Amphibians, reptiles and fishes make up 70-percent of all the known living vertebrates (animals with backbones). Though animals are still being discovered, there are at least 20,000 different species of fish, 5,000 species of amphibians and 6,000 species of turtles, snakes, lizards and crocodiles! Sedgwick County Zoo tries to represent this huge diversity with careful selection.