Many animal species inhabit the North American prairie, but compared to other ecosystems, the biodiversity (variety of wildlife) is rather low. There are different insects and spiders as well as vertebrates such as amphibians, reptiles, birds and mammals. With so many grasses to eat, herds of ungulates are often found in prairies. Ungulates are hoofed mammals like pronghorn and bison. These grazers are right at home on the prairie. They benefit the prairie soil by stirring it up with their pointed hooves as they move around.