What is Ecological Niche?
In ecology, a niche is the role or task of a species in a habitat. The word niche comes from the French word nicher, which means “to nest”. An ecological niche describes how a species interacts with and lives in its habitat.
Ecological niches have specific characteristics, such as the availability of nutrients, temperature, terrain, sunlight, and predators that determine how and how well a species survives and reproduces.
A species creates a niche for itself in a habitat in that it can adapt and deviate from other species. Modern ecologists study ecological niches in terms of the effects of the species on their environment, as well as the requirements of the species.
According to the principle of exclusion of competition, two species cannot occupy the same ecological niche in a habitat if they compete for the same resources. When species compete in a niche, natural selection will initially reduce the species’ dependence on the shared resources.
When one species is successful, it reduces competition. If neither evolves to reduce competition, the species that can use the resource more efficiently will win, and the other species will eventually become extinct.
Examples of Ecological Niches
Kirtland’s Warbler is a rare bird that lives in small areas on Michigan’s northern Lower and Upper Peninsula. Kirtland’s Warbler niche is the Jack Pine forest, and the forest must have very special conditions.
Jack pine forests of over 80 acres are ideal for this species. Specifically, these forests must have dense clumps of trees with small patches of grass, ferns, and small shrubs in between. Kirtland’s warbler nests on the ground under the branches when the tree is about 5 feet tall or about 5-8 years old. When the tree reaches 16 to 20 feet in height, the lower branches begin to die, and the bird no longer nests under the branches.
Jack pine forests remained virtually undisturbed during Michigan’s lumber boom in the early 1800s because white pine was a much more valuable. The consistent availability of young jack pines for nesting was generated by naturally occurring wildfires in this habitat. When the lumber boom ended in the late 1800s, the wildfires continued and allowed the jack pine to spread and create more habitat for Kirtland’s warbler. The species population reached its peak from 1885-1900. Humans began to alter this niche by fighting and putting out forest fires. Over time, this severely affected the Kirtland’s warbler population. Large areas of jack pine forest were designated for habitat management via logging, burning, seeding and replanting in the 1970s, and the species recovered.
Jack pine forests were virtually undisturbed during Michigan’s wood boom in the early 19th century as white pine was far more valuable. The constant availability of young Jack Pines to breed was created by naturally occurring forest fires in this habitat.
When the wood boom ended in the late 19th century, the forest fires continued, allowing the Jack Pine to spread and create more habitat for Kirtland’s warblers. The species population peaked from 1885 to 1900.
People began to change this niche by fighting and putting out forest fires. Over time, this had a serious impact on the warbler population in Kirtland. In the 1970s, large areas of the Jack Pine forest were designated for habitat management through logging, burning, sowing and replanting, and the species were recovering.
As the name suggests, dung beetles eat dung, both as adults and as larvae. They live on all continents except Antarctica. Manure is abundant around the world and over time the dung beetle has learned to use it as a resource and create its own niche.
Dung beetles are known for rolling dung into a ball before shipping. These balls are buried in an underground burrow to either be stored as food or used as breeding balls. The female lays eggs in the broodball and the larvae hatch inside.
When they grow up, the beetles dig out of the sphere and work their way to the surface of the ground. The effects of dung beetles fulfill several important functions in their habitat. Digging caves and tunnels turns around and aerates the soil.
The buried manure releases nutrients into the soil that benefit other organisms. In addition, the beetle’s use of manure leaves is less available to flies, which allows some of the fly population to be controlled.
Xerophytic plants have developed various adaptations to life in arid ecological niches. The adjustments were developed to save the water stored in the system and to avoid water loss. Examples of xerophytes are cacti and aloe vera, also called succulents.
These plants have thick fleshy leaves that hold water and long roots to reach water deep underground. Other adaptations xerophytic plants use include the ability to move or fold their leaves, drop their leaves during periods of drought, a waxy coating to prevent evapo ration (called cuticles), and thick hairy leaf coverings.
The surface of the plant leaves has stomata, tiny mouth-like structures that absorb carbon dioxide and release oxygen and water. Plants usually open their stomata during the day and close them at night. Succulents do the opposite to reduce water loss during the heat of the day.
Organisms can create ecological niches in some of the most inhospitable places on earth. Extremophiles are organisms, primarily eukaryotes, adapted to and thriving in areas of environmental extremes.
The suffix -phile comes from the Greek word philos, which means loving. The type of extreme environment describes these organisms. Some examples are acidophiles (best growth between pH 1 and pH 5), thermophiles (best growth between 140°F and 176°F), barophiles (best growth at high pressures) and endolithic (growing within rock).
Some organisms, called polyextremophiles, have adapted to more than one extreme. The study of extremophiles is important to the understanding of how life originated on earth and what life could be like in other worlds. Extremophiles are also important in biotechnology because their enzymes (called extremozymes) are used under extreme production conditions.