Question

3. What were the main effects of changing environment around 12,000 years ago?

Answer 1

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there was habitat destruction for many organisms, changes in a parasitic loads and diseases, food chain was destructed, increase in population, the climate change was also affected both directly and indirectly by change in the environment.
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Answer 2

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.Roughly 12,900 years ago, massive global cooling kicked in abruptly, along with the end of the line for some 35 different mammal species, including the mammoth, as well as the so-called Clovis culture of prehistoric North Americans.

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