According to National Geographic, although hummingbirds love nectar they don’t even have a sweet taste receptor, like most birds. But a new study in Science says that the birds (that can be as small as some thumbs) outsmarted evolution by “repurposing” their umami receptor - the evolutionary receptor responsible for identifying savory meat flavors - to taste and enjoy sweet nectar. It was never in the evolutionary cards for hummingbirds to have a major sweet tooth, but somehow they made it happen.
Maude Baldwin, the Harvard University doctoral student who led the 3 year study, said it is definitely not the norm for “such a complicated function being regained over the course of evolution.” In hummingbirds, the umami receptor had a considerable amount of mutations: hummingbirds changed 19 of their protein-building amino acids. That’s a major feat for such a tiny being. Baldwin believes that these mutations helped hummingbirds taste sugar, and to also respond to the artificial sweeteners that are so bad for us. However, they were smart enough not to want anything to do with aspartame - a common substance found in artificial sweeteners and diet drinks.
But hummingbirds don’t just get happy about sugary-nectar wholesomeness. Although they are teeny, hummingbirds are fierce, meat-eating predators, too. Their long, thin and sharp beaks are optimal for grubbing on bugs, and getting in some much-needed protein.
Research such as this is critical because we need pollinators like the hummingbird. The Canadian Wildlife Federation claims that these pollen-transferring and nectar-drinking animals contribute over a billion dollars every year to the Canadian economy by keeping up food supplies. These hard-working animals also keep our planet healthy by keeping the (genetic) diversity of our plants balanced. They also keep vulnerable species of plants safe. Hummingbirds, in particular, eat flies and gnats and keep parasitoid laying eggs away.
Story and photo via Care2.com