If you're speaking of the Africans the Europeans later enslaved, no they did not treat them fairly. The Europeans continued to force African slaves to work for them with no pay for years until slavery was abolished.
A decrease or increase of a certain population can affect the food chain of an ecosystem
Lets say bugs start dying at a rapid rate in an swamp ecosystem
The frog population would then decrease because they have no bugs to eat
The frog’s predators would then decrease because of the number of frogs to eat are decreasing.
So on and so forth.
Hope this helps!
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