Anant Jain

The Selfish Gene

Book Review

I heard this one as an audiobook — which means I probably retained a lot less than I otherwise would have. I forewarn that parts of this book might be a little controversial or hard to swallow, but I remember coming out severely impressed by the elegance of the Selfish Gene theory. Overall, it’s a very interesting read and you shouldn’t miss it.

The Selfish Gene

In this anthropomorphized interpretation of the gene, it’s pretty clear that genes themselves are not “selfish” — after all, how can they be? They are molecules that have no motives or will! The metaphor of selfishness implies that their effects can be interpreted as if they were — genes that are passed on are the ones whose evolutionary consequences serve their own implicit, selfish interests in being replicated, and not necessarily of the organism replicating them. They are passed over thousands of generations over millenia, and the organism is just a carrier for the selfish gene.

To be precise, the genes are the fundamental units of natural selection that form lineages of identical copies with occasional random mutations. We will call them the ‘replicators’. They generally gang together into large communal survival machines — the organisms or as we will call them, the ‘vehicles’.

More often than not, genes that succeed provide a benefit to the organism. A gene that prevents a disease helps the organism survive long enough to pass it onto its offsprings, which is great both for the organism and the gene. At times, the interests of the gene might be at odds with the interests of the organism: menopause prevents women from having more offsprings of their own after a certain age, which could be against the individual’s interests, but it ensures the gene’s survival:

Researchers who studied population records from Finland before the Industrial Revolution found that children were more likely to survive till adulthood if their grandmothers were still alive. Menopause might therefore be a winning evolutionary strategy because it leads to more grandchildren who can carry on Grandma’s genes.

Hence the selfish gene that causes menopause gets propagated.

Group Selection vs. Individual Selection

Although Dawkins is not in direct opposition with Darwin’s theory of Natural Selection, he feels that Darwin’s ideas have largely been misinterpreted. The Selfish Gene theory suggests that Individual Selection is far more common than selection based on groups or populations. To quote Dawkins again:

The organism and the group of organisms are true rivals for the vehicle role in the story, but neither of them is even a candidate for the replicator role. The controversy between ‘individual selection’ and ‘group selection’ is a controversy between alternative vehicles.

Thus, it’s the selfish gene, or the replicator, that selects itself for propagation. The debate on what vehicle it uses to do so is mostly irrelevant.

Evolutionary Stable Strategies

I also liked Dawkins’ treatment of various scenarios by trying to work out what he calls an Evolutionary Stable Strategy: a strategy which if adopted by all members of a population cannot be invaded by a mutant strategy through the operation of natural selection. A great analogy to go through was the Iterated Prisoner’s Dilemma, and how Tit-for-Tat coulde be an ESS in this case. But that’s a post of its own. The book is full of analyses on how various startegies could or could not be evolutionary stable in the face of mutant gene that competes with it. Paradoxically, in most of the cases, we find that the selfish gene makes us act more altruistic since it’s only in its benefit to do so. Nice guys finish first. (Edit: I found this amazing game on Iterated Prisoner’s Dilemma that you should check out: http://ncase.me/trust/)

Battle of the Sexes

This was the most controversial part of the book for me. Dawkins theorizes that at some point, all sex cells (known as gametes) were the same size. Due to a mutation, one group probably began to develop larger sex cells since the larger endowment of resources would lead to a better survival rate for their offsprings. This group was ripe for exploitation, and the other group started making a larger number of smaller, more mobile sex cells to reach the larger sex cells. Hence the two major sexes were born.

This is where the inequality begins.

The fundamental inequality that starts off with the females being a lot more invested in the child after conception can explain why we have so many single mothers in our society. The investment for males is lower, and hence are more likely to not invest resources in their offspring, since they can go and create more with someone else. So how does the woman get the man to stick around and raise the child? One strategy is to court the male for a long time before allowing him to mate in order to increase his investment. They can also make him invest a certain amount of resources before being allowed to mate — an example of this is making the male build a nest. I know this topic is quite murky, but it’s not you, it’s our selfish genes.

Memes as genes

The tail end of the book draws parallels between spread of memes and the propagation of genes. Both are replicators that use vehicles to spread themselves. The memes are passed on from one brain to another via writing, gestures, and speech. Memes are like genes in that they replicate and are responsive to pressures of selection. They spread through the behavior of the hosts in whom they reside, and those that replicate less than others can become extinct. This section reminded me of the Contagious book by Jonah Berger which I read a few years ago: it talks about how ideas that provide social currency, are easily triggered, emotional, public, of practical value and packaged as stories spread the most.¹

Conclusion

As Dawkins puts it:

We are survival machines — robot vehicles blindly programmed to preserve the selfish molecules known as genes. This is a truth which still fills me with astonishment. Though I have known it for years, I never seem to get fully used to it. One of my hopes is that I may have some success in astonishing others.

Very riveting, go read it.


[1] This might be my first one-line summary of a book. 😀

This is #7 in a series of book reviews published weekly on this site.

So Selfish, eh!