Question

variation is useful for the survival of species over long time 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 happen due to inaccuracies in DNA copying.Thus new organisms with variations may have survival advantages and can adapt to the environment.as new generations come there is more accumulation of variations which help in survival of such species.Such species have better chances of survival For example,in a bacteria population,new variants are formed.if the temperature of water in which they live is increased,the bacteria tolerant to heat that is the variants will survive while the normal bacteria dies...