The list of endangered species known as Red List. This listing plants & animals that are facing the threat of extinction worldwide. This list revised every 2 years. So to say, one fourth of all the mammals are present in the list. All species of elephants, rhinos, gorillas, orangutans, chimpanzees, most species of whales, and half of all vertebrates [ animals having spinal column or notochord ] living in freshwater are too part of the list.