In a very large population, a quantitative trait has the following distribution pattern:

-If the curve in the previous figure shifts to the left or to the right, there is no gene flow, and the population size consequently increases over successive generations. Which of the following is (are)probably occurring?
1)immigration or emigration
2)directional selection
3)adaptation
4)genetic drift
5)disruptive selection
A) 1 only
B) 4 only
C) 2 and 3
D) 4 and 5
E) 1, 2, and 3

Question

In a very large population, a quantitative trait has the following distribution pattern:
 
-If the curve in the previous figure shifts to the left or to the right, there is no gene flow, and the population size consequently increases over successive generations. Which of the following is (are)probably occurring?
1)immigration or emigration
2)directional selection
3)adaptation
4)genetic drift
5)disruptive selection
A) 1 only 
B) 4 only 
C) 2 and 3 
D) 4 and 5 
E) 1, 2, and 3

Quizplus · Accepted Answer

Directional selection and adaptation are likely occurring if a curve shifts to the left or right without gene flow and the population size increases. Directional selection implies that individuals with traits on one end of the spectrum are more likely to survive and reproduce, causing a shift in the population's characteristics. Adaptation occurs as the population becomes better suited to its environment through this process.

In a Very Large Population, a Quantitative Trait Has the Following