Which of the following is not a possible long-term consequence of two organisms occupying the same niche? a. local extinction b. adaptation c. migration d. coexistence

The answer is coexistence.

When two organisms are found in the same niche they can not generally coexist in the long term. But it is possible that one of the two organisms adapts to the lifestyle of the second organism, or one of the two organisms disappears (by extinction or by migration).

The correct answer would be d. Coexistence

This can be explained with the help of the competitive exclusion principle which states that two species occupying the same niche cannot coexist.

It is because they would compete for the same limiting resources and thus the species which has even the slightest survival advantage over another will survive and the other would extinct.

Thus, coexistence is not a possible long-term consequence of two organisms occupying the same niche.