Asked by: Ray Jeffrey, by email
Evolution operates over timescales of millions of years. Our ability to alter birth rates and survival chances, through technology and medicine, is so powerful that it swamps the gentle tug of natural selection. Genetic engineering, cosmetic surgery and prosthetic implants will eventually reach the point where the shape of our bodies is as much a matter of fashion as the clothes we wear. And just like hemlines, there’s no final goal with this process, or even a single ideal. Humans will sculpt themselves according to changing ideas of aesthetic beauty. Thin and tanned may give way to pale and plump, then short and hairy, then back to thin. Much of this won’t be heritable change any more than making our children wear braces to straighten their teeth affects the genes they pass on to their children.