As Donald Symons (1985) puts it, “in analyzing the psychologicalunderpinning of marriage [we should] keep in mind that
Homo sapiens
is the product of evolution by natural selection; we are designed to promote gene, not individual, survival;reproductive, not marital success” (p. 152).
Insofar as we have inherited the anatomical, biological, andpsychological architecture of our forebears, we have a hard-wired desire for a (limited)form of primary-partner commitment as well as a powerful, sex-lopsided urge for extra-pair copulation over the life course
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(see Symons 1987, 1992; Tooby and Cosmides1992; Buss 1994; Barash and Lipton 1997).