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daniel_i_l
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I recently came across this article:
http://www.newscientist.com/article/dn14094-bacteria-make-major-evolutionary-shift-in-the-lab.html
Lenski's freezer must be an immensely valuable source of evolutionary information.
And one question, why is "lower peak population densities" something E. coli would evolve towards. Wouldn't the more successful ones have a higher population density?
http://www.newscientist.com/article/dn14094-bacteria-make-major-evolutionary-shift-in-the-lab.html
Has anything on this scale ever been observed before?A major evolutionary innovation has unfurled right in front of researchers' eyes. It's the first time evolution has been caught in the act of making such a rare and complex new trait.
And because the species in question is a bacterium, scientists have been able to replay history to show how this evolutionary novelty grew from the accumulation of unpredictable, chance events.
...
Mostly, the patterns Lenski saw were similar in each separate population. All 12 evolved larger cells, for example, as well as faster growth rates on the glucose they were fed, and lower peak population densities.
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.
Lenski's freezer must be an immensely valuable source of evolutionary information.
And one question, why is "lower peak population densities" something E. coli would evolve towards. Wouldn't the more successful ones have a higher population density?
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