What change is observed in a distribution curve for a trait affected by directional selection?(1 point)
Responses
It shifts either to the right or to the left.
It shifts either to the right or to the left.
It shifts to the right.
It shifts to the right.
It shifts to the right and to the left.
It shifts to the right and to the left.
It shifts to the left. .
?
The answer is "It shifts either to the right or to the left." Directional selection occurs when individuals with a certain extreme phenotype are favored over the others, causing the distribution curve to shift in the direction of that phenotype. This shift may be towards the right or left, depending on which phenotype is being favored.
In a population of birds, brightly colored males and very dull males survive best. Which type of selection is this, and what is most likely true about the proportion of males of intermediate coloring?(1 point)
Responses
Directional; males of intermediate coloring make up the greatest part of the population.
Directional; males of intermediate coloring make up the greatest part of the population.
Directional; males of intermediate coloring make up a small part of the population.
Directional; males of intermediate coloring make up a small part of the population.
Disruptive; males of intermediate coloring make up a small part of the population.
Disruptive; males of intermediate coloring make up a small part of the population.
Stabilizing; males of intermediate coloring make up the greatest part of the population.
Stabilizing; males of intermediate coloring make up the greatest part of the population.