Species compete with other species for the same resources. But what if there was no competition? How would a given species fare? Learn about the concept of the fundamental niche.
What is a Fundamental Niche?
Every species has a role that it plays in nature. That role is defined by a combination of the organism’s behaviors, habitat, and interaction with other species. For example, a garden spider is a predator that hunts for prey among plants, while an oak tree grows to dominate a forest canopy, turning sunlight into food.
The role that a species plays is called its ecological niche.A niche includes more than what an organism eats or where it lives. Environmental factors, such as climate, soil chemistry, and elevation, also play a role in defining a niche.Sometimes other species will compete for the same niche. Lions on the African savanna compete with hyenas for food. Daisies and dandelions in a field compete for sunlight and soil. Competition from other species for the same niche is called interspecific competition.
In order to better understand an organism, ecologists try to determine what sort of niche it would have in the absence of such competition. They might ask, ‘How would a lion behave if there were no other predators competing for a zebra’s flesh?’ or ‘What would a stand of water lilies look like if there was no duckweed living in the same area of the pond?’ A fundamental niche is the term for what an organism’s niche would be in the absence of competition from other species.Generally, however, there are competitors for the same lifestyle.
Rabbits compete with groundhogs for food. Grasses compete with shrubs for soil, and bacteria compete with mold for nutrients among the leaf litter. The niche that a species actually inhabits, taking into account interspecific competition, is its realized niche.
Examples of Fundamental Niches
The male red-winged blackbird’s mating call can be heard in the marshes in early spring.
At that time, they hold the prime real estate in the marsh. However, as the season progresses, the more aggressive tri-color blackbirds move in. The tri-colors take over the best territory and force the red-wings to choose the leftovers. The entire marsh represents the red-winged blackbirds’ fundamental niche.
Spartina alterniflora is a grass species that is very tolerant of salt. It lives in salt marshes along the eastern North American coast. These marshes go underwater at high tide. While it is found all along the coast, it does not live in nearby freshwater environments.From this observation, one might conclude that S. alterniflora cannot tolerate fresh water.
This is not so. If given a chance, it grows even better in fresh water than in salt. However, the freshwater environments are inhabited by aggressive plant species that are very well adapted to the habitat. Spartina alterniflora cannot compete. In other words, while S. alterniflora is only found in salt marshes, its fundamental niche includes freshwater habitats as well.
Remember that only organisms competing for the same niche (or a very similar one) count in terms of this concept. While a mouse certainly competes with an owl by trying to avoid becoming lunch, the owl and the mouse do not make a living in the same manner. A different species of mouse trying to live in the same holes and eat the same food would, in fact, present the sort of interspecific competition that would interfere with the mouse’s fundamental niche.
Let’s review.Every species has a role that it plays in nature, defined by a combination of the organism’s behaviors, habitat, and interaction with other species. The role that a species plays is called its ecological niche, which not only includes what it eats and where it lives, but also environmental factors like climate, soil chemistry, and elevation.
Some other species will compete for the same niche. This competition from other species for the same niche is called interspecific competition. The niche that a species actually inhabits, taking into account interspecific competition, is its realized niche.But in order to better understand an organism, ecologists try to determine what sort of niche it would have in the absence of such competition. A fundamental niche is thus the term for what an organism’s niche would be in the absence of competition from other species.
As you learn about the fundamental niche, you’ll develop your ability to:
- Distinguish between ecological, fundamental, realized niches
- Determine a species’ fundamental niche
- Cite examples of fundamental niches