A small, isolated island population of finches experiences a drastic reduction in population size due to a volcanic eruption. The surviving finches have a different average beak size compared to the original population. This change is primarily attributed to:
Directional selection
Founder effect
Bottleneck effect
Disruptive selection
Related Questions
Resistant varieties evolved in much lesser time because of
Natural selection
Faster rate of mutation
Anthropogenic (human) activities
Random selection
