How hummingbirds evolved to detect sweetness

[Judi Lynn]

How hummingbirds evolved to detect sweetness

Date: August 21, 2014

Source: Harvard Medical School

Summary:

Hummingbirds' ability to detect sweetness evolved from an ancestral savory taste receptor that is mostly tuned to flavors in amino acids. Feasting on nectar and the occasional insect, the tiny birds expanded throughout North and South America, numbering more than 300 species over the 40 to 72 million years since they branched off from their closest relative, the swift.

Everything about hummingbirds is rapid. An iridescent blur to the human eye, their movements can be captured with clarity only by high-speed video.

Slowed down on replay, their wings thrum like helicopter blades as they hover near food. Their hearts beat 20 times a second and their tongues dart 17 times a second to slurp from a feeding station.

It takes only three licks of their forked, tube-like tongues to reject water when they expect nectar. They pull their beaks back, shake their heads and spit out the tasteless liquid. They also are not fooled by the sugar substitute that sweetens most diet cola.

These hummingbirds look mad.

The birds' preference for sweetness is plain, but only now can scientists explain the complex biology behind their taste for sugar. Their discovery required an international team of scientists, fieldwork in the California mountains and at Harvard University's Concord Field Station, plus collaborations from Harvard labs on both sides of the Charles River.

More:
http://www.sciencedaily.com/releases/2014/08/140821141449.htm?utm_source=feedburner&utm_medium=feed&utm_campaign=Feed%3A+sciencedaily+%28Latest+Science+News+--+ScienceDaily%29

[Demit]

1. Funny, how they'll spit out water if it has no sugar in it.

This is my first year having hummers to watch & I've loved it. Feisty buggers! They sure let me know when the feeders need filling. I learned that Huitzilopochtli, the Aztec God of War, is portrayed as a hummingbird. I'll be sorry when they migrate, they've given me a lot of pleasure.

[shenmue]

2. Nom nom nom

Glurp glurp glurp.

[BlueJazz]

3. Besides the cool stuff, they're just adorable.

[Lionel Mandrake]

4. It makes sense that hummingbirds would evolve this way,

since they need lots of energy to do so much flying.

I wonder if any other birds have evolved a sense of sweetness.