Matt Ridley's The Red Queen

In The Red Queen, Matt Ridley  provides an excellent introduction to the evolution of sex.  While "Sex and the Evolution of Human Nature" is eventually delivered, in fact he starts at a more basic level - why does sex exist at all?

He begins with the simplest of single-celled organisms - indeed, with their predecessors - to show why gene swapping is useful.  He looks at parasites as a driver of evolution and a promoter of genetic diversity in a population, and how "the tragedy of the commons" is a good analogy for why species with sexes generally (but not quite universally) settle on two.

Throughout the book, there are fascinating details of biology that I had not been exposed to before - like the chromosomal system in lemmings which ensures that there are three females for every male.

Much of the book looks at the behavior of birds - Ridley considers bird mating behavior, which in many species consists of "monogamy with cheating" a fair match for human behavior.

When the book moves on to cover human nature, much attention is also given to our closest relatives.  I now have a fair better understanding of why gibbons are monogamous and chimpanzies are not, for example.  He also presents reasonably convincing arguments for the relative occurrence of polygamy and monogamy (and the near total absence of polyandry) among humans.  

Throughout the book, Ridley reveals science as a human endeavor.  Scientists are names and their theories are examined in context.  Where there is no clear consensus between contending theories  as of yet, the contending arguments are laid out and there is no pretext that "Science knows the truth".  For a reader interested in real science and not just in a collection of "facts" this is invaluable.

The final chapters, which look at asymmetries between male and female human brains and at contending theories of cultural rather than biological origins for modern human behavior, Ridley is well aware he is entering contentious ground.  His arguments are convincing, but he does not pretend that they are the only ones available.

Published in 1993, the book may be mildly dated on matters of biochemical detail but not to an extend that would affect his arguments.  It is entertaining and well worth reading.