How are sea snake tails adapted for swimming?

Sea snakes have evolved specialized tails to navigate their aquatic environments. The tail is laterally flattened to form an oar-like structure, which the snake uses to scull through the water. This adaptation significantly increases the animal's locomotor power, allowing it to move efficiently through its marine habitat.123

While sea snakes utilize lateral undulations of the body for propulsion—similar to the swimming motion of eels—the flattened tail serves as a critical component in enhancing their swimming performance. In contrast to terrestrial snakes, this specialized tail shape is essential for life in the water, though it renders most advanced sea snake species nearly helpless when they are on land.321