Evolution and Human Uniqueness

"This work presents a novel account of the emergence of distinctively human forager lifeways; those that emerged at the end of the Pleistocene, before the formation of large-scale societies organised around agriculture, hierarchy, and ultimately state powers. The account contrasts with others in four major respects. First, it sees the increasing divergence of the hominin lineage from great ape patterns as driven by positive feedback amongst a number of initially small differences, rather than by a key innovation. Second, it identifies an environmental trigger of that initial divergence. Late Pliocene and/or early Pleistocene hominins had an opportunity to move into a scavenging niche, whereas chimp ancestors did not. Once in that niche, there was an incremental pathway to increasing investment in cooperation, social learning, and technology, pulling human ancestors away from great ape lifeways. Third, while the account shares with Michael Tomasello the view that the early expansion of cooperation was a form of immediate return mutualism (with cooperation being immediately and individually rewarding), the analysis here shows how defended and confrontational scavenging lead to the suppression of dominance hierarchies, making many other forms of cooperation profitable, and opening a pathway to the distinctive and unusual egalitarianism of forager cultures. Fourth: the account shares with others the view that cumulative social learning played a critical role in the establishment of human lifeways. But it offers an alternative account of the factors making accumulation possible. On most accounts, cumulation depends on specific cognitive adaptations that make high fidelity social learning possible. Instead, on the analysis here, it depended on an adapted learning environment with much informational redundancy; much collaboration amongst those learning, with help from the adult generation; and on hybrid learning, combining both social and natural information"-- Provided by