+In this way (contrary to the uninformed suspicions of those still faithful to the blank slate), evolutionary psychology actually turns out to be impressively antiracist discipline: maybe individual humans can differ in small ways like personality, or ancestry-groups in small ways like skin color, but these are, and _have_ to be, "shallow" low-complexity variations on the same basic human design; new _complex_ functionality would require speciation.
+
+This luck does not extend to antisexism. If the genome were a computer program, it would have `if female { /* ... */ } else if male { /* ... */ }` conditional blocks, and inside those blocks, you can have complex sex-specific functionality. By default, selection pressures on one sex tend to drag the other along for the ride—men have nipples because there's no particular reason for them not to—but in those cases where it was advantageous in the environment of evolutionary adaptedness for females and males to do things _differently_, sexual dimorphism can evolve (slowly—[more than one and half orders of magnitude slower than monomorphic adaptations](/papers/rogers-mukherjee-quantitative_genetics_of_sexual_dimorphism.pdf), in fact).
+
+The evolutionary theorist Robert Trivers wrote, "One can, in effect, treat the sexes as if they were different species, the opposite sex being a resource relevant to producing maximum surviving offspring" (!!). There actually isn't one species-universal design—it's _two_ designs.
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+If you're willing to admit to the possibility of psychological sex differences _at all_, you have to admit that sex differences in the parts of the mind that are _specifically about mating_ are going to be a prime candidate. (But by no means the only one—different means of reproductive have different implications for [life-history strategies](https://en.wikipedia.org/wiki/Life_history_theory) far beyond the act of mating itself.) Even if there's a lot of "shared code" in how love-and-attachment works in general, there are also going to be specific differences that were [optimized for](https://www.lesswrong.com/posts/8vpf46nLMDYPC6wA4/optimization-and-the-intelligence-explosion) facilitating males impregnating females. In that sense, the claim that "the love of a man for a woman, and the love of a woman for a man, have not been cognitively derived from each other" just seems commonsensically _true_.