They already had domesticated turkeys and also along the coast ate fish.
The Aztec also cultivated Spirulina a high protein algae which they grew
in the surrounding lakes. Aztec also cultivated Amaranth one of the few
grains which is high in complete proteins. Incas had domesticated the
Guinea Pig as live stock food source as well as cultivated a grain
Quinoa which is also high in complete proteins. Mesoamericans had
plenty enough protein in their diet to stay healthy.

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