Origins (1979)

Leakey & Lewin           translation in progress

• The sharing as triggering of human evolution (impact of free hands and body)
• The stimulation as key element of the evolution
• An Adaptation that involves behavioral change

The key to transforming a monkey-like social creature into a cultivated animal, living within a structured society, is sharing: sharing of work and sharing of food

The hunter-gatherer integrates with the natural order, out of necessity into small groups, while the farmer necessarily contravenes the harmony of nature. But there is more: sedentary farming communities (12,000 years ago) are tempted to increase their goods (human materialism), are thus led to protect them (human aggressiveness) and allow the appearance of urban anthills (civilizations, empires, states).

The secret of human evolution lies in an extreme flexibility of adaptation. The only somatic change that allowed this evolution was the liberation of the hands. It opens the way to technology through the manufacture and manipulation of tools.

• Change in diet (man goes from vegetarian to omnivorous thanks to organized hunting, tools, …)
• The skull, now balanced at the vertex of the spine, can develop and allow an increase in brain mass.
• Ability to carry food and water (hands, bags, .. migration, safety, ..)
• Protection against predation (fire and security, group, weapons, food reserve, …)
• Change within the social organization (fire, group, …)
• Community life allows prolonged education during childhood (more effective knowledge of the environment where they live)
• A very specialized activity strongly stimulates group solidarity: it is the sharing of food (spoils of gathering and hunting)
• Migration (fire, heat, water transport, ..) then trade
• Being vegetarian means being essentially lonely
• Fire, while keeping predators away and increasing the lighty period of the day, brought men together (heat) giving them the opportunity to tell stories, create myths and rituals
• Group hunting has considerable advantages, provided that participants act with coordination (wolves, lions, ants, ..)
• Agriculture amplifying the phenomenon of trade (grain versus meat or tools), requiring social cooperation (increased interpersonal relations) and specialization of activities (division of labor). The key to the mixed economy is sharing (work and food).
• Farmers are forced into sedentary life. In return, this offers for the first time, the possibility of amassing material goods, creating a new aspect of human behavior (materialistic, aggressive, ..).
• The agricultural economy can support a much higher population density, hence villages and cities, communities where intimacy (easy in a group of 20) becomes impossible.
• With the extension of populations, interdependent through trade, appears the possibility of the establishment of power on the masses, on a scale unknown to hunter-gatherers (is the man is basically aggressive or is it? this a consequence of evolution – carnivore then farmer?)
  
  

Hands capable of handling and a subtle language are the essential faculties of a cultured animal.

The brain has not only evolved in size, but it has also specialized (lobes, left and right brain). It represents barely 2% of the body weight, but to function, it requires 15% of the blood circulation and consumes 20% of the total oxygen supply.

The early development of the human brain is the corollary of an arboreal life: stereoscopic vision (binocular vision facilitates the appreciation of distances) associated with prehensile hands revealed to primates a three-dimensional world, imperceptible to other mammals. In the environment, objects acquire their own meaning because they can now be grasped and explored. Amplification of the 5 senses together, coordinated, and memory (collection, interpretation and categorization of information).

In general, non-human primates have trouble focusing on a single activity for a long time. They lack perseverance. A good hunter animal must possess a quality, tenacity.

Notes:

The word Homo is the name of the biological genus that groups together all human species. They are all extinct with the exception of Homo sapiens.

The earliest discovery of fossil remains is the Red Lady of Paviland in 1823 (Roman era). Archeology is recent (anthropology).

 

In conclusion, the human brain simply has the capacity to learn, to be adaptable to many situations in the environment.

note:

How will the technological revolution change the world and the human brain? Will you continue to share work and food with the rest of the world when 2/3 of the population is not eating out?