"The distinction between central and peripheral claims is applicable to many aspects of human sexuality. Consider, for instance, the emotion of jealousy. Evolutionary psychologists place a strong emphasis on sex differences in this domain. The standard claim is that men are more worried by a partner’s sexual infidelity than emotional infidelity, whereas women are more worried by a partner’s emotional infidelity... the overwhelming trend is that most men and most women are extremely upset by both sexual and emotional infidelity. This suggests that the central EP claim regarding jealousy should be “Human beings evolved to experience jealousy in romantic relationships” rather than “Men and women evolved different patterns of jealousy.” The latter statement is true but should be considered a qualification to the former: a peripheral rather than a central claim. To stress the sex difference alone would be like observing that male elephants are bigger than females while steadfastly neglecting to mention that all adult elephants are large compared to most terrestrial animals. It would almost certainly foster an inaccurate view."

“From a comparative perspective, we are a relatively monomorphic mammal, with relatively monomorphic minds.”

“The idea that women are the choosier sex is one of the best-known claims associated with EP . Ironically, another of the best-known claims associated with EP is an exception to this rule: On average, men are choosier than women when it comes to the physical attractiveness of a prospective mate. Even if we put this counterexample aside, though, the statement “females are choosier than males,” although true of many species, does not apply easily to our own. It is true that men may sometimes be more willing than women to lower their standards for a casual sexual partner. However, when it comes to the most important mating decisions of a man’s life — who he will marry, who he will have children with — the difference in choosiness is much smaller and maybe nonexistent. This fact of human life is even implicit in everyday folk psychology; the stereotype is that men will “sleep with anything that moves,” not that they will marry or have children with anything that moves. In long-term, committed relationships, men are about as choosy as women.”

“Changes in the inhabitants of the earth do not reflect a constant process of improvement in the design of organisms, any more than changes in fashion over the years reflect a constant process of improvement in the quality of clothing.”

“One could even argue that our creative endeavours and achievements and small acts of kindness are all the more impressive against the backdrop of a purposeless universe.”

“We like to think that reason is the supreme adaptation; that rational animals deserve preferential treatment; and that nonhumans, because they don’t have reason, have no intrinsic moral value. However, after Darwin, this is no different and no more convincing than, say, an elephant thinking that trunks are the supreme adaptation; that animals with trunks deserve preferential treatment; and that non-elephants, because they don’t have trunks, have no intrinsic moral value.”

“Of course, nothing can be said to argue that people are morally obliged to accept this ethic, for to do so would be inconsistent with the ideas that inspired it in the first place. It is an ethic that will be adopted – if at all – by those who find a certain stark beauty in kindness without reward, joy without purpose, and progress without lasting achievement.”