In such condition, there is no place for industry; because the fruit thereof is uncertain: and consequently no culture of the earth; no navigation, nor use of the commodities that may be imported by sea; no commodious building; no instruments of moving, and removing, such things as require much force; no knowledge of the face of the earth; no account of time; no arts; no letters; no society; and which is worst of all, continual fear, and danger of violent death; and the life of man, solitary, poor, nasty, brutish, and short. — "Chapter XIII.: Of the Natural Condition of Mankind As Concerning Their Felicity, and Misery.", Leviathan, Thomas Hobbes
Not only has natural selection not stopped since the advent of civilization, it has changed in subtle ways.
The Scientist: In 1974, the UK Medical Research Council (MRC) set up clinics in two rural villages in Gambia’s West Kiang district, offering free medical care to locals. The effect was dramatic. Thanks to good health care, better infrastructure, and accessible contraception, the villagers started living longer and having fewer children.
Over a short time, the district went through a modern-day demographic transition—a well-known fall in birth and death rates typically seen when human societies move to industrialized economies—causing natural selection to act upon the population in noticeably altered ways, according to a study published today (April 25) in Current Biology.
Alexandre Courtiol from the Leibniz Institute for Zoo and Wildlife Research and Ian Rickard from Durham University found that before 1974, shorter, fatter women had the highest relative fitness—measured by the number of descendants they leave behind. But since the clinic was built, selection pressures have flip-flopped so that taller, thinner women now have the advantage.
Their results are the latest to challenge the idea that modern humans have stopped evolving due to industrialization and medical advances. Although the team did not find any actual changes in gene frequencies—the gold standard for demonstrating evolution has taken place—“the paper illustrates that natural selection persists in contemporary human populations,” said Jacob Moorad, an evolutionary biologist from Duke University who was not involved in the study. “And this force for evolutionary change is fluid.” ...