Bats and toothed whales share the ability to squeak and click their way to prey. And now two new studies in this week’s journal Current Biology reveal that their echolocation, which evolved independently in the two groups, has a similar underlying molecular mechanism.
There are plenty of examples of evolutionary convergence, such as the tusks of elephants and walruses, or the bioluminescence of fireflies and jellyfish.
But it’s highly unusual for convergence to occur at the molecular level. Turns out the inner ear hair cells of both the bottlenose dolphin (a toothed whale) and 10 species of bats contain a protein called prestin, which plays an important role in echolocation.
But not all echolocaters are created equal. Because the speed of sound in water is five times that in air, dolphins can use echolocation for more than 100 meters. Bats can only do so for a few meters.
(Hat tip to Monterey Bay’s Sea Notes blog for this story.)