Modern humans (Homo sapiens, ssp. Homo sapiens sapiens) are the only extant members of the subtribe Hominina, a branch of the tribe Hominini belonging to the family of great apes. They are characterized by erect posture and bipedal locomotion; high manual dexterity and heavy tool use compared to other animals; and a general trend toward larger, more complex brains and societies. Early hominins—particularly the australopithecines, whose brains and anatomy are in many ways more similar to ancestral non-human apes—are less often referred to as "human" than hominins of the genus Homo. Several of these...