Mammals (class Mammalia) are a clade of endotherms that are distinguishable from reptiles and birds by the possession of the mammalian auditory ossicles, mammary glands, and a neocortex.
The brain of a mammal regulates its body temperature and circulatory system, including the four-chambered heart. Mammals comprise some of the smallest and largest animals on the planet, ranging from the 30-40mm bumblebee bat to the 33m blue whale.
The word "mammal" is modern, from the scientific name Mammalia, coined by Swedish botanist, phsysician and zoologist Carl von Linne in 1758. It is in turn derived from the Latin word mamma, meaning "teat" or "pap". Female mammals nurse their young with milk, which is secreted from special glands, known as the mammary glands. With the exception of some monotreme species, most modern mammals also give birth to live young.
List of books: Mammal