strangebiology:

sciencenewsforstudents:

Why do flamingos stand on one leg? Flamingo researchers get asked this question all the time. But why flamingos ever bother standing on two may be the bigger puzzle, new research suggests.

Flamingos have balance aids built into their bodies, the new study finds. That lets them stand on one leg with little muscle effort. The stance is so stable that a bird sways less (to stay upright) when it appears to be dozing than when it’s awake.

From the article:

Researchers learned more from the whole bodies of a few dead Caribbean flamingos that a zoo had donated to them. “The ‘ah-ha!’ moment was when I said, ‘Wait, let’s look at it in a vertical position,’” Ting remembers. All of a sudden, the bird specimen settled naturally into a one-legged lollipop stance. There was no way a dead bird could be putting muscle effort into keeping that position. So the body must have some built-in ways to hold this stance without effort.