Steven Pinker -- How the Mind Works - Hampshire High Italian ...

Revenge of the Nerds 205related at all! Similarly, the birthday of humanity's most recent commonall-female-line ancestor, mitochondrial Eve, overestimates how long agoall of humanity was still interbreeding.Well after Eve's day, some geneticists think, our ancestors passedthrough a population bottleneck. According to their scenario, which isbased on the remarkable sameness of genes across modern human populations,around 65,000 years ago our ancestors dwindled to a mere tenthousand people, perhaps because of a global cooling triggered by a volcanoin Sumatra. The human race was as endangered as mountain gorillasare today. The population then exploded in Africa and spun off smallbands that moved to other corners of the world, possibly mating now andagain with other early humans in their path. Many geneticists believethat evolution is especially rapid when scattered populations exchangeoccasional migrants. Natural selection can quickly adapt each group tolocal conditions, so one or more can cope with any new challenge thatarises, and their handy genes will then be imported by the neighbors.Perhaps this period saw a final flowering in the evolution of the humanmind. 0All reconstructions of our evolutionary history are controversial, andthe conventional wisdom changes monthly. But I predict that the closingdate of our biological evolution will creep later, and the opening date ofthe archeological revolution will creep earlier, until they coincide. Ourminds and our way of life evolved together.WHAT NOW?Are we still evolving? Biologically, probably not much. Evolution has nomomentum, so we will not turn into the creepy bloat-heads of sciencefiction. The modern human condition is not conducive to real evolutioneither. We infest the whole habitable and not-so-habitable earth, migrateat will, and zigzag from lifestyle to lifestyle. This makes us a nebulous,moving target for natural selection. If the species is evolving at all, it ishappening too slowly and unpredictably for us to know the direction.But Victorian hopes spring eternal. If genuine natural selection cannotimprove us, maybe a human-made substitute can. The social sciences arefilled with claims that new kinds of adaptation and selection haveextended the biological kind. But the claims, I think, are misleading.