Niche Construction - Examples

Examples

• Earthworms: Through a process of modification, earthworms chemically alter the soil in which they live. This change in soil chemistry stimulates an increased fitness in earthworm populations. The subsequent chemical composition of soil produced by earthworm activity also benefits the growth of proximal species of plants and other biota present in the soil.
• Lemon Ants (Myrmelachista schumanni): This species of ants employs a specialized method of suppression that regulates the growth of certain trees. Lemon ants make their homes in the bodies of Duroia hirsuta, a species of tree found in the Amazonian rainforest of Peru. To ensure the prevalence of Duroia trees, Lemon ants employ self-derived quantities of formic acid (a chemical fairly common among species of ants) as a tenacious herbicide. The end result alters the composition of their forest habitat drastically by wiping out arboreal species ill-suited for colony habitation. When observed by humans, the subsequent altered ecologies perpetuated by these ants have been termed the Devil's Gardens.
• Leafcutter Ants (Atta): Leaf cutter ants, related distantly to the Lemon Ants, also share a relationship with plants that makes their niche unique. Native to the tropical regions of the North and South America, this species harvests foliage from surrounding broadleaf plants outside their nests and drag them down to specialized chambers. In these chambers, the leaves are used as source of nutrition for a family of fungi known as Lepiotaceae. They form a symbiotic relationship with the fungus: the ants feed and groom the fungus, keeping it safe from pests, and in turn the fungus provides food for the queen and other members of the colony. There are currently sixteen individual species recognized by scientists, and are the only species known to occupy this niche.
• Beavers: In the construction of their dams, beavers drastically shape and alter the ecosystem in which they live. Deforestation, effects on soil structure, root structure, turbidity of water, allocation of water and the supply of water downstream are just a handful of exemplars defining beaver niche construction. Beavers express a clear example of the diverse effects perpetuated by the construction of a niche. In the mammalian kingdom beavers are one of the greatest proximal modifiers.
• Diatoms in the Bay of Fundy, Canada, provide another example of an ecosystem engineer. Benthic diatoms living in estuarine sediments secrete carbohydrate exudates that bind the sand and stabilize the environment. The diatoms cause a physical state change in the properties of the sand that allows other organisms to colonize the area. The concept of ecosystem engineering brings new conceptual implications for the discipline of conservation biology.
• Pine Trees & Chaparrals: Chaparrals and pines have been found to express niche constructing behavior in response to the effects of forest fire. These trees and shrubs increase the frequency of fire by affecting the composition of the forest floor. They achieve this end through the dispersal of needles, cones, seeds and oils, essentially littering the forest floor. The benefit of this activity is compounded by an adaptation in these particular flora that has selected for a resistance to fire. The evolutionary exchange (made between both niche construction and natural selection) allows the fire-resistant pine and chaparral to exploit the chemical change that occurs in soil after organic matter has been burned.
• Humans: See subsection below.