The population of American bison used to number in the millions of animals. Hunting and other problems greatly decreased the number of bison to about 1,000 animals. Today, the numbers are recovering to estimates of more than 200,000 animals. This crash in the population of bison and recent recovery is an example of .

The correct answer is "the bottleneck effect".

Explanation:

The bottleneck effect, also known as a population bottleneck or genetic bottleneck, is defined as sharp reduction of a species population that occurs either by environmental effects or as a consequence of human activities. The dramatical crash the that population of American bison had due to hunting and other problems is an example of a species suffering the bottleneck effect.

the answer would be 2, if crossing over doesn’t occur 2 out of 4 of the daughter cells will have that allele.

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