Their long tongues work like tiny elastic pumps.
Advertisement
What is actually taking place, the researcher report, is that during the offloading of the nectar inside the bill, hummingbirds compress their tongues upon extrusion. For this reason, instead of using vacuum to generate suction – imagine drinking lemonade out of a straw – the system works like a tiny pump, powered by the springiness of the tongue. 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.
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.
Observations and measurements were taken from seven countries throughout the Americas where free-living, never handled hummingbirds were feeding at modified transparent feeders simulating nectar volumes and concentrations of hummingbird pollenated flowers.
After a large chuck of time passed, they observed that a hummingbird’s tongue works like a micropump. When the bird inserts its tongue into the nectar compartment of the flower, the tongue is expanded and it immediately fills up with nectar. The only hummingbird found east of the Mississippi is the Ruby-throated Hummingbird, so the researchers had to go further afield to gather a broad sample.
[When hummingbirds don’t get the sweet stuff, they get mad].
However, a team of scientists from the University of Connecticut has now debunks this capillary action or “wicking” theory after observing 18 different species of hummingbirds that are feeding in the wild with the help of high speed cameras as scientists revealed that hummingbirds drink nectar not like a straw but with tiny, pumping action with their tongues.
Advertisement
“Our research shows how they really drink and provides the first mathematical tools to accurately model their energy intake, which will in turn inform our understanding of their foraging decisions and ecology”, lead researcher Alejandro Rico-Guevara said in a statement.
