Natural Selection 2
Fitness in Present Environment
3
Beak Depth
A graph here shows the average frequency of beak depth for a species of birds in an area. There is a higher frequency of intermediate
beak depths, with some variation within the population for beak size.
A homeowner removes the native landscaping that contained trees and shrubs that formed fruits and nuts. The homeowner plants
new trees that produce only larger sized nuts. No more smaller berries or intermediate fruit food sources are available
What is the most likely impact of the change in the food supply within the homeowner's vicinity? Select ALL that apply.
A)
B)
There will be a decrease in frequency for beak sizes labeled at point 2 on
the graph
Natural selection will likely favor an increase in frequency for beak sizes at
point 3 on the graph
Individual birds will migrate to the area, increasing the frequency of beak
sizes at point 1 on the graph.
The population of birds will change over time with regard to its beak
frequency due to directional selection
The population of birds will change over time with regard to its beak
frequency due to stabilizing selection,
E)