Ecological niche: what is it and how does it help to understand nature?

What is the ecological niche? Let's see what Biological phenomena are embodied in this concept.

Today, scientists theorize that there are an average of 7.77 million animal species in the world. there are an average of 7.77 million animal species in the world, of which 953,434 have already been catalogued.. From both a theoretical and practical point of view, there must be a certain order among each of the members encompassed in these figures, because the physical space on Earth is finite.

Ecology, a branch of biology that focuses its efforts and interest on the relationships of living beings with each other and with their environment, is in charge of discovering this "invisible" order to the human eye. From the prey-hunter relationship to the effects of climatic variables on organisms, this branch of science leaves nothing to chance in nature.

Today we come to show you a term as exciting as it is abstract, which is key to the understanding of ecology as a scientific discipline: the ecological niche. We assure you that, after reading these lines, you will never again see a walk in the countryside in the same way as before.

What is an ecological niche?

This abstract concept has undergone many conceptual modifications since it was coined in the early 20th century. Although many of its meanings are valid, in general the ecological niche can be defined as follows: "a multidimensional hypervolume that includes all biotic and abiotic factors with which the organism relates."

To present the term in a more reader-friendly way, even if we err on the side of reductionism, we can also generalize it by saying that the niche is the range of environmental, physical and biotic conditions (conditioned by the living beings) in which a species, or rather a population, can develop and endure over time successfully over time. The description of an ecological niche tries to explain, taking into account many variables, the reason for the adaptations of living beings to their environment and their viability in the short and long term.

Although this is a rather abstract term, several scientific publications have established certain bases in relation to it. We show you some of them in the following list:

• The niche must be understood in a functional sense, with function being understood as all organism-environment interaction. It cannot be confused with habitat.
• Organism-environment interactions can be quantified by means of records and experiments based on statistical inference.
• The concept of niche should not be based solely on direct observations.
• The niche is an attribute of the individuals of a population belonging to a particular community and ecosystem.
• The niche reports information at the individual level but this is not relevant: the aim is to understand the dynamics at the population level.

Thus, the niche allows us to directly relate the geographic space through the notion of an abstract multidimensional space composed of "n variables", where a species develops or potentially develops.where a species develops or potentially could do so. We know, all this conglomerate is a bit complex to understand, but in the following lines we assure you that everything will be clearer.

What does this term refer to in biology?

Intertwined with natural selection, the concept of niche allows us to postulate a clear but irrefutable reality, at least in a theoretical framework: two species competing for the same resources cannot coexist locally unless they occupy different niches.. Therefore, ecologically identical species cannot coexist in the same ecosystem, because one of them will be forcibly displaced or suffer extinction. Let's take a completely fictitious but functional example:

If we understand a resource such as food in a region along the X-axis of a graph, each of the "curves" drawn will represent the exploitation of that resource by a given species. It is in the "interest" of the animals to have as much distance as possible between the curves of different species, because if they overlap, intense competition will occur, which, in the long run, will not benefit the animals. competition that, in the long run, benefits no one.

Think, for example, of insectivorous birds and bats in a region. Both are flying, small in size and have the same diet: if both species coexisted in the same temporal space, the "resource exploitation curves" or their niches would be dangerously close, wouldn't they? Therefore, the solution may be a favoring of reproduction of nocturnal individuals in bat populations by natural selection.

Thus, bats would begin to exploit a nocturnal niche throughout their evolutionary history, with all the particularities and adaptations that this requires. While birds sleep, these winged mammals can develop so that, despite having similar needs, both species avoid overlapping. We do not want to say that this example is real, but it is certainly a "textbook" case that allows us to understand in a simple way what an ecological niche is.

Types of ecological niche

Once the term is clear, we should also point out that there are two main types of ecological niche: the realized and the fundamental.

The realized niche specifies the geographic range, based on the variables already described, that allows a population to develop at a practical level, i.e., the fundamental niche. at a practical level, i.e., the place where a population of a species actually inhabits at this time. Although it may seem that we are circumscribing the term to a "place", this is not so: we are still talking about an abstract term that does not refer to a fixed position.

On the other hand, the fundamental niche explores the places that a species could occupy in the absence of other competing species.. Thus, a fundamental niche becomes a realized niche when we take into account predator-prey interactions, disease, parasitism or competition for resources among living things. Perhaps a fish could live in the upper reaches of a river according to its biological adaptations, but a piscivorous species that has been evolving and successfully exploiting its niche for thousands of years may thrive there.

Acceptions of this term

Again, we want to emphasize that the concept of niche does not refer only to a physical place, however tempting it may seem to treat it as indistinguishable from a habitat. Below, we present a series of niche-based meanings that should be taken into account:

• Niche as habitat: early ideas of niche were based on the physical place that animals exploited and in which they developed.
• Niche as a role: other authors postulate that the niche is more conditioned by the trophic relationships between species than by the physical space itself.
• Niche as an "N-dimensional hypervolume": a quantitative description of the range of conditions that allow a population to persist somewhere.

Of course, the third meaning is the most widely accepted today. We are dealing with a combination of physical place and roleThe third meaning is, of course, the most widely accepted today, since climatic conditions as well as the food chain and other relationships with living things are equally important in predicting or knowing the range of a species' population.

Criticisms of this construct

To search for a scientific current or an idea free of criticism in the research community is a real chimera. The ecological niche could not be any different, as almost no postulation is untouchable today.

The difficulty in quantifying an exact ecological niche lies in the fact that, for each variable, how each variable affects the rate of population growth.. For example, if a species survives at X temperature, we would have to experiment in the laboratory with all possible environmental combinations that would allow its development in terms of this parameter. As you can imagine, this is practically impossible.

Even so, we want to make it clear that the operational difficulty in measuring a parameter does not detract from the value of its estimation at all. As is often said in the scientific community, in many cases it is better to approximate than not to know anything at all. it is better to approximate than to know nothing and, sometimes, recording uncertainty or assaying negatives is as important as any other discovery..

Summary

As you will have seen in these lines, the ecological niche is a complex, abstract term with multiple meanings. If we want something to be clear after reading this space, it is the following: the niche is the set of all the parameters you can think of that make a population to be present in a specific place and not in another. So complex, so simple.

The next time you walk through the countryside, ask yourself why that beautiful bird flies higher than another or why one insect lives on the leaves and another under the stones. Each living thing occupies its space and specializes in it: in the niches lies the key to the arrangement of life in nature.

Bibliographical references:

• About the concept of ecological niche, repository.geotech.edu. Retrieved 18 November from http://repositorio.geotech.cu/jspui/bitstream/1234/2938/1/Acerca%20del%20concepto%20de%20nicho%20ecol%C3%B3gico.pdf
• Ecological niche, web.ecología.unam. Retrieved November 18 from http://web.ecologia.unam.mx/oikos3.0/index.php/articulos/tuxtlas/17-recuadros/376-nicho-ecologico.
• A brief introduction to ecological niche models, researchegate.net. Retrieved 18 November from https://www.researchgate.net/publication/339181920_Una_breve_introduccion_a_los_modelos_de_nicho_ecologico.