Difference Between Fundamental and Realized Niche
‘Niche’ is a French word which means ‘a nest’. The term was used by a naturalist named Grinnell in 1917 for the first time to describe the habitat of a species. Niche refers to the sum total of the natural requirements necessary for meting and producing offspring. A niche is necessary for survival of species. A fundamental niche refers to the natural habitat of a species while a realized niche refers to many factors like presence of predators, human activities and availability of natural resources etc. Let us discuss differences between the realized niche and fundamental niche.
A rat is an omnivore. It can eat anything. It is called the fundamental niche of a rat. But they are unable to eat anything because there is presence of predators like cats and human does not like them in their homes. So, a rat’s food become limited and cannot eat whatever he likes. He has to eat what he gets. This is a realized niche for the rat. This principle applies to all the animals.
Favorable environmental conditions and adaptation to the environment are necessary for a species to survive, mate and reproduce. A species requires the ability to save itself from predators and to have food for energy. If all the requirements of a species to survive are present in environment, it is called fundamental niche of that species. These are natural conditions and desirable. On the other hand realized niche comprised ecological conditions actually present. In this way, fundamental niche is desirable and realized niche is real.
In fundamental niche, a species need not worry about food and predators. It provides an ideal and safe environment to the species in which he can mate, reproduce and survive easily. He need not have to adapt much. A raccoon lives in the forest where he gets plenty of food like bugs, insects and fruits to meet its energy requirements. He can easily hide itself from the predators. But as a result of changing ecological conditions, he is forced to live in a realized niche. It is force to live in urban settings where he finds garbage to eat than its natural food.