Question

Natural selection operates in different ways in nature. 
(a) (i) Identify the type of natural selection depicted in the graph above. 
 

Hint:

Directional selection shifts the population’s traits toward one extreme due to environmental pressures.

Answer 1

The graph illustrates Directional Selection, a process where environmental pressures favor one extreme phenotype. Key aspects include:
Definition: Directional selection causes a population's traits to shift towards one extreme, benefiting individuals with advantageous characteristics. 
Example: The industrial melanism phenomenon, where darker moths exhibited superior camouflage in polluted areas, leading to increased survival and reproduction. 
Impact: This process drives population evolution, promoting traits that improve adaptation to particular environments.
Directional selection is distinct from:
Stabilizing Selection: Which preserves traits within a narrow range. 
Disruptive Selection: Which favors extreme phenotypes over intermediate ones.