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.
From Harvard
Medical School.
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