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How do the hind legs of frogs help them leap and swim?

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natterjack toad (Bufo calamita) — frog and toad The natterjack toad (*Bufo calamita*) lives in northern Europe.

Frogs, which belong to the order Anura, possess specialized hind legs that are essential for both leaping and swimming.

Leaping

Most frogs move by leaping, a form of locomotion facilitated by their long, powerful hind limbs. These legs are significantly longer than the frog's head and body, providing the leverage necessary for distance. To initiate a jump, the frog crouches and then rapidly straightens its hind legs. This action, combined with the snapping open of the knee joint, propels the animal through the air.123

Swimming

For swimming, frogs rely on these same elongated hind legs, which are typically enlarged and strongly webbed. The webbing increases the surface area of the feet, allowing the frog to push against the water more effectively. In most species, the hind legs move synchronously to provide thrust, though they may occasionally alternate during slower swimming. This adaptation makes many frogs highly efficient in aquatic environments.142