Depending on the species, birds have varying feet anatomies. Despite the variation, ostriches are unique in that they have only two toes on each foot, whereas most birds have three or four. One of an ostriches' two forward pointing toes is larger and has a claw like nail. They kick with their powerful legs and feet to defend against predators.
Most other birds have three or four toes, often with one or two toes pointing backward. Ostriches are also unique in that they are the biggest birds in the world. They can grow up to nine feet and can weigh up to 350 pounds.
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