Thursday, June 19, 2008

News the Anti-Evolution Crowd Won't Want to Hear

According to a story in New Scientist, research has uncovered a major evolutionary shift in an organism right as it was happening. The research involved 12 populations of E.Coli, a bacterium we have all come to know and love, that have been growing in a lab for 20 years. The story notes:

But sometime around the 31,500th generation, something dramatic happened in just one of the populations – the bacteria suddenly acquired the ability to metabolise citrate, a second nutrient in their culture medium that E. coli normally cannot use.

Indeed, the inability to use citrate is one of the traits by which bacteriologists distinguish E. coli from other species. The citrate-using mutants increased in population size and diversity.

"It's the most profound change we have seen during the experiment. This was clearly something quite different for them, and it's outside what was normally considered the bounds of E. coli as a species, which makes it especially interesting," says Lenski.

Lenski further determined that the ability to metabolise citrate was the result of one or more earlier mutations that opened up the possibility. The punch line comes in the last paragraph:

Lenski's experiment is also yet another poke in the eye for anti-evolutionists, notes Jerry Coyne, an evolutionary biologist at the University of Chicago. "The thing I like most is it says you can get these complex traits evolving by a combination of unlikely events," he says. "That's just what creationists say can't happen."

1 comment:

  1. And the best part of the article is that all of the bacteria were descended from a single ancestor. So no one can argue that the trait was already in the population.