Answer:
Immunity to Small Pox
Explanation:
Over the years, Europeans had built up an immunity to smallpox because many had contracted the disease and still survived. As the population grew children were born with some immunity to the disease. When the Europeans arrived in the Americas, and smallpox spread around the native peoples, the Europeans did not contract the disease because they were immune. However, since the natives were not immune, they slowly died of due just to the disease as well as some parts of the war between the europeans.
The Answer to this question is b
When a top predator is removed from an ecosystem, a series knock-on effects are felt throughout all the levels in a food web, as each level is regulated by the one above it. This is known as a trophic cascade. The results of these trophic cascades can lead to an ecosystem being completely transformed. The impacts trickle down through each level, upsetting the ecological balance by altering numbers of different animal species, until the effects are finally felt by the vegetation.
