Over generations, female reindeer in a Finnish population give birth to larger offspring. Which type of selection occurring, and how would a distribution curve for this trait change over time? (1 point)

Question

Stabilizing selection, the curve would become taller in the middle

Stabilizing selection; the curve would become shorter in the middle

Directional selection, the curve would shift to the left

Directional selection; the curve would shift to the right

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? (1 point)

stabilizing, a tail, narrow peak in the center of the graph

disruptive, two peaks at either end of the graph with a dip in the middle

disruptive; a tall, narrow peak in the center of the graph

stabilizing: two peaks al either end of the graph with a dip in the middle

Paleontologists observed changes in the sizes of black bears as their environment changed. During warmer periods between ice ages, most black bears were small. During ice ages, most black bears were large. Which type of selection is this, and how would a graph of the distribution curve of black bear size change as Earth moved out of an ice age? (1 point)

disruptive; the curve would break into two peaks with a dip in the middle

stabilizing the curve would become taller in the middle and shorter on each side

directional; the curve would shift to the right

directional, the curve would shift to the left

Answer 1

1. For the first question regarding the Finnish population of female reindeer giving birth to larger offspring, the correct option is:

   • Directional selection; the curve would shift to the right. This indicates that over generations, the average size of the offspring is increasing, resulting in a shift in the distribution curve towards larger sizes.

2. For the second scenario of mice with medium brown fur being less likely to be seen by predators, the correct option is:

   • Stabilizing, a tall, narrow peak in the center of the graph. This is because medium brown mice are favored, leading to a concentration of the population around that trait, resulting in a narrow peak representing the most advantageous fur color.

3. For the observation of black bear sizes during warmer and ice age periods, the correct option is:

   • Directional; the curve would shift to the right. This indicates that as the climate warms and smaller bears are less favored (with larger bears being favored during ice ages), the average size of the black bear population shifts over time towards larger sizes as the ice age concludes.