Thaindian News

Washington, March 23 (IANS) Greater adaptability rather than fitness is the key to survival, as exemplified by the much slower tortoise than the faster hare.

Richard Lenski, professor of microbiology and molecular genetics at the Michigan State University, and colleagues show that more adaptable bacteria prevailed over competitors that held a short-term advantage.

The discovery that the less-fit organisms overtook their very fit counterparts surprised the researchers at first. But it turns out to work something like a game of chess, the journal Science reports.

“In games, it makes sense to sacrifice some pieces for an eventual winning move,” said Lenski, co-principal investigator of the study, according to a Michigan statement.

“The eventual winners were able to overcome their short-term disadvantage over the course of several evolutionary moves by producing more beneficial mutations,” he added.

Lenski is recognised as a leading evolutionary experimentalist, recording evolutionary change over 52,000 generations of bacteria grown during nearly 25 years.

He and his team recently revived a frozen population of E. coli and compared the fitness and ultimate fates of four clones representing two genetically distinct lineages.

One lineage eventually took over the population even though it had significantly lower competitive fitness than the other lineage that later went extinct.

“In essence, the eventual loser lineage seems to have made a mutational move that gave it a short-term fitness advantage but closed off certain routes for later improvement,” Lenski said.