Answer :
A niche is the role an organism plays in an ecosystem or community. An organisms niche also includes its place in the food web, it's need for space, water, shelter, sunlight etc. If there are more organisms with the same niche, then competition for these factors will increase :-)
The niche of an organism refers to the parameters that describes all the requirements that a living organism needs to exist successfully in a particular ecosystem, these include both the abiotic and biotic factors in the concerned ecosystem. Every living organism has its own fundamental niche, which refers to all the possibilities that is open to that organism in that particular ecosystem. Overlapping niche occurs when there are too many organisms in an ecosystem that share the same niche. Overlapping niche usually leads to competition because the resources available are too small compare to the number of organisms that need them.
