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Homo sapiens (Latin: wise human) is a biological species, a mammal and the only surviving species of the genus Homo. The species is commonly referred to as "humankind", "humanity", "humans", "people". (Also sometimes called "man" or "mankind", but that usage is discouraged these days on the grounds of gender neutrality.) Misplaced Pages is contributed to by members of this species.

Homo sapiens is among the most generalized species on Earth and inhabit nearly all landmasses (a "generalized" trait is one that is suited to many different functions; an organism that is highly generalized can survive in a greater variety of environments). In terms of population size or diversity of species, smaller and simpler animals such as bacteria and insects dominate the Earth's species, however. Some human beings consider themselves to be the "dominant" species, and most advanced in intelligence and ability to manage its environment. This belief is especially strong in Western culture, and is based in part in the Biblical creation-story. Many natural scientists, especially those who work within Darwin's theory of evolution of species through natural selection reject this view.

Some of the closest living evolutionary relatives to humans are the hominids chimpanzees, orangutans and gorillas.

The evolution of genus Homo spans over 2 million years and the fossil record is far from complete; as paleoanthropologists discover new evidence, models of human evolution change. Anthropologists generally recognize three species of hominenes: ''Homo habilus'', Homo erectus, and Homo sapiens. In the late Pliocene or early Pleistocene (2 - 2.5 million years b.p.) two lines of hominids diverged in South and East Africa: the Australopithecines and the first species of genus Homo, Homo habilus. Both genera were bi-pedal. H. habilus had smaller molars and larger brains than the Australopithecines, and tools made from stone and perhaps animal bones.

In the Early Pleistocene, from 1.5 to 1 million years b.p. Hominines in Africa, Asia, and Europe, evolved larger brains and more elaborate stone tools; these differences and others are sufficient for anthropologists to classify them as a new species, Homo erectus. The direct evidence suggests that there was a migration out of Africa of H. erectus, then a further speciation of H. sapiens from H. erectus in Africa and a subsequent migration out of Africa which replaced dispersed H. erectus. There is little evidence that this speciation occurred elsewhere, even though some fossil evidence for H. erectus has been found in China. However, the current evidence doesn't preclude multiregional speciation, either. This is a hotly debated area in paleoanthropology.

Between 400, 000 years b.p. and the second interglacial period in the Middle Pleistocene, around 250,000 years b.p., the trend in cranial expansion and the elaboration of stone tool technologies developed, providing evidence for a transition from H. erectus to H. sapiens. Anthropologists currently identify two subspecies of H. Sapiens: neanderthaloids, and modern humans (originally identified as Cro-Magnon). Current evidence suggests that the two subspecies diverged during the fourth glacial period around 40,000 years b.p., after which neanderthaloids died out.

Important fossils:

Petralona, Greece, about 300k years old. Contained many features of H. erectus.

Arago, France, about 300k years old. Oldest skull clearly of H. sapiens origin.

The origins of humanity is a subject of great political and religious controversy in the United States and certain other countries. See: creationism.