Which statement is correct about a bottleneck event?
• A bottleneck event increases the gene pool of a population.
• A bottleneck event decreases the gene pool of a population.
• A bottleneck event decreases the population of a species permanently.
• A bottleneck event increases the population of a species permanently.
The correct statement about a bottleneck event is: "A bottleneck event decreases the gene pool of a population."
A bottleneck event occurs when a population undergoes a sudden and drastic reduction in size, leading to a decrease in genetic diversity. This reduction can be caused by natural disasters, human activities, or other factors. Because only a small subset of the original population survives the bottleneck event, genetic variation is lost, and the gene pool of the population becomes smaller. This can have negative consequences for the long-term survival and adaptation of the species.
To determine which statement is correct about a bottleneck event, we can go through each option and analyze their implications.
1. "A bottleneck event increases the gene pool of a population."
A bottleneck event refers to a sudden decrease in the size of a population due to a catastrophic event. This could be caused by natural disasters, disease outbreaks, or human activities. During a bottleneck event, the population size decreases significantly, which means there are fewer individuals contributing to the gene pool. Therefore, this statement is incorrect.
2. "A bottleneck event decreases the gene pool of a population."
As discussed in the previous option, a bottleneck event results in a reduced population size. With fewer individuals, there is a limited number of genetic variants present in the population, which leads to a decrease in the gene pool diversity. So, this statement is correct.
3. "A bottleneck event decreases the population of a species permanently."
In a bottleneck event, the population experiences a temporary reduction in size. However, it does not necessarily mean that the decrease is permanent. Once the bottleneck event is over, the population can recover and potentially increase again. Hence, this statement is incorrect.
4. "A bottleneck event increases the population of a species permanently."
As mentioned before, a bottleneck event involves a decrease in population size. Therefore, it is not accurate to say that it increases the population, let alone permanently. Thus, this statement is incorrect.
Based on this analysis, the correct statement about a bottleneck event is:
"A bottleneck event decreases the gene pool of a population."