Question

How does the creation of variations in a species promote survival?

Answer 1

Organisms have to change themselves generation after generation. They can survive only if they adapt to the environment. Therefore, the existence of a species changes due to the emergence of variations and this occurs in sexual reproduction.

Answer 2

Sometimes for a species, the environmental conditions change so drastically that their survival becomes difficult. For example, if the temperature of water increases suddenly, most of the bacteria living in that water would die. Only few variants resistant to heat would be able to survive. If these variants were not there, then the entire species of bacteria would have been destroyed. Thus, these variants help in the survival of the species. 

However, not all variations are useful. Therefore, these are not necessarily beneficial for the individual organisms.

Answer 3

Natural selection selects the individuals with the aptest variations for their survival in the prevailing environmental conditions. Variant individuals that can adapt to the prevailing environmental conditions better have greater chances of surviving and producing offsprings.