In a population of mice, individuals with medium brown fur are less likely to be seen by predators than light brown and dark brown mice. What type of selection is this, and what would the distribution curve for the mouse population look like?
a. disruptive; a tall narrow peak in the center of the graph
b. stabilizing; a tall, narrow peak in the center of the graph
c. stabilizing; two peaks at either end of the graph with a dip in the middle
d. disruptive; two peaks at either end of the graph with a dip in the middle
The type of selection described is stabilizing selection. Stabilizing selection favors individuals with an average or intermediate phenotype and selects against individuals with extreme phenotypes. In this case, mice with medium brown fur are at an advantage since they are less likely to be seen by predators compared to light and dark brown mice.
The distribution curve for the mouse population would have a tall, narrow peak in the center of the graph, representing the high frequency of medium brown mice. The curve would taper off towards the ends, representing the decreasing frequencies of light and dark brown mice.
The type of selection described in this scenario is stabilizing selection. Stabilizing selection occurs when individuals with intermediate traits have a higher fitness compared to individuals with extreme traits. In this case, the medium brown mice have a higher fitness because they are less likely to be seen by predators.
When visualizing the distribution of the mouse population, stabilizing selection tends to result in a tall, narrow peak in the center of the graph. This indicates that the majority of the population falls within the intermediate trait range, in this case, medium brown fur. So, b. stabilizing; a tall, narrow peak in the center of the graph is the correct answer.
The correct answer is c. stabilizing; two peaks at either end of the graph with a dip in the middle.
This is an example of stabilizing selection because individuals with medium brown fur, representing the middle of the distribution, are less likely to be seen by predators. As a result, selection pressure favors individuals with fur colors that are either lighter or darker, leading to two peaks at either end of the distribution curve. The dip in the middle represents the reduced fitness of individuals with medium brown fur.