structural:scholar_edition, linguistic:voice_change
Gelasian

The Lower Paleolithic began with the appearance of the first stone tools in the world. Formerly associated with the emergence of Homo habilis, some 2.8 million years ago, this date has been pushed back significantly by finds of the early 2000s, the Oldowan or Mode 1 horizon, long considered the oldest type of lithic industry, is now considered to have developed from about 2.6 million years ago, with the beginning Gelasian (Lower Pleistocene), possibly first used by australopithecine forebears of the genus Homo (such as Australopithecus garhi).

However, even older tools were later discovered at the single site of Lomekwi 3 in Kenya, in 2015, dated to as early as 3.3 million years ago. As such, they would predate the Pleistocene (the Gelasian), and fall into the late Pliocene (the Piacenzian).

The early members of the genus Homo produced primitive tools, summarized under the Oldowan industry, which remained dominant for nearly a million years, from about 2.5 to 1.7 million years ago. Homo habilis is assumed to have lived primarily on scavenging, using tools to cleave meat off carrion or to break bones to extract the marrow.

The move from the mostly frugivorous or omnivorous diet of hominin Australopithecus to the carnivorous scavenging lifestyle of early Homo has been explained by the climate changes in East Africa associated with the Quaternary glaciation. Decreasing oceanic evaporation produced a drier climate and the expansion of the savannah at the expense of forests. Reduced availability of fruits stimulated some proto- australopithecines to search out new food sources found in the drier savannah ecology. Derek Bickerton (2009) has designated to this period the move from simple animal communication systems found in all great apes to the earliest form of symbolic communication systems capable of displacement (referring to items not currently within sensory perception) and motivated by the need to "recruit" group members for scavenging large carcasses.

Homo erectus appeared by about 1.8 million years ago, via the transitional variety Homo ergaster.