Tuesday, December 1, 2009
Secret to Hummingbirds Drinking Nectar
A hummingbird can extract nectar by wrapping its tongue into a straw. But how could it since viscosity makes sucking liquid more difficult as the straw becomes smaller?
Research at MIT has discovered that the hummingbird is taking advantage of surface tension - what allows water striders to skim across water. When a hummingbird sticks its tongue into a flower, the tongue compresses from 3/4in long to 1/25in in diameter.
The tongue closes, nectar is drawn up, and the "straw" fills with nectar. The hummingbird then scrapes its tongue clean and swallows. It repeats this process 20x/second during feeding.
The discovery holds promise for researchers building miniature chemistry laboratories — "labs on a chip" — that move tiny droplets of chemicals from place to place.
Here's a video of hummingbirds feeding.