Multicellular Evolution Apparently Isn't That Tough and Only Takes 60 Days

By Andrew Tarantola on at

Wait, I thought evolution was an interminably slow process requiring millions of years to make any noticeable difference? Apparently not if you're yeast. A research team has just announce that it's figured out how to evolve a single-celled organism into a multicellular animal just like a freakin' Pokemon.

The team, from the University of Minnesota, was able to artificially evolve a culture of brewer's yeast into it's multicellular form basically by overfeeding it. The culture was housed in flasks and bathed in an extremely nutrient-rich medium.

Once a day, researchers would shake the flasks, then harvested the fast-sinking yeast clumps to start new cultures — the equivalent of natural selection. After just a few weeks, the yeast clumped together and after two months, the clumps had merged into multicelled organisms. What's more, the new creatures showed cell specialisation, a juvenile stage, and multicellular offspring.

"Multicellularity is the ultimate in co-operation," said evolutionary biologist Michael Travisano, co-author of the study. "Multiple cells make make up an individual that co-operates for the benefit of the whole. Sometimes cells give up their ability to reproduce for the benefit of close kin."

So, there you have it. The evolutionary step that expanded Life beyond amoebas probably wasn't powered as much by some revolutionary genetic variation as it was by the bacterial equivalent of a Las Vegas buffet. [Wired]

Image credit: Ratcliff et al./PNAS