Flamingos stand on one leg because they’re using the other to sleep.
Flamingos are often spotted standing on one leg, and while it might look like they’re balancing, the reason is actually much more bizarre. The birds have evolved to use one of their legs as a sort of built-in crutch while they sleep. This is because flamingos have very little muscle mass in their legs, so it makes sense for them to prop themselves up in order to reduce strain on their joints. While flamingos aren’t actually standing on one leg when they sleep, the position does make it easier for them to fall asleep. Their lack of muscle mass also means that if a flamingo falls asleep with both legs off the ground, it will likely wake up with a sore back.
