Wednesday, March 16, 2011

Animals hedge their bets in natural selection

Melbourne: Just like humans, other animals also hedge their bets, and understanding this may help explain how nature will respond to future climate change, says expert.

Andrew Simons of Carleton University in Ottawa argued ''bet-hedging'' is a neglected evolutionary strategy used by living organisms in general, to cope with changing environments.

"It could be much more important than previously thought," ABC Science quoted Simons, who has reviewed 100 papers reporting bet-hedging in a broad range of life including micro-organisms, plants, insects, birds and reptiles, as saying.

There are a number of evolutionary strategies that life uses to respond to changing environments, said Simons.

They may adapt their physiology or behaviour to maximise their chance of survival. For example, water fleas have evolved to be capable of growing protective armour in response to chemical signals from fish predators.

Simons said there is a third aspect of natural selection that we need to pay more attention to. It's a way of managing risk called bet-hedging that humans themselves use when, say, diversifying stock market investments.

"Over the long term we know that environments are quite variable. Bet-hedging allows you to survive despite those fluctuations... it reduces the chance all out failure,” he said.

This strategy allows for a diversity of genotypes that includes traits that may not be advantageous in the short term, but will ensure an organism survives in a particular extreme environment.

Simons said it is important to find out how prevalent bet-hedging is in nature, and to make some generalisations as what kinds of organisms evolve it.

The findings have been reported in the Proceedings of the Royal Society B.

ANI

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