A new era in the study of evolution

Alvin Powell in the Harvard Gazette:

ScreenHunter_2844 Oct. 03 20.06Three years ago, when Harvard biologist Jonathan Losos settled in at the Geological Lecture Hall for a talk by fellow scientist Richard Lenski, he was toying with the idea of writing a book on evolution. When the lecture was over, he was done toying.

Losos, an evolutionary biologist and the Monique and Philip Lehner Professor for the Study of Latin America, said the work described by Michigan State’s Lenski filled in a picture partly painted by experiments Losos already knew about — some of which he had conducted himself, with lizards from the genus Anolis, commonly called anoles, on islands in the Caribbean.

Lenski’s research approximated what the late Harvard paleontologist Stephen Jay Gould, who wrote extensively about evolution, might have described as “replaying the tape of life,” Losos said.

“Gould had suggested that if we could somehow replay the tape — start evolution over again from the same starting point, then we get a very different outcome,” Losos said. But Gould also knew that the project he was describing was impossible, strictly “a thought experiment,” as Losos put it.

“But Lenski showed that you can replay the tape, at least in the lab using microorganisms,” he said. “By starting 12 populations of E. coli that were initially identical and subjecting them all to the same natural selection pressures, he was actually replaying the tape, not going back in time, but letting the tape replay side by side in his 12 experimental replicates.

More here.