Monday, January 25, 2010

Coevolution of Bat & Dolphin Echolocation

Echolocation in dolphins and bats evolved separately, but through the same genetic changes.

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Dolphins and bats have both evolved the same specialized form of inner-ear hair cells that allow them to use sophisticated echolocation: detecting unseen obstacles or tracking down prey by making a high frequency noise and listening for the echo that bounces back.

"The natural world is full of examples of species that have evolved similar characteristics independently" said Stephen Rossiter. "However, it is generally assumed that most of these so-called 'convergent traits' have arisen by different changes in the animal's DNA. Our study shows that this very complex ability - echolocation - has in fact evolved by identical genetic changes in bats and dolphins."

Kamandi © DC Comics
According to Rossiter, the discovery represents an "unprecedented" example of convergence between two very different animals, and suggests that further studies might unearth more genetic similarities between species than scientists would have suspected. link
Ref.: Convergent sequence evolution between echolocating bats and dolphins. 2010. Y. Liu, et al. Current Biology 20: R53-R54, 26.