The real story
A ruby-throated hummingbird's heart beats around 1,260 times a minute in flight, and it may visit 1,000 to 2,000 flowers a day just to keep up. Burning energy that fast, it can't stay 'on' all night: it drops into torpor, a nightly mini-hibernation in which its heart can slow to under 50 beats a minute and its body cools down.
Before migrating it eats until it has nearly doubled its weight. Some birds then fly nonstop across the Gulf of Mexico, up to about 800 km of open water with nowhere to land or feed, a trip of roughly 18 to 22 hours. Others take the long way round along the Texas coast. Either way, it is an astonishing distance for a bird of about 3 grams.