The Turkey vulture (Cathartes aura) also known in some North American regions as the turkey buzzard, and in some areas of the Caribbean as the John crow or carrion crow, is the most widespread of the New World vultures and was was given its common name due to its superficial resemblance to the Wild Turkey – bald red head and dark feathers. Its scientific name is Cathartes aura which is Latin for "cleansing breeze". The Turkey Vulture is one of the few birds able to use its sense of smell to locate food. In fact, the turkey vulture has the largest olfactory (smelling) system of all birds. It often will fly low to the ground to pick up the scent of ethyl mercaptan, a gas produced by the beginnings of decay in dead animals. Turkey vultures are the only scavenger birds that can't kill their prey – their feet are useless for ripping into prey, but the vultures have powerful beaks that can tear through even the toughest cow hide. They feed by thrusting their heads into the body cavities of rotting animals. In spite of their large size, they only weigh between 2-4 pounds. And because of their light weight, turkey vultures can virtually float in the sky using the thermal currents (rising columns of air) to get around the skies. This technique uses very little energy as the vultures rarely need to flap their wings.