Question

how can the bottleneck effect result in the development of a new species? allele frequency decreases and is so different from the original population that speciation occurs. allele frequency stays exactly the same resulting in no change in the population. allele frequency increases so much that nothing changes within the population.

Explanation:

The bottleneck effect reduces population size. This leads to genetic drift, changing allele frequencies. If these frequencies differ enough from the original population, reproductive isolation (a key part of speciation) can occur. The first option correctly describes allele frequency change leading to speciation. The second option is wrong as allele frequency doesn't stay the same in a bottleneck (due to genetic drift). The third option is incorrect because an increase in allele frequency (without significant change relative to the original) won't cause speciation; it's the difference in allele frequencies that matters for speciation.

Answer:

Allele frequency decreases and is so different from the original population that speciation occurs.