A bottleneck event reduces the population of bears in one area by 80%. Which statement is correct about the bears’ gene pool?

Question

1. It has temporarily increased, so disadvantageous traits are more likely to be passed on.
2. It has temporarily decreased, so disadvantageous traits are more likely to be passed on.
3. It has temporarily decreased, so disadvantageous traits are less likely to be passed on.
4. It has temporarily increased, so disadvantageous traits are less likely to be passed on

Answer 1

The correct statement about the bears' gene pool after a bottleneck event is:

2. It has temporarily decreased, so disadvantageous traits are more likely to be passed on.

A bottleneck event significantly reduces the genetic diversity of a population due to the loss of a large portion of the population. This reduction in population size can lead to a decreased gene pool, making it more likely that deleterious (disadvantageous) traits can be passed on, as there are fewer individuals to contribute to the next generation's genetic inheritance. Additionally, the surviving population may not represent the original genetic variation, which can further entrench any disadvantageous traits.