Which of the following are true of natural selection?
Select all that apply.
A. It reduces the frequency of unfavorable traits in a population.
B. It results in overpopulation.
C. It increases the frequency of unfavorable traits in a population.
D. It increases the overall fitness of the species.
A and D?
To determine which of the options are true of natural selection, we need to understand the concept of natural selection itself.
Natural selection is the process by which certain traits become more or less common in a population over time, based on their influence on an organism's ability to survive and reproduce. This process is driven by three key factors: variation, heredity, and differential reproductive success.
Now let's evaluate each of the options:
A. It reduces the frequency of unfavorable traits in a population.
This statement is true. Natural selection favors traits that increase an organism's chances of survival and reproduction, while unfavorable traits have a lower chance of being passed on to future generations. Over time, this leads to a decrease in the frequency of unfavorable traits in a population.
B. It results in overpopulation.
This statement is not necessarily true. While natural selection can lead to population growth if favorable traits increase an organism's chances of survival and reproduction, it does not necessarily result in overpopulation. Other factors such as limited resources or competition can impose constraints on population size.
C. It increases the frequency of unfavorable traits in a population.
This statement is false. Natural selection operates based on the principle of favoring traits that increase an organism's fitness and survival. Consequently, unfavorable traits have a lower chance of being passed on, leading to a decrease in their frequency within a population.
D. It increases the overall fitness of the species.
This statement is true. Natural selection acts to increase the overall fitness of a species by favoring traits that enhance an organism's ability to survive and reproduce. As a result, the frequency of these advantageous traits increases over time, leading to the improvement of the species' fitness.
Therefore, the correct options are A and D.