hominins

Hominins are the human lineage, consisting of modern humans (Homo sapiens) and all extinct species more closely related to humans than to chimpanzees. In many classifications, the group includes the genus Homo and several closely related extinct forms that lie along the lineage after the split from the chimpanzee lineage. The fossil record shows that the earliest hominins appeared in Africa about 6–7 million years ago, with species such as Sahelanthropus tchadensis, Orrorin tugenensis, and Ardipithecus.

A defining early trait of hominins is bipedalism, the ability to walk upright on two legs, which is reflected in pelvis and leg anatomy and is thought to be an adaptation to energy-efficient locomotion and environmental changes. Over millions of years, hominins exhibit trends toward larger brains, changes in dentition, and diversified body forms. The genus Homo emerges around 2.8–2.4 million years ago, with Homo habilis among the earliest members and likely associated with more advanced stone-tool use. Subsequent species include Homo erectus, Homo heidelbergensis, and the lineages that gave rise to modern humans, Neanderthals (Homo neanderthalensis), and other relatives.

Homo sapiens appeared in Africa roughly 300,000 years ago and later dispersed globally, often interacting with and sometimes interbreeding with other hominins such as Neanderthals and Denisovans. Genetic evidence supports limited interbreeding and helps explain some aspects of modern human variation. Taxonomic definitions of Hominini and related groups have varied, reflecting ongoing debates about where to draw species and genus boundaries within this long and complex evolutionary history.