Interdigital webbing

Interdigital webbing is the presence of membranes of skin between the digits. Normally in mammals, webbing is present in the embryo but resorbed later in development, but in various mammal species, it occasionally persists in adulthood. In humans, it can be found in those suffering from LEOPARD syndrome and from Aarskog–Scott syndrome.

Webbing between the digits of the hindfoot is also present in several mammals that spend part of their time in the water. Webbing accommodates movement in the water.

Interdigital webbing is not to be confused with syndactyly, which is a fusing of digits and occurs rarely in humans. Syndactyly specifically affecting feet occurs in birds (such as ducks), amphibians (such as frogs), and mammals (such as the kangaroo).