7. Integument (outer boundary layer) 1. Color variation of skin a.Sun protection b. Dominance displays 2. Provides protection by derivatives such as hooves, claws, nails, horns and antlers. 3. Holds hair/fur: (evolved from scales) 4. Holds glands a. Sweat b. Sebaceous c. Scent
Mammals, class Mammalia , are represented by more than 5,000 species. Kitti’s hognosed bat from Thailand weighs 1.5 g. Blue whales exceed 130 metric tons.