Here's why:

* Food: Organisms need a source of nourishment to survive.

* Water: Water is essential for all living things.

* Shelter: Organisms need protection from predators, weather, and other environmental hazards.

* Space: Organisms require enough room to live, move, and reproduce.

While a habitat might support a dominant species, it will always host a variety of organisms, forming a complex ecosystem. A single species cannot define an entire habitat.