Genetic drift, the founder principle, and the bottleneck effect all occur under what conditions?
a. in small populations when one genetic trait becomes more common in a population purely by chance
b. in small populations and result in a decrease in genetic diversity and/or an increase in the occurrence of specific genetic traits
c. when a small group of organisms only reproduce with each other to create a larger population of organisms
d. when the majority of a population is decimated and there are only a few remaining organisms left to rebuild the population
if answered

Answer;

d. when the majority of a population is decimated and there are only a few remaining organisms left to rebuild the population

Explanation;

-Genetic drift can have major effects when a population is sharply reduced in size by a natural disaster (bottleneck effect) or when a small group splits off from the main population to found a colony (founder effect).

-Population bottlenecks occur when a population's size is reduced for at least one generation. Because genetic drift acts more quickly to reduce genetic variation in small populations, undergoing a bottleneck can reduce a population's genetic variation by a lot, even if the bottleneck doesn't last for very many generations.

Genetic drift, the founder principle, and the bottleneck effect all occur under the conditions when the majority of a population is decimated and there are only a few remaining organisms left to rebuild the population. The answer is letter D. 

the correct answer is option b

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