Читать книгу The Blood Type Diet Cookbook - Lucy Degremont - Страница 8

The four different blood types, O, A, B and AB, didn’t appear on earth all at the same time. The first three are a product of human evolution and the latter the consequence of As and Bs intermingling.

Man as we know him today appeared on this planet around 40,000BC, in eastern Africa. A branch of anthropology that investigates humankind’s biological differences has concluded that our ancestors and the first men on earth, the hunter-gatherers, were blood type O. All mankind at that time, and for approximately the next 20,000 years, had the same blood type. Around 20,000BC a combination of increased population and depleted hunting grounds forced the hunter-gatherers to migrate to western Africa and the Asian and European continents. As our hunter ancestors adapted their diet and lifestyle to a different environment, their body also underwent a radical change. A new blood type appeared in response to a new man: the farmer. He cultivated grains, reared animals and lived in communities. Type A evolved from type O.

It was another 5,000–10,000 years before another blood type made its appearance as an evolutionary step from the original blood type O: type B. This appears to have been the result of hunter-gatherers migrating from the heat of eastern Africa to the cold conditions in the Himalayas, where Bs are thought to have evolved. These people were either nomads roaming the country to conquer better lands or farmers working the land they had settled on.

Blood type AB, only about 5 per cent of the world population, is the result of marriages between blood type A populations and blood type B populations. This blood type seems to have appeared not much more than 1,000 years ago.

What does all this tell us? Simply that blood groups are not arbitrary – they appeared as a direct response to man’s physical and nutritional environment and those early blueprints laid down for each blood type continue to have relevance to this day.