Why do flamingos stand on one leg?
Actually, there isn't just one answer. Let me share what we do know.No single reason has been settled yet. Because flamingos stand on one leg more often when it is cold or when they are in water, one idea is that it keeps body heat from escaping. A 2017 study also showed that in the one-legged pose, their bodies can support their weight while using almost no muscle.
They sometimes sleep on one leg
Flamingos stand on one leg for long periods and sometimes even sleep that way. There are several ideas about why they use one leg, and no single answer has been settled yet. Here are the main ideas that research has looked into.
The keeping-warm idea
Researchers from an American university watched Caribbean flamingos at a zoo. The share of birds resting on one leg was higher when they were in water than on land, and it went down as the temperature went up. Water easily takes heat away from the body, so the idea is that by tucking one leg up against the body, they lose less heat.
A body that uses almost no muscle
In 2017, a study by the Georgia Institute of Technology and Emory University found that even the body of a flamingo that had died could support its weight without muscles when placed in the one-legged pose. It could not be supported in a two-legged pose. Living birds also swayed very little when they rested on one leg with their eyes closed.
Research is still going on
From these results, standing on one leg is thought to possibly save energy, but this has not been tested directly. Another observation found that water temperature made no difference, so there may be more than one reason.
Want to know more?
- When resting on one leg, flamingos had no preference for left or right and switched between both legs.
- In the observations, flamingos took longer to start walking after resting on one leg than after resting on two.
- In the one-legged pose, the body is held up by a kind of "locking" design: the knee does not bend easily one way but moves easily the other way.
Quick quiz: test yourself
What is one leading idea for why flamingos stand on one leg?
Show the answer
- To watch for enemies
- To dry each leg in turn
- To keep body heat from escaping
To keep body heat from escaping Flamingos stand on one leg more often when it is cold or when they are in water, so one idea is that it keeps in body heat. The reason is not settled yet.
Flamingos stand on one leg more often when it is cold or when they are in water, so one idea is that it keeps in body heat. The reason is not settled yet.
Next quiz ›Sources
- Mechanical evidence that flamingos can support their body on one leg with little active muscular forceBiology Letters（PubMed Central掲載）
- Why do flamingos stand on one leg?Zoo Biology（Wiley）
- Ask Smithsonian: Why Do Flamingos Stand on One Leg?Smithsonian Magazine
This article was written after checking the sources above as of 2026-10-03. Explanations may change as research progresses. Photo credits are shown below each photo.
