says little about cultural evolution. I feel that this point needs to be emphasised at least a little. While evolutionary psychology only deals with human universals it will remain a folorn and useless endeavour. Culture is just too important a force to ignore. Ignoring it has produced a substantial mountain of evolutionary psychology-based junk science. To become relevant, evolutionary psychology must reform itself - or attempt to fuse with memetics and/or gene-culture coevolution.

The chapter on human behavioural ecology is again of fine quality. However, human behavioural ecology isn't really a seriopus attempt to model human evolution. It is a small piece of the puzzle.

The chapter on sociobiology was excellent as well. Controversy makes for readability, and this chapter was quite a page-turner. Sociobiology was a nice idea but it became rather tarred by association with Wilson's presentation of it - which had both theoretical and political shortcomings. Wilson went on to try and fuse sociobiology with his own version of gene-culture coevolution - an attempt which met with only rather limited success. These days sociobiology seems to have mostly become a dirty word - which is a bit of a shame.

Lastly the history chapter. This covers Charles Darwin, Herbert Spencer, Jean Baptiste de Lamarck, Francis Galton, Konrad Lorenz, Desmond Morris - and many others. I thought this was the worst chapter in the book - and recommend readers read it last - so they are not put off. One of the chapter's themes is that people believed in progressive evolution - which led to all manner of social evils - whereas now we know that evolution has no direction. However, progressive evolution is a perfectly reasonable concept, and it is clearly evident in the world. The authors apparently criticise it without even trying very hard to understand it. Social evolution is a politically-charged subject. I appreciate that it is hard to cover the subject objectively - but I felt that the authors failed to keep their own political perspective out of the picture.

The book has dated rather little in the 10 years since 2002 - though I believe the work has been republished recently. Gene-culture coevolution is now on a much firmer footing. The author's call for more experimental work has been met in the mean time with a substantial volume of work demonstrating cultural evolution under laboratory conditions, and probing the properties of cultural transmission processes.

The authors manage to make themselves look pretty smart in the book, by poking holes in practically all the existing theories. That is not unreasonable - the authors are obviously pretty smart people - but I found it a little grating. From time to time, I noticed that the criticised theories were getting bent out of shape a little - in ways which helped to give the authors some corrective work to do.

The book is very broad and ambitious in scope. Alas, that means it inevitably lacks depth. I would have much preferred a book about the topic covered in the last three chapters. Having said that, several of the other chapters were mostly high-quality entertaining content containing material which I was less familiar with - so I learned more from them.

Anyway, overall a great book, I expect that most readers will learn a considerable amount of interesting things about how evolution applies and has been applied to humans from it.


No comments:

Post a Comment