Final answer:
Homo habilis, a species within the genus Homo, emerged from an australopithecine lineage about 2.5 to 3 million years ago and exhibited advances such as a larger brain and early tool use.
Step-by-step explanation:
Species within the genus Homo emerged from one australopithecine lineage about 2.5 to 3 million years ago. The genus Australopithecus, which includes species such as Australopithecus africanus, lived between two and three million years ago and is thought to be ancestral to our genus, Homo. One of the first known species in the genus Homo was Homo habilis, which lived from about 2.5 to 1.4 million years ago and may have been ancestral to Homo erectus. This transition marks a significant evolution in hominins, with Homo habilis demonstrating more advanced features such as a larger brain and reduced jaw prognathism compared to its australopithecine ancestors. Furthermore, Homo habilis is often associated with the earliest known stone tools, indicating the advent of more complex behaviors.