Ecologists have to deal with different types of organisms: from cyanobacteria to elephants. It is clear that the habitats in this case can be very different. The methods of study are also different. How can one investigate such diverse phenomena? Is it possible to identify patterns in this way? Yes, there is a special scientific toolkit, which is based on the concept of "ecological niche." Any branch of the science under discussion deals with this concept. So, let's figure out what it is.
The term itself was proposed a very long time ago, in the 20s of the 20th century. He was invented by the representative of a practical nation - American John Greenll. In his understanding, the "ecological niche" is the conditions normal for the habitat of one or another species. But Charles Elton, a Briton, formulated it, specifying, in a different way. He said that a niche is a relationship with food and a relationship with natural enemies. There are two different approaches to the definition. In the first case, it means “address” (where he lives), in the second - “profession” (what he does in the community). But two different species may have the same function in different communities. For example, in Russia, large herbivores are moose, in Africa - antelopes, in Australia - kangaroos.
The Americans did not have such a broad definition of the concept of "ecological niche." Therefore, in the 50s, a scientist from this state, George Hutchinson, created a multidimensional model. Under the term, he proposed to consider the entire range of environmental factors in which the species lives. And for a long time. And be sure to multiply. Let's take an example of some kind of plant. Let us know that there are upper and lower limits of temperature in which a given species can live and feel good. This data can be represented as a coordinate system in which temperature can be plotted along one of the axes. And the second axis will be humidity, the third, for example, the amount of nutrients. As a result, the graph will become a voluminous figure, like a box.
Using this model, Hutchinson compared niches of different species of organisms. Imagine several such boxes in space. This allows you to visually show some of the relationships of animals in space and their competition for food. For animals, the following axial indicators are usually used: spatial location, nutrition, and seasonality.
Some species are omnivorous and live in different places, and some eat monotonous food and live in strictly defined conditions. The more nutritional options, the more ecologists say about the greater “niche width”. Say, a koala loves only eucalyptus leaves (and not all species), and possums eat almost everything. Is it good when the ecological niche is wide? On the one hand, yes, because it allows you to adapt to environmental changes. But if the environment is stable, then the situation is more favorable for species eating one type of food. In addition, those who love diversity are usually less able to get food than "narrow specialists."
Many species with similar niches have to compete fiercely for food. Therefore, almost never two species with similar niches in one community do not live geographically, one inevitably replaces the second. This was established experimentally by a scientist from Russia, Gauze. It turns out that herbivores of one territorial community eat different plants. And different predators prey on completely different species of prey.
Often the niches overlap partially, but the nutrition of organisms must be different. Of course, for the normal functioning of the community, niches should overlap in some respects, but there must always be room for flexibility, otherwise the mind is almost impossible to survive.
The human ecological niche is the widest and most extensive. We need to ensure that next to us there is also a space for the existence of other species. Nature does not tolerate neglect.