Question 1

Question

A) Researchers plotted a distribution curve for leg length in a population of birds, with length from
short to long on the x-axis. The curve shifts to the right after a disturbance. Which statement is
correct about natural selection in this population of birds? (1 point)
Birds with medium-length legs were selected for.
Birds with long legs and birds with short legs were selected for.
Birds with short legs were selected for.
Birds with long legs were selected for.
Question 2
A) In peppered moth populations, light and dark moths are selected for in different environments.
Which type of selection is this, and what would a distribution curve for all peppered moths look
like? (1 point)
disruptive selection; two peaks at the extremes of the graph with a dip in the middle
disruptive selection; a tall, narrow peak in the center of the graph
stabilizing selection; two peaks at the extremes of the graph with a dip in the middle
stabilizing selection; a tall, narrow peak in the center of the graph
Question 3
A) Over generations, female reindeer in a Finnish population give birth to larger offspring. Which
type of selection is occurring, and how would a distribution curve for this trait change over time?
(1 point)
directional selection; the curve would shift to the left
stabilizing selection; the curve would become taller in the middle
directional selection; the curve would shift to the right
stabilizing selection; the curve would become shorter in the middle
Question 4
A) 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 tall, narrow peak in the center of the graph
stabilizing; two peaks at either end of the graph with a dip in the middle
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
Question 5
A) 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)
directional; the curve would shift to the left
disruptive; the curve would break into two peaks with a dip in the middle
directional; the curve would shift to the right
stabilizing; the curve would become taller in the middle and shorter on each sid

Answer 1

Here are the answers to your questions regarding natural selection and distribution curves:

Question 1:

• Correct Statement: Birds with long legs were selected for.

Question 2:

• Type of Selection and Distribution Curve: Disruptive selection; two peaks at the extremes of the graph with a dip in the middle.

Question 3:

• Type of Selection and Change in Distribution Curve: Directional selection; the curve would shift to the right.

Question 4:

• Type of Selection and Distribution Curve: Stabilizing; a tall, narrow peak in the center of the graph.

Question 5:

• Type of Selection and Change in Distribution Curve: Directional; the curve would shift to the right.

Feel free to ask if you need further explanations or clarifications!