The medicinal use of animals for the benefit of humans, zootherapy, dates all the way back to the medieval period. Many indigenous peoples around the world rely solely on the use of plants and animals for the healing and treatment of their people. These ancient uses of animals have often led to scientific research of the specific uses of animals and compounds developed from animals in modern medicine. The use of leeches is a well-know type of zootherapy that has recently been approved by the FDA. The venom of cone snails is also being studied and used in pain relief for people who suffer from cancer and other painful diseases. Also, there are studies being done on the ability of arctic mammals, such as the arctic ground squirrel, to survive in subzero temperatures during hibernation. Scientists are looking to incorporate this in organ transplants to prolong the life...