BEIJING, July 22 (UPI) -- Humans may have made significant evolutionary changes much more recently than previously thought, as little as 3,000 years ago, researchers say.
Scientists from the Beijing Genomics Institute found among Tibetans a set of genes showing they evolved to deal with low oxygen levels just 30 centuries ago, The New York Times reported Monday.
The spread of the new gene is just one instance of recent human evolution and of a specific group changing genetically in response to local conditions, researchers say.
Many scientists once thought humans ceased to evolve in the distant past after people first learned to protect themselves against cold, famine and other harsh agents of natural selection.
But research into human genome sequences around the world has shown increasing evidence of natural selection at work in the last few thousand years, suggesting human evolution is still in progress, the Times said.