They produce an amniote egg, which usually has a leather hard shell that protects the embryo from drying out. This is an advantage over amphibians because the amniote egg can be laid on land where it is usually safer from predators. They also produce amniote eggs but usually give them greater protection from predators by laying them high off of the ground or in other relatively inaccessible locations. H umans are members of the vertebrate class Mammalia . All mammals conceive their young within the reproductive tract of the mother and, after birth, nourish them with milk produced by their mammary glands .
Mammals are heterodonts with unusually strong jaws.
Mammalian heterodontism L ike birds, mammals are endothermic , or warm blooded. They are able to maintain a relatively constant body temperature regardless of external environmental conditions mainly by using internal physiological mechanisms. All other classes of living animals are ectothermic , or cold blooded. They maintain a relatively constant body temperature by absorbing heat from their environments. E ndothermic animals are able to remain active at night and often in the winter when the air temperatures are cold.