Final answer:
A niche in biology is the role and position a species occupies within its ecosystem, encompassing interactions with biotic and abiotic factors, its source of energy and nutrients, feeding behaviors, and its habitat. The habitat is the specific physical environment where a species lives. No two species can occupy the same niche indefinitely due to the competitive exclusion principle.
Step-by-step explanation:
A niche in an ecosystem is crucial in understanding the role and position a species occupies within its environment. The term refers to the sum of all interactions that a species has with both the living (biotic) and non-living (abiotic) components of its ecosystem. This includes what the species eats (source of energy), how it obtains its food (foraging behaviors), how it competes with other species, and its role in nutrient recycling within the ecosystem. Additionally, a niche encompasses how an organism interacts within symbiotic relationships and its overall contribution to the flow of energy through the ecosystem.
Another critical part of a species' niche is the habitat, which is the physical location where a species lives and to which it has adapted. Habitats are influenced by abiotic factors such as temperature and rainfall and can range from very specific to quite general, depending on the species' needs and adaptations.
It is important to note that no two species can occupy the exact same niche within an ecosystem for an extended period due to the competitive exclusion principle. This principle states that two species competing for the same resources cannot coexist at constant population values if other ecological factors remain constant.