Question

___________ are useful for survival of species.

Answer 1

Variations:

1. Reproduction is a biological process in which new individuals are produced from the existing ones.
2. If reproduction does not occur, the number of organisms in a population will keep on decreasing and ultimately the species will become extinct.
3. Sexual reproduction is the mode of reproduction where fusion of male and female gametes occur resulting in offspring who differ from either of the parents and from each other too.
4. So sexual reproduction results in variation in the offspring.
5. Natural selection is a process of better adaptation of an organism to a changing environment.
6. This leads to evolution.
7. Natural selection will act on this variation and either the variation will remain in the population or will gradually disappear.
8. So the variation maintained in the population helps the individuals to survive and adapt in a better way to the surroundings.

Final answer: Variations are useful for survival of species..