Yeast is the first species domesticated by humanity
The first species domesticated by humanity were yeasts, long before dogs, horses, or dairy cows. Micro-organisms like yeasts were in fact a driving force in the agricultural revolution. Bread and beer, to which yeasts are essential, were discovered by pre-Neolithic populations who liked these products so much that they started to intensively cultivate cereals. It was therefore fermented aliments which gave rise to agriculture, and behind this fermentation yeast was used and domesticated by the original farmers.
This initial domestication has defined in many ways the course of humanity. 3000 years before our era, Babylonians utilized the fermentation of yeasts to make a great variety of light, alveolated breads. Not long before, the ritual importance of beer is thought to have been one of the founding elements of pre-Dynastic Egypt. The fermentation of micro-organisms like yeasts also predates fire in its role of softening food, making it more digestible and tasty: humans fermented food before they cooked it 1.9 million years ago. This unknowing use of the yeasts present in the air had significant evolutionary consequences on the shape of our jaw or the size of our brain.
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