Why is sex fun- Jared Diamond

Why is Sex Fun? reads like a lecture series rather than a book. Apparently intended to provide the reader with an overview of the latest thinking on the evolutionary aspects of the subject, this short work includes sections on different sexual (and mate) selection strategies employed by males and females (presumably based on unequal "investments" in the methods of getting one's genes into the next generation); lactation (why milk is produced by females, but not, as a rule, males); how and why humans, almost uniquely, came to engage in engage in recreational sex; the unequal domestic roles played by males and females, particularly in child rearing; female menopause (which is, again, nearly unique to humans); and sexual signaling (Diamond considers penis length in human males to be a prime example, but not necessarily a signal directed at females).

The Third Chimpanzee: The Evolution and Future of the Human Animal

We human beings share 98 percent of our genes with chimpanzees. Yet humans are the dominant species on the planet -- having founded civilizations and religions, developed intricate and diverse forms of communication, learned science, built cities, and created breathtaking works of art -- while chimps remain animals concerned primarily with the basic necessities of survival. What is it about that two percent difference in DNA that has created such a divergence between evolutionary cousins? In this fascinating, provocative, passionate, funny, endlessly entertaining work, renowned Pulitzer Prize–winning author and scientist Jared Diamond explores how the extraordinary human animal, in a remarkably short time, developed the capacity to rule the world . . . and the means to irrevocably destroy it.

Jared Diamond states the theme of his book up-front: "How the human species changed, within a short time, from just another species of big mammal to a world conqueror; and how we acquired the capacity to reverse all that progress overnight." The Third Chimpanzee is, in many ways, a prequel to Diamond's prize-winning Guns, Germs, and Steel. While Guns examines "the fates of human societies," this work surveys the longer sweep of human evolution, from our origin as just another chimpanzee a few million years ago. Diamond writes:

It's obvious that humans are unlike all animals. It's also obvious that we're a species of big mammal down to the minutest details of our anatomy and our molecules. That contradiction is the most fascinating feature of the human species.