Why are there so few domesticated species?
The existence of only a low fraction of evolutionarily plastic species can also explain the fact that man succeeded in domesticating only a negligible number of plant and animal species. Only plastic species can adapt to the drastically changed conditions of life in captivity without significant decreases in viability and fertility. The frozen plasticity theory suggests that domestication should be successful mostly in young species, which have not yet had enough time to freeze.
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