How hummingbirds can fly at high altitudes

[Still Waters]

Hummingbirds have the highest metabolic rates among vertebrates, and have heart rates of up to 1,260 beats per minute, so it's difficult to imagine them flitting about in an environment where oxygen is scarce. But a study published today in the Proceedings of the National Academy of Sciences Early Edition uncovers how these species have evolved the capacity to flourish at very high altitudes.

http://phys.org/news...h-altitude.html

[Keel M.]

I wonder if the hum of their wings sounds different in higher altitudes.

[Emin]

I was once reading a book on hummingbirds, they discussed how they evolved to the flower or how the flower evolved to suit the hummingbird and how they've adapted over time with changes and migrations, evolution is quite a complex and tricky thing, however very fascinating.

[Willie B Herd]

Also when the hummer is at rest its heart rate is about 400 per min, and slows to a mere 40 per min while sleeping, (in a state similar to hybernation) and this is the only way the bird can survive without eating for that long.

[Willie B Herd]

Another program stated that they can breath up to 500 times per minute!