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Hummingbirds are ravenous. These tiniest of birds have the highest metabolism
of any warm blooded animal.
And they’re fueled by flower nectar.
To get it, they’ve developed skills no other birds have.
They can fly backwards and hover for long stretches of time.
Their beaks stay steady like a surgeon’s scalpel,
but their wings beat furiously, up to 80 times a second.
And they can hover in wind. In rain even.
Most of these birds weigh less than a nickel.
You’d think they’d get blown away.
So how do they pull it off?
Scientists at UC Berkeley brought hummingbirds into the lab for a closer view.
First, the wild birds had to be trained, one at a time, to feed from an artificial flower
filled with sugar water.
Hummingbird wings buzz like helicopter blades - too fast for the naked eye to see.
But by recording them with a high-speed camera – at 1000 frames a second -- scientists
can see the individual wing movements. They can actually see how hovering works.
Most birds flap their wings up and down to fly. But hummingbirds move their wings backward
and forward in a figure eight movement, like oars.
This generates lift during the upstroke and the downstroke, which helps hummingbirds stay
stable, instead of bobbing up and down.
But how would a hummingbird respond when the weather gets rough?
To find out, the scientists moved the hummingbird into a wind tunnel and began recording.
The wind is coming from the right side of t he cage – up to 20 miles per hour.
The hummingbird must fly into the wind to get the sugar water.
This high-speed footage shows how it turns and twists its body in the direction of the
air flow, while using its wings for control and its tail like a rudder to stay steady.
Even rain can’t stop the hummingbird from feeding.
See how the bird shakes off drops of water from its body, like a wet dog?
The birds can’t afford not to eat. They have to consume their weight in nectar
every day to survive.
And the flowers need them too. As they eat, hummingbirds spread pollen from plant to plant.
It’s a symbiosis – a two-way street between a bird and a flower.
These tiny flying machines have evolved ways to hold up their end of the bargain,
rain, wind or shine.