Hummingbird tongues may work like micropumps

Scientists have collaborated with experts in the field of fluid mechanics where they have tested on numerous hypotheses where the team was able to reveal the physics behind this micro pumping action while feeding. Because of its particular shape and the fact that it has a hollow interior, scientists believed that the basis of the bird’s feeding process was capitalization, a natural phenomenon that allows liquids from two containers to communicate due to the difference in pressure. “Fluid at the tip is driven into the tongue’s grooves by forces resulting from re-expansion of a collapsed section”, remarks Rico-Guevara.

In an article for The Conversation, Rico-Guevara and Hurme explain that birds are incapable of using their tongues as straws, so instead of generating suction, “the system works like a tiny pump, powered by the springiness of the tongue”. Scientists thought that the long, narrow grooves they saw on hummingbird tongues accomplished the same feat.

The study’s methodology surpasses that of previous hummingbird research, Professor Rubega said in a university news release, because it comes closer than ever to approximating real-life conditions. Their data shows that fifty years of research describing how hummingbirds and floral nectar have coevolved will have to be reconsidered. They discovered that hummingbirds drink by using their tongues as “elastic micropumps”.

Those grooves drawn in nectar when they expand after having been squeezed by the beak, functioning as tiny pumps that draw rather than wick the liquid. The design used transparent tubes filled with artificial nectar, with cameras set up nearby.

The experiment involved different kinds and species of hummingbirds, which included 32 birds.

[When hummingbirds don’t get the sweet stuff, they get mad].

The new study was published Wednesday in Proceedings of the Royal Society B: Biological Sciences.

This new study shows how hummingbirds drink and feed on nectar with the first real mathematical model that can accurately depict their energy intake using these micro pumping actions that add to the better understanding of how hummingbirds forage for food and their overall ecology, adds Rico-Guevara.