Question

Variation is useful for the survival of species overtime but the variants have unequal chances of survival.Explain this statement

Answer 1

overproduction of offsprings by organisms will lead to limited resources which will further lead to struggle for existance.during this time,some variations are found each species which may be favourable or unfavourable.the organisms with favourable variations survive and sustain the species whereas the organisms with unfavourable variations get eliminated.this is why it is said that variation is useful for the survival of species over long time but the variants have unequal chances of survival. 

Answer 2

Variations are beneficial to the species than individual because sometimes for a species, the environmental conditions change so drastically that their survival becomes difficult. For example, if the temperature of water increases suddenly, then most of the bacteria living in that water would die. Only few variants that are resistant to heat would be able to survive. However, 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, all variations are not necessarily beneficial for the individual organisms.