2.5a - parasitic niche

• an ecological niche is a multi-dimensional summary of tolerances and requirements of a species
• a species has a fundamental niche that it occupies in the absence of any interspecific competition
• a realised niche is occupied in response to interspecific competition
• as a result of interspecific competition, competitive exclusion can occur, where the niches of two species are so similar, one declines to local extinction
• where the realised niches are sufficiently different, potential competitors can co-exist by resource partitioning in which resources are split between potential competitors