Finally finished this one. Nowhere near as interesting as The Voyage of the Beagle or The Origin of Species. There are a few reasons for this, such as the fact that so much more has been discovered about human descent since the book was written. Also, half of it is comprised of extensive evidence for sexual selection in evolution, something that I already know exists - I don't need to read hundreds of pages of examples about this. Still, some of the examples are interesting.