River out of Eden

Richard Dawkins gives a very readable account, as ever, of some rather abstract issues within evolutionary biology.

How we are all much more closely related to each other than some might care to think. The river of the title is the mitocondrial DNA that flows through teh generations on the maternal side.

How evolution actually works, how it has no purpose and doesn't necessarily select the 'best' organisms, just the best in the environment at the time (on average). In esscence how a blind, simple process of random mutation combined with selective reproduction can explain the wonderful diversity of life we see around us today.