Why do some animals have webbed feet?

Webbing gives animals the edge in the water – but how?

An array of species have webbed feet – toes connected through a piece of skin. This interlinking structure has primarily evolved for aquatic locomotion, allowing an animal to swim efficiently to capture prey or flee predators. The webbing structure increases the surface area of the foot, therefore pushing against a greater amount of water, aiding speed and navigation. Such a structure is equally as important above water, as webbing eases walking on unstable surfaces, preventing sinking or loss of balance.

Most aquatic animals have webbed feet, including ducks, frogs, penguins and puffins. Puffins reach depths of up to 61 metres (200 feet) when hunting fish, using their webbed feet as a rudder to navigate, whereas swans simply use their webbed appendages to swim while feeding at the surface.

Some mammals have also evolved with this structure, including beavers, capybaras and even canine species. Newfoundlands, for example, were bred to
work in the cold waters of Canada, relying on their webbed feet, muscular build and thick, water-resistant fur.

Image: Dave Huth/flickr