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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.

The closest living evolutionary relatives to humans are the two species of chimpanzee Pan troglodytes ("common chimp") and Pan paniscus ("pygmy chimp" or "Bonobo"), and to a lesser degree other hominids such as orangutans and gorillas.

Homo sapiens Compared to Other Species

Humans are often considered to be the "dominant" species on Earth, and the most advanced in intelligence

and ability to manage their environment.

This belief is especially strong in Western culture, and is based in part in the Biblical creation story

in which Adam is explicitly given dominion over the Earth and all of its creatures.

Biologists and scientists in general, though, do not consider "dominant" to be a useful term,

as it is usually intended to mean superiority, and superiority can be interpreted in many ways.

From a scientific standpoint, homo sapiens certainly is among the most generalized

species on Earth.

Smaller and simpler animals such as bacteria and insects greatly surpass humans in population

size and diversity of species, but few single species occupy as many diverse environments as humans.

Many other species, for example, are adapted to specific environments where humans rely on external tools

such as clothing and manufactured shelter.

The use of tools and the ability to alter their environment (building shelter, weaving fabrics for clothing,

etc.) has been cited as a characteristic which distinguishes humans from other animals, but this view is

now generally rejected by ethologists who have recorded such behaviors in many species.

Apes and even birds, for example, are known to "fish" for insects using blades of grass or twigs, and

even to shape the tools for that purpose.

No other animal uses tools to the same degree or with the

same flexibility as homo sapiens.

A more likely candidate for a distinguishing characteristic of Homo sapiens is the use of language.

Other animals often have simple methods of communication, but the degree to which humans create

and use complex grammar and abstract concepts in language has not been seen in any other species,

despite much effort to find it.

Some biologists think that these readily observable characteristics (toolmaking and language) are based on

a less easily observable mental process that might be unique among humans: the ability to think symbolically.

That is, humans can think abstractly about concepts and ideas.

They can question, use logic, understand mathematical concepts, and so on in ways that no other animals

are known to do, although several species have demonstrated some ability in this area.

This belief is why the species was named Homo sapiens, sometimes translated as "Man the Thinker".

The evolution of Homo sapiens

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 (There is ongoing debate over whether "Neanderthal Man" was a separate species, Homo neanderthalensis, or a subspecies of H. sapiens. The latter view is currently more popular).

H. habilus, the first species of genus Homo, evolved in South and East Africa in the late Pliocene or early Pleistocene (2 - 2.5 million years before present) when it diverged from the Australopithecines. Both genera were bipedal. 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 ago, hominines in Africa, Asia, and Europe, evolved larger brains and made more elaborate stone tools; these differences and others are sufficient for anthropologists to classify them as a new species, Homo erectus.

Between 400,000 years ago and the second interglacial period in the Middle Pleistocene,

around 250,000 years ago, the trend in cranial expansion and the elaboration of stone tool technologies developed, providing evidence for a transition from H. erectus to H. sapiens. 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 the 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.

Anthropologists currently identify two subspecies of H. sapiens: neanderthaloids, and modern humans (originally identified as "Cro-Magnon Man"). Current evidence suggests that the two subspecies diverged during the fourth glacial period around 40,000 years ago, 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.