Solution

Variations are the raw material for evolution, favorable variation can increase the chances of survival of the species. It forms the basis of evolution e.g. If an organism can withstand a little higher temperature, then the variation goes on accumulating in its future generations. Hence, these organisms can survive when there is a sudden rise in the temperature. This ensures the survival of the species. But some other organisms (variants) without this variation of heat resistance may not survive due to sudden rise in temperature. So, variation is beneficial to the species, but not necessarily for individuals.