what is disruptive selection explain with example
Answers
Answer:
Disruptive selection is a type of natural selection that selects against the average individual in a population. The makeup of this type of population would show phenotypes of both extremes but have very few individuals in the middle.
eg Darwin’s finches, or Galapagos finches
Answer:
1. In disruptive selection, more number of individuals acquire peripheral character value at both ends of the distribution curve.
2. Nature selects extreme phenotypes and eliminates intermediate. Hence two peaks are formed in distribution of traits.
3. This kind of selection is rare.
4. It ensures the effect on the entire gene pool of the population, considering all mating types or systems.
Example:
(a) It was observed in the different beak size of the African seed cracker finches.
(b) The birds have different kind of beak and they feed on seeds. The available seeds were of two kinds small and large sized seeds.
(c) Large beak sized birds feeds on large seeds while small beak sized birds feeds on small seeds and their number was increased.
(d) Intermediate beak sized birds are unable to feed on either type of seeds so their population was decreased gradually and then were eliminated by natural selection.