The finding has come about via a new way of examining the behaviour of hummingbirds in the wild. This finding, based on biological field work, reveals the tongues to be like long, skinny pumps.
This finding turns established biological theory on its head. Many researchers though (and some still do) that hummingbirds sip from plants by nectar flowing up open grooves in the tongue in a similar way to how water rises inside thin capillary tubes. Instead the birds draw up the sweet fluid using a tiny pump mechanism.
As noted in the research brief: “during the offloading of the nectar inside the bill, hummingbirds compress their tongues upon extrusion. The compressed tongue remains flattened until it contacts the nectar surface, after which the tongue reshapes, filling entirely with nectar.”
According to The Washington Post, this means “the bird rapidly reshapes its tongue, and that change in tension draws sweet nectar into their mouths.”
To arrive at this conclusion, biologists examined 96 foraging bouts of 32 focal birds belonging to 18 species. Hummingbirds are among the smallest of birds, with many of the different species measuring 3–5 inches. The birds are known as hummingbirds due to the humming sound created by their beating wings. They also have among the highest metabolisms of any animal.
The finding has been made by Alejandro Rico-Guevara of the University of Connecticut in Storrs. Dr. Rico-Guevara is a special type of biologist called a functional morphologist.
The research has been published in the Proceedings of the Royal Society B. The article is headed “Hummingbird tongues are elastic micropumps.”
In related news, research indicates that hummingbirds can accomplish sustained flight that is at least as efficient as that of the most high-tech micro-drone helicopter.