Hunter-gathers

Anthropological research with modern hunter-gatherers suggests an ideal type or model for this kind of society. They were nomadic and exhibited low population size and density—on the order of thirty people per thousand square miles. Paramount in maiiitaining this low size and density was an imperative common to all hunter-gatherer women. A nomad woman had to move herself, all that her family owned (which was very little), and her children at a moments notice. Modern hunters and gatherers often have to walk twenty miles a day, so mothers cannot carry more than one small child. Faced with this restriction, women are careful to space their children so that the two or rarely three children they have... 

This IS also true for human hunter-gatherer societies. Without technology, people use about 1 calorie to gain 5 to 10 calories. The energy return increases to 20 calories through the use of shifting agricultural practices. 

A further characteristic feature of the evolutionary psychology argument is to point to the relatively short period, in geological and evolutionary terms, over which Homo sapiens - and, in particular, modern society - has appeared. Forms of behaviour or social organisation which evolved adaptively over many generations in human hunter-gatherer society may or may not be adaptive in modern industrial society, but have, it is claimed, become to a degree fixed by humanity s evolutionary experience in the palaeolithic EEA. Hence, they are now relatively unmodifiable, even if dysfunctional. 

Konner, M. and Worthman, C. (1980) Nursing frequency, gonadal function, and birth spacing among Kung hunter-gatherers. Science 207, 788-791. 

The Ko and G/wi San (Bushmen) of the Central Kalahari. Samples were also taken from the IKung. These groups represent a model of the hunter-gatherer stage of cultural evolution and thus in many ways an archaic mode of life ... 

Coeliac disease probably arose around 10000 bc when humans switched from the hunter-gatherer way of life to cultivation of cereals (barley, wheat and oats). An illness... 

Humans have not had time to evolve a toxic harmony with all of their dietary plants. The human diethas changed markedly in the last few thousand years. Indeed, very few of the plants that humans eat today, such as coffee, cocoa, tea, potatoes, tomatoes, corn, avocados, mangoes, olives, and kiwi fruit, would have been present in a hunter-gatherer s diet. Natural selection works far too slowly for humans to have evolved specific resistance to the food toxins in these newly introduced plants. 

The appearance of humans on the planet and their own evolution to the status of hunter-gatherer brought a new meaning to the term selection , and our ancestors would have taken the first steps in categorising the available fruits according to flavour character. 

---