Owls are largely nocturnal birds of prey with sharp talons, upright postures, broad heads, and binocular vision. Their hearing is so good they can hear prey under dirt, leaves or snow. In many species of owls, the ears are at different heights on their heads. The small difference in sound wave reception caused by the position of the ears allows the owl to pinpoint the exact location of hidden prey. The flattened face of an owl serves as a feathered sound collector.