Michigan State University researchers show that more adaptable bacteria that are oriented toward long-term improvement prevailed over competitors that held short term advantages.
Credit: NSF/Karson Productions
Audio Transcript:
Take Your Time -- It's Evolution.
I'm Bob Karson with the discovery files -- new advances in science and engineering from the National Science Foundation.
An evolutionary study of generations of bacteria reads a lot like the fable, 'the tortoise and the hare.'[2] Led by the University of Michigan, it showed that if you're a bacteria, sometimes it's better to be a slow, adaptable tortoise than a fitness-oriented hare.
In the fable, the hare is all like full of himself and instantly gets way out front. So far ahead, he figures he can take a nap. By the time he wakes up, the tortoise is plodding across the finish line.
How does that relate to bacteria? The MSU study recorded evolutionary change over an unprecedented 52,000 generations of bacteria grown over 25 years. The team was able to clone two distinct lineages from a population of frozen E. coli[3]. Welcome to bacterial family feud! And here we go!
One lineage makes a mutational move early in the game that gets them ahead initially, but closes off certain routes for later improvement and eventually winds up extinct. The other lineage is less fit early on, but over the course of several evolutionary moves, produces more beneficial mutations, overcoming its short-term disadvantage. By maintaining greater potential for further adaptation, the tortoises prevail.
Turtle power!
"The Discovery Files" covers projects funded by the government's National Science Foundation. Federally sponsored research -- brought to you, by you! Learn more at nsf.gov or on our podcast.
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Notes:
[1] Slow V.
“Slo-V” is a slow flying model aircraft. For more information, please visit
http://en.wikipedia.org/wiki/ParkZone_Slo-V
[2] the tortoise and the hare
it is a fable attributed to Aesop. The story concerns a hare who ridicules a slow-moving tortoise and is challenged by him to a race. The hare takes a nap midway through the course. When he awakes, he finds that the tortoise has won the competition.
[3] E. coli / Escherichia coli
A bacterium commonly found in the intestines of humans and other animals, where it usually causes no harm. Some strains can cause severe food poisoning, esp. in old people and children. 大腸桿菌
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