Our genomes reveal modern-day evolution

摘要

WE ARE still evolving - very slowly. In the 20th century, people in the UK evolved to be less likely to smoke heavily, but the effect was tiny. So claims a study of 200,000 genomes. A population can be described as evolving when the frequency of gene variants changes over time. Because most people in rich countries now live well beyond reproductive age, some argue that we have stopped evolving because natural selection has been weakened. But several recent studies claim we are still evolving, albeit slowly.