Question

What is a factor needed for natural selection to occur?

a) Different fitness levels of the offspring
b) Overproduction of offspring
c) Variation is heritable
d) All of these
e) None of these

Answer 1

Natural selection occurs when there are differences in fitness among members of a population. The factors needed for natural selection include variation of traits among individuals, competition for limited resources, and more offspring produced than can survive.

Step-by-step explanation:

Natural selection occurs when there are differences in fitness among members of a population. As a result, some individuals pass more genes to the next generation. This causes allele frequencies to change.

The factors needed for natural selection to occur include:

1. Variation of traits among individuals: This is necessary because if all individuals in a population have the same traits, there would be no selection pressure for certain traits to be favored.
2. Competition for limited resources: When there is competition for resources like food, water, and territory, only those individuals with advantageous traits will have a higher chance of surviving and reproducing.
3. More offspring are produced than can survive: This increases competition and ensures that only the fittest individuals pass on their genes to the next generation.