Mammal is the name for organisms from the class Mammalia, named by Carl Linnaeus in 1758. Mammals are part of the kingdom Animalia. They are distinguished from other species of the kingdom Animalia as they possess hair and mammary glands. They also possess three middle ear bones and a neocortex. Mammals are able to regulate their own body temperature (warm blooded) and have a four chambered heart, as well as a pulmonary and systemic blood circulation systems. With the exception of five species of monotremes (egg-laying mammals), all mammals give birth to live young instead of laying eggs.