Grey wolves have long embodied the spirit of the wilderness. Once they had the largest natural distribution of any mammal except humans. Sadly, they can no longer claim this record as they have been lost from much of their former lands. Grey wolves still occupy a range of habitats including Arctic tundra, prairies and forests.
Although melanin is found in the skin of many species, in the reptiles, the amphibians, and fish, the epidermis is often relatively colourless. Instead, the colour of the skin is largely due to chromatophores in the dermis, which, in addition to melanin, may contain guanine or carotenoid pigments.kin of a different nature exists in amphibians, reptiles, and birds. All mammals have some hair on their skin, even marine mammals which appear to be hairless. The skin interfaces with the environment and is the first line of defense from external factors.
Most amphibians also have four limbs. Limbs and lungs  are adaptations for life on land; the limbs evolved from the  ancestral fishes' lobed fins. The scales and amenity egg evolved by  reptiles are further adaptations for life on land and distinguish  reptiles from amphibians.he skin in the mouth of some amphibians works the same way as their skin and allows them to respire (You can see this when they allow air flow-it looks like they're breathing normally but in their throat). Long powerful legs that allow it to jump and swim very well.