Humanity shares this profile of ardent, polygamist males and coy, faithful females with about 99 percent of all animal species, including our closest… - Matt Ridley

Parasites invent new keys; hosts change the locks. There is an obvious group-selectionist argument here for sex: At any one time a sexual species will have lots of different locks; members of an asexual one will all have the same locks. So the parasite with the right key will quickly exterminate the asexual species but not the sexual one. Hence the well-known fact: By turning our fields over to monocultures of increasingly inbred strains of wheat and maize, we are inviting the very epidemics of disease that can only be fought by the pesticides we are forced to use in ever larger quantities.

As you grow up, you gradually express your own innate intelligence and leave behind the influences stamped on you by others. You select the environments that suit your innate tendencies, rather than adjusting your innate tendencies to the environments you find yourself in. This proves two vital things: that genetic influences are not frozen at conception and that environmental influences are not inexorably cumulative. Heritability does not mean immutability.

Life is a slippery thing to define, but it consists of two very different skills: the ability to replicate, and the ability to create order.