The Emergence of Humanity

Adaptation to the savanna and transition to bipedality probably triggered the divergence of the hominins from other apes in Central-Eastern or Southern Africa between 5 and 7 MYA. The human lineage (here identified with the genus Homo) appeared between 3 and 2 MYA, its earliest distinctive traits being increased brain size, the loss of fur, improved thermoregulation, and arm/torso anatomy adapted to high-energy throwing. Coercive suppression of conflict of interest probably favoured kinship-independent aggregation into cooperative groups. Cooperative hunting and social rearing improved the diet, thus providing the extra resources necessary for the development of larger and metabolically more active brains under selection pressure for higher cognition. In a complex network of mutual interactions, kinship-independent cooperation paved the way to the evolution of language and the emergence of culture, a body of shared knowledge and beliefs transmitted across generations. Culture accumulation and donated culture triggered cultural niche construction, the development of a continuously expanding environment, partly physical and partly cognitive and social, which was the main driver in the evolution of modern humans (Homo sapiens). Sapiens appeared in Eastern Africa around 200 KYA, migrated to the Middle East twice, around 100 and 70 KYA, and from there started a worldwide expansion about 60 KYA. Fire became embedded very early in human behaviour and was involved in almost all technological advances. The transition to food production, from about 11.5 KYA, was pivotal to the emergence of modern societies. Most genomic changes that distinguish humans from their primate relatives are in non-coding sequences with regulatory functions.