question_answer 83)

  In an aquarium two herbivorous species of fish are Living together and feeding on phyto planktons. As per the Cause's principle, one of the species is to be eliminated in due course of time, but both are surviving well in the aquarium. Give possible reasons.

Answer:

                  Competition is a rivalry relationship between two or more organisms. A competition between individual of same species (intra specific) is more acute than the competition between individual of different species as all the members in a interspecific competition have same basic requirements like food, water, light, space, mating and shelter. But this is true only when resources are limited. According to Cause's principle, one of the species is to be eliminated. But studies recently have revealed that species facing intra specific competition may evolve mechanism to pencourage co-existence rather than exclusion. This can also be done by a method known as ' resource partitioning'.