Huge species diversity in nature gives rise to a variety of types of relationships between organisms. Living beings cannot escape the negative impact of nearby species. At the same time, the course of evolution contributed to the formation of diverse adaptations of living organisms to the environment. The environment means not only the world of inanimate nature, but also all living organisms nearby.
Companionship as a form of commensalism
One of the types of interaction between organisms is commensalism. In commensalism, one organism benefits from another, while the second species does not suffer from the first.
There are at least three types of commensalism:
1. Companionship.
2. Freeloading.
3. Cohabitation.
Fellowship in Biology
There are many examples of this type of commensalism. However, they should be distinguished from manifestations of freeloading. The very word"commensalism" comes from the Latin and translates as "together at the table." This description of the concept best characterizes the process of companionship. Because it is under him that different types of organisms eat side by side, as if at the same table.
When parasitizing, one type of organism waits until the other is full, only then proceeds to feed on the same resource.
Cohabitation is characterized by having a common place of residence. At the same time, one organism lives in the shelter of another.
Examples of companionship in nature
What is companionship? This is the process of obtaining food by different types of organisms from a common resource. Examples of companionship prove the complete absence of competition in this type of relationship. The fact is that such species feed on different parts of the resource or consume different substances from one part of the edible object.
A good example of companionship in nature is the relationship between bacteria and higher plants. Many types of bacteria feed on decaying vegetation. It is these saprophyte bacteria that completely decompose inanimate plant matter to a mineral substance. Higher plants, as you know, need ready-made mineral s alts for nutrition. All higher plants can grow only on those parts of the earth's surface where saprophyte bacteria function.
Legumes and cereals
Another example of companionship in the plant world is the commensalism of legumes and grains. Plants of the cereal familynormal growth and development need to consume a certain amount of nitrogen. The atmosphere contains a huge amount of this element, but cereals are not able to absorb it from the air. Plants in the legume family fix nitrogen on their roots. Cereals use the element ready for assimilation. The photo shows nodules of legumes.
Thus, legumes and cereals should be "at the same table" for full development. However, if leguminous plants become abundant, then competition arises among commensals. Legumes begin to shade and displace grasses.
Adult insect and caterpillar
There are countless examples of animal companionship. They are based on the fact that different species or stages of development of animals feed on one plant, but prefer different parts of it. So, if a bee or a two-winged insect prefers nectar, then the caterpillar eats the leaves of the same nectar plant.
Biotopes of different warbler species
Birds tend to live in certain areas of the territory, as well as at a certain height (tiers) of the forest. The genus of warblers living in central Russia includes the following species: gray warbler, garden, hawk, hawk, blackhead. While the hawk-warbler forages on the ground and in the lower layer of the forest, the blackhead and the hawk feed on the top of the tree crowns. The gray warbler prefers the second and third tiers of the forest, that is, the middle part of tree crowns.breeds.
From Neutralism to Mutualism
According to evolutionary scientists, companionship is a transitional link from neutralism to mutualism (obligate coexistence). The example of the companionship of legumes and cereals proves such a position of scientists. For many years of evolution, higher plants have not adapted to absorb nitrogen from the atmosphere on their own. This chemical element, ready for assimilation, is provided to them by leguminous plants. But legumes themselves are also not capable of fixing nitrogen on their own. This work is done for them by nitrogen-fixing bacteria that live on the roots.
Thus, the companionship of cereal grasses and leguminous plants, as well as the companionship of legumes and nitrogen-fixing microorganisms, is close to obligatory relationships. Because nitrogen is one of the main chemical elements of plants, especially legumes. And its content in the soil is extremely small.
Examples of companionship prove the presence of harmony in the biosphere. In the course of evolution, individual species adapted to specific environmental conditions, which led to the integrity of the system of the world of wildlife.
