In Bats and Whales, Convergence in Echolocation Ability Runs Deep:
..."However, it is generally assumed that most of these so-called convergent traits have arisen by different genes or different mutations. Our study shows that a complex trait -- echolocation -- has in fact evolved by identical genetic changes in bats and dolphins." A hearing gene known as prestin in both bats and dolphins (a toothed whale) has picked up many of the same mutations over time, the studies show. As a result, if you draw a phylogenetic tree of bats, whales, and a few other mammals based on similarities in the prestin sequence alone, the echolocating bats and whales come out together rather than with their rightful evolutionary cousins. Both research teams also have evidence showing that those changes to prestin were selected for, suggesting that they must be critical for the animals' echolocation for reasons the researchers don't yet ...
