Mattosaurus, Wikimedia Commons

Slower-evolving bacteria start slow, but their gradual adaptation means they take advantage of later mutations passed up by faster-evolving bacteria -- and eventually out-evolve their speedier rivals -- according to research led by SFI Science Board member Richard Lenski.

Research carried out in Lenski's lab at Michigan State University on two lineages of E. coli shows that rapidly evolving 'hare' bacteria were eventually wiped out by slower adapting 'tortoise' bacteria.

The researchers sampled the bacteria after 500, 1,000 and 1,500 generations of evolution. By looking for the presence of five beneficial mutations, the researchers found that 'hare' bacteria had more advantageous genetic changes than 'tortoises' after 500 generations, suggesting they were more likely to go on to successfully survive and reproduce, and to eventually wipe out their competitors altogether.

But looking at the later generations, the team found that 'tortoises' had overtaken 'hares' and gone on to dominate the population.

Read the paper in Science (March 18, 2011)

Watch a video interview with Richard Lenski (March 22, 2011)

Read the New York Times article (March 21, 2011)

Read the Nature article (March 17, 2011)

Read the Science News article (March 17, 2011)

Read the New Scientist article (March 17, 2011)

Read the Discover magazine article (March 17, 2011)

Read the Michigan State University news release (March 18, 2011)

Read the Evolution News & Views article (April 18, 2011)