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Video: Holy Papillae, Batman!

Credit: Cally Harper/Brown University

How many licks does it take to get to the center of a nectar-rich flower? For Pallas's long-tongued bat (Glossophaga soricina), just one. The tiny bats, which live in North and South America, feed mostly on nectar and pollen from flowers. Though they have a cute face, you probably wouldn't want a kiss from one. Each side of the animal's tongue is lined with hundreds of compressed, millimeter-long bristles called papillae. Scientists wanted to see the tongue in action, so they used high-speed video to record the bats feeding on sugar water. As the bats lapped up the solution, the papillae stiffened, the researchers report online today in the Proceedings of the National Academy of Sciences. The researchers found that as the tongue extends, its muscles contract, squeezing blood into the tongue tip and then the papillae, which become erect. That increases the tongue's surface area even more, which likely helps rake in more delicious nectar. The researchers hope that studying the bat tongue could serve as a model for surgical tools that would, for example, widen blood vessels or the small intestines from the inside.

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