What is your niche at school?
Are you on the basketball team? Are you a cheerleader? Do you play an instrument in the band? Your niche would be your role or place in the school. Organisms also each have their own niche in the ecosystem. Is an organism a producer or a consumer? How does the organism interact with other organisms? Is the organism involved in any symbiotic relationships?
Habitat and Niche
Each organism plays a particular role in its ecosystem. A niche is the role a species plays in the ecosystem. In other words, a niche is how an organism “makes a living.” A niche will include the organism's role in the flow of energy through the ecosystem. This involves how the organism gets its energy, which usually has to do with what an organism eats, and how the organism passes that energy through the ecosystem, which has to do with what eats the organism. An organism's niche also includes how the organism interacts with other organisms, and its role in recycling nutrients.
Once a niche is left vacant, other organisms can fill that position. For example when the Tarpan, a small wild horse found mainly in southern Russia, became extinct in the early 1900s, its niche was filled by a small horse breed, the Konik (Figure below).
The Konik horse. This horse filled the niche left by the Tarpan, a horse that became extinct in the early 1900s in southern Russia.
A species' niche must be specific to that species; no two species can fill the same niche. They can have very similar niches, which can overlap, but there must be distinct differences between any two niches. When plants and animals are introduced, either intentionally or by accident, into a new environment, they can occupy the existing niches of native organisms. Sometimes new species out-compete native species, and the native species may go extinct. They can then become a serious pest. For example, kudzu, a Japanese vine, was planted in the southeastern United States in the 1870s to help control soil loss. Kudzu had no natural predators, so it was able to out-compete native species of vine and take over their niches (Figure below).
Kudzu, a Japanese vine, introduced intentionally to the southeastern United States, has out-competed the native vegetation.
The habitat is the physical area where a species lives. Many factors are used to describe a habitat. The average amount of sunlight received each day, the range of annual temperatures, and average yearly rainfall can all describe a habitat. These and other abiotic factors will affect the kind of traits an organism must have in order to survive there. A habitat should not be confused with an ecosystem: the habitat is the actual place of the ecosystem, whereas the ecosystem includes both the biotic and abiotic factors in the habitat.
Santa Cruz Island off the California coast has diverse habitats including a coastline with steep cliffs, coves, gigantic caves, and sandy beaches.
The above image shows wetland reeds, another type of habitat.
Habitat destruction means what it sounds like—an organism's habitat is destroyed. Habitat destruction can cause a population to decrease. If bad enough, it can also cause species to go extinct. Clearing large areas of land for housing developments or businesses can cause habitat destruction. Poor fire management, pest and weed invasion, and storm damage can also destroy habitats. National parks, nature reserves, and other protected areas all preserve habitats.
abiotic factor: Aspect of the environment that is not a living organism, such as soil, water, or air.
biotic factor: Components of the environment that are living, or were alive and then died, such as plants or animals.
habitat : Natural home or environment of an organism; the physical environment in which a species lives.
niche: The role a species plays in the ecosystem.
- The role a species plays in the ecosystem is called its niche.
- A habitat is the physical environment in which a species lives.
Use the resource below to answer the questions that follow.
- Niches and relationships between organisms are generally developed over a long period of time. How do you think rapid changes in the chracteristics of niches affect the animals occupying that niche?
- Do you think rapid or gradual changes in niches have a greater potential to affect organisms? Think carefully and realize there may not be only one answer.
- On a very broad scale, how are the niches of a carnivore and an herbivore in the same geographic area similar? How do they differ?
- What is a niche?
- Name three factors that can be used to describe a habitat.