Why Do Flamingos Stand on One Leg?

Flamingos spend much of their time wading in water, which draws heat from their bare legs. By tucking one leg up against the body, a flamingo halves the surface area exposed to cold water, conserving body heat. Biomechanical studies have also shown that the flamingo skeleton has a passive locking mechanism at the knee and hip joints, allowing the bird to balance on one leg with virtually no muscular effort — so little, in fact, that deceased flamingos can remain upright on one leg when propped. This effortless balance means the posture saves both heat and energy.