Human evolution is the part of biological evolution concerning the emergence of humans as a distinct species.
It is the subject of a broad scientific inquiry that seeks to understand and describe how this change and development occurred.
The study of human evolution encompasses many scientific disciplines, most notably physical anthropology, linguistics and genetics.
The term "human," in the context of human evolution, refers to the genus Homo, but studies of human evolution usually include other hominins, such as the australopithecines.
Paleoanthropology is the study of ancient humans based on fossil evidence, tools, and other signs of human habitation.
The modern field of paleoanthropology began in the 19th century with the discovery of "Neanderthal man."
The eponymous skeleton was found in 1856, but there had been finds elsewhere since 1830.
Homo genus In modern taxonomy, Homo sapiens is the only extant species of its genus, Homo.
Likewise, the ongoing study of the origins of Homo sapiens often demonstrates that there were other Homo species, all of which are now extinct.
While some of these other species might have been ancestors of H. sapiens, many were likely our 'cousins', having speciated away from our ancestral line.
There is not yet a consensus as to which of these groups should count as separate species and which as subspecies of another species.
In some cases this is due to the paucity of fossils, in other cases it is due to the slight differences used to classify species in the Homo genus.