The Human Robber Hypothesis: Humans Used Fire to Steal Prey from Large Carnivores, Thereby Providing the Brain with Nutrients to Enlarge It after Birth

Genes and Environment

Shizuyo Sutou¹ 

[1] School of Pharmacy, Shujitsu University

关键词: brain enlargement;    carnivore;    cooked meat;    eccrine gland;    hairlessness;    humanization;   

DOI  :  10.3123/jemsge.2014.017

学科分类：分子生物学，细胞生物学和基因

来源: Japanese Environmental Mutagen Society / Nihon Kankyo Hen igen Gakkai

【 摘 要 】

References(22)Cited-By(1)Bipedalism paved the way to delivery of immature babies and development of the brain after birth. This communication presents the argument that hairlessness allowed hominins to access fire through wildfires, which occurred frequently after a climate shift from a wet to a dry environment 2.5 million years ago (Ma). Initially, naked hominins approached fire for warming, but soon must have come across burnt animals in the aftermath of wildfires. They learned the taste of burnt meat, which must have been a driving force compelling them to become meat-eaters. Hominins must have learned gradually how to control fire and how to repel hairy animals that abhor fire. Because they could neither run fast nor have muscles sufficiently strong to compete with large carnivores' fangs and claws, they chose not to be hunters but robbers. When they found that a carnivore had killed a prey animal, they approached the hungry predator and repulsed it using fire and stones, then claiming the prey intact. This is the core of the human robber hypothesis. The timing of global cooling, the appearance of savannahs, the appearance of transitional humans, decline of large predators, the manufacture of stone tools, and the start of cooking largely coincide at 2.5 Ma. They also smoked out animals from their dens or caves, and robbed them of shelter and territory. Cooked meat is both tasty and easily digested, providing hominins with rich nutrients sufficient to enlarge the brain, while most large carnivores were forced to extinction. Consequently, the use of fire, facilitated by hairlessness, must have played important roles in protecting hominins from cold, in repelling predators, in robbing large carnivores of prey and dwellings, and in providing the brain with nutrients for strong growth into adolescence. Development of the eccrine glands is also discussed as a result of hairlessness.

【 授权许可】

Unknown