Environmental or ecological niche defines the relational position of a particular species in a given ecosystem or environment. It includes both the biotic and abiotic factors and how they interact with the species. The biotic factors may include the food and predators, and how the organism behave in their abundance or scarcity. For example, if food is in abundance and predators are less, species population will grow rapidly. Similarly, how abiotic factors such as climate affect the organism is also part of the niche.
The variables or factors that comprise the niche vary from species to species. And no two species can occupy the same ecological or environmental niche for too long, ultimately one species will outcompete the other species.
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