The beginning of the Eocene Epoch Era.
If proven to be true, a hypothesis can become a theory, a theorem, or a law. Since her hypothesis is proven to be true, it is no longer a hypothesis.
Temporal isolation , behavioral isolation, and geographical isolation I hope I answered your question if not please try searching up or using further sources
Environment, genetics, selective breeding, random mating, random fertilization, recombination, crossing over, etc
Mitochondria and chloroplasts.
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