Some bats chug nectar with conveyor belt tongues

To figure out how nectar-feeding bat tongues work, researchers recorded hairy-tongued bats (such as Glossophaga soricina) and grooved-tongued bats (such as Lonchophylla robusta, shown) feeding on bromeliads and other flowers.

M. Tschapka/University of Ulm

By Helen Thompson

September 29, 2015 at 6:30 am

A subset of bats that eat off the nectar menu sip from flowers using specialized tongues that pump liquid up to their mouths, researchers report September 25 in Science Advances.

Nectar-feeding bat tongues come in two varieties: hairy and groovy. By analyzing high-speed videos of bats feeding, ecologists found that the two anatomies translate to vastly different feeding behaviors. Most nectar-feeding bats have tiny hairs called papillae at the end of their tongues that allow the bats to lap up nectar as cats do milk.

But grooved-tongued bats (Lonchophylla robusta in this study) actually pump nectar up their tongue without breaking contact with the liquid — unlike any other mammal but strangely like a conveyor belt. Capillary action and tongue distortion probably push nectar up the tongue, the researchers write.