Exclusion of competition principle

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The competitive exclusion principle is a concept of theoretical biology developed by Georgi Franzewitsch Gause , which is used in ecology and evolutionary biology . The term means that two species cannot simultaneously occupy the identical ecological niche without entering into competition through which only the more competitive can ultimately assert itself. A universal validity of this principle is called into question by the plankton paradox .

Avoidance of competition principle

The positive reversal of this principle is the avoidance of competition . For the less competitive species in each case, evasion is essential to secure the ability to reproduce. This evasive movement can take place through spatial separation , temporal disentanglement (for example day and night activity ), an adaptation of eating habits and also an evolutionary adaptation , for example in the form of adaptive radiation .

General formulation

The competition between two species is written in the general form as

For a fixed point of this system the Jacobi matrix results in:

Because of the effects of intraspecific competition, the trace is <0. So a fixed point can only be used for

be stable.

Since this can be fulfilled in the general case, the principle of exclusion of competition does not apply in several models, such as variants of the Lotka-Volterra equations .

However, narrower models lead to the exclusion of competitors. For example, assuming that two species are fighting for a single resource and that resource is given as a function of the species, a model of form is obtained

is the resource function. Further, here is the recovery rate of species , the recovery rate of species , the death rate of species, and the death rate of species . All of these constants are positive. It follows

where is a constant here. If you write and , you get

Integration leads to . Under the biologically meaningful assumption that both x and y are restricted and the additional assumption that it is not zero, this leads to the extinction of one of the two populations.

This consideration can also be applied to more than two species, since in this case one makes use of the pairwise exponential dependence of two populations each.

Transferability

In the sense of bionics , this principle can also be applied to economics . Analogous considerations help to develop strategies that can initially ensure the survival of competing companies.

literature

Individual evidence

  1. Jens Boenigk, Sabina Wodniok: Biodiversity and Earth History . Springer, 2014, ISBN 978-3-642-55388-2 , p. 180.