Across the animal kingdom, feet come in an astonishing variety of shapes, and are equipped with an impressive array of highly specialized adaptations.

Some feature sturdy claws that can burrow tunnels in densely-packed dirt. Others sport sharp, curving talons for catching and clutching fast-moving, squirmy prey. They may use gripping structures to scale vertical surfaces, or deploy venomous spikes to defeat rivals or predators.

Whether they're used as digging tools, grasping suckers or killing machines, animal feet can be downright bizarre. Here are some of the most intriguing examples.