From Why We Bite the Invisible Hand by Peter Foster
That species could be deliberately modified was clear from the selective breeding of dogs and other animals, as well as plants, that had been carried on for thousands of years. Promise of an evolutionary theory was also seen in common embryonic forms of many species. There were also vestigial features, such as male nipples, which suggest a biological purpose made redundant over time. To these observations were added, thanks to Darwin’s travels, questions about the geographical distribution of, and environmental influence on, species: that is, how similar species appeared in similar environments in far distant parts of the world.
Darwin spent more than twenty years mulling over these issues in the bucolic surroundings of his Kent estate, going for thrice-daily walks along his “thinking path.” Then in 1859, he was shocked when another naturalist, the self-taught Alfred Russel Wallace, sent him a letter outlining a theory almost identical to his own. Darwin was forced to produce The Origin of the Species in a relatively short time, and to present it beside that of Wallace, who generously deferred to Darwin’s superior scientific status.
Darwin’s theory of natural selection states that life forms evolve–and split into different species–by a process of mutation between generations. Those mutations that make a life form more “fit” to survive and procreate within its relevant environment are more likely to be passed on, further mutated, tested once more for fitness and on and on. The creation of new species occurs when life forms branch off via mutation and can no longer interbreed with those on the home branch. Darwin noted how, in such a process of evolution and speciation, the natural selection of adaptive random variations could give the appearance of intentional design.
Genes, as we now know, carry the design specification for living creatures. Genes split during reproduction. Mutation comes via “transcription error.” Most mutations are maladaptive, but occasionally one increases its organism’s chance of reproduction. Hence, “useful” adaptions–which marginally increase speed or strength or reaction times or smell or eyesight, or any of a multiplicity of interrelated characteristics or tendencies–are more likely to be passed on.
The notion of an evolved–and thus limited and potentially biased–mind tends to be inconceivable. Alfred Russel Wallace, for example, couldn’t bring himself to countenance the mind as merely a function of an evolved organ. To ask what kind of thing the mind is, we start by asking how, and in response to what challenges, it evolved. Our mental apparatus evolved to help us survive in our immediate environment, but it wasn’t just a physical world of colours, odours, shapes, distances, masses, velocities, trajectories, poisons and predators; it was also a social world. Man formed society, and society formed man. The key issue was the nature of that chicken-and-egg relationship.
Our minds–defined as what our brains do–developed along with, and as a computing and guiding mechanism for, our physical and social interactions. The key insight of evolutionary psychology is that as much as 99% of that evolution may have taken place while we were hunter-gatherers. Thus our brains and minds were overwhelmingly formed when we lived in small, closely related tribal groups, whose existence revolved around hunting, food gathering, sex, fighting, and “local politics.”
There is a huge and growing literature on humans’ often unconscious sexual attitudes, preferences and strategies, and how they differ between men and women. For example, males tend to be more concerned about sexual infidelity, women about emotional infidelity. That’s because it’s more adaptive for males to be concerned with paternity (whether a child is likely to have their genes), while women tend to be more concerned about male “commitment,” which goes with protection and access to resources for their children (whether those children are the progeny of the committed man or not).
The fact that contraceptive technology has made men’s jealousy “rationally” redundant doesn’t make much difference to our moral sentiments. As journalist Robert Wright wryly points out in his book The Moral Animal, “For the average husband, the fact that his wife inserted a diaphragm before copulating with her tennis instructor will not be a major source of consolation.” Similarly, Ayn Rand’s reaction to Nathaniel Branden’s emotional desertion was certainly not related to any concerns that he wasn’t going to be around to look after the babies she was never going to have. Both these examples indicate how emotions evolved to serve genetically “rational” ends, while driving us, their vehicles, crazy.