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Hummingbirds Have Sweet-Seeking Receptors Other Birds Lack
The desert Southwest boasts one of the richest varieties of hummingbird species on the planet. A possible reason can be from their unique sense of taste.
Here in Arizona, if you have a feeder you’ve probably seen hummingbirds drink the sugar water you’ve put in there.
But how hummingbirds detect sweetness is different from how we do it. In fact, hummingbirds are different from most animals that have a sweet taste receptor. They lack it.
So how do they detect the sweetness of nectar?
A new study published in Science suggests hummingbirds adopted the savory receptor to also taste sweetness, a sensation most birds can’t have. Not only can hummingbirds taste it, they have an acute ability to sense when something is sweet.
“The hummingbirds, when they are feeding, the sticker comes out seventeen times a second into nectar, which is superfast," said Harvard University researcher Maude Baldwin. "And, what we saw is that hummingbirds can tell within three tongue licks, or 160 milliseconds in the video, that what they are feeding on is not sugar, that it’s water so they can discriminate very rapidly.”
That immediate response indicated a sweetness receptor must be present, a unique evolution to help find a sweet drink in the desert.