Question

the diagram shows a population before and after a chance event.
which statement describes how the new population is formed after the chance event?
a. the new population reproduced with a larger gene pool, which increased diversity.
b. the new population reproduced with a smaller gene pool, which decreased diversity.

Explanation:

1. Compare gene pools: The original population had 4 distinct alleles (red, green, purple, blue), while the new population has only 3 (red, purple, blue) with the green allele eliminated.
2. Assess diversity: Loss of an allele and shifted frequencies (original equal 0.25 frequencies vs. new uneven frequencies with red dominant) confirm reduced genetic diversity.
3. Evaluate options: Option A is incorrect because the gene pool is smaller and diversity decreased, not increased. Option B matches the observed change: the surviving small group (from the chance event) reproduced to form the new population, which has a smaller gene pool and lower diversity.

Answer:

B. The new population reproduced with a smaller gene pool, which decreased diversity.