Describe the difference between habitat and niche.

A habitat is the physical environment where an organism lives, while a niche refers to the role an organism plays in that environment.

A habitat is essentially the address of an organism, it's the physical location where it lives. This could be as broad as a forest or as specific as the bark of a tree. Habitats can be identified by their physical features, such as temperature, light levels, humidity, and the presence of certain types of vegetation or other species. For example, a polar bear's habitat is the Arctic, characterised by its cold temperatures and presence of sea ice.

On the other hand, a niche is more like the job description of an organism. It describes how an organism fits into its environment and includes everything that affects its survival and reproduction. This includes the food it eats, when and how it gathers its food, where it finds shelter, its predators, and how it reproduces. For instance, the niche of a honey bee includes gathering nectar from flowers to make honey, pollinating flowers in the process, and living in a hive.

While multiple species can share a habitat, each species has its own unique niche. This concept is known as the competitive exclusion principle, which states that no two species can occupy the same niche in the same habitat at the same time. For example, in a forest habitat, a squirrel and a rabbit may share the same space, but they have different niches. The squirrel's niche might involve gathering and storing nuts, living in trees, and avoiding predators by climbing or jumping, while the rabbit's niche might involve eating grass and burrowing in the ground for shelter.

In summary, while habitat and niche are both crucial concepts in ecology, they refer to different aspects of an organism's existence. The habitat is the physical space an organism occupies, while the niche is the role an organism plays within its habitat, encompassing its interactions with the biotic and abiotic factors in its environment.