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arXiv · 2609.34956

Models of Ecological Fitting

Rudy Arthur·Arwen Nicholson·David M Wilkinson
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Abstract

Ecological fitting describes a situation where species interact despite no shared evolutionary history. It is both a null model for adaptation and an important process in its own right, for example, the establishment of a non-native species is ecological fitting, and it is a major mechanism in the formation of Novel Ecosystems. In this paper we introduce and analyse a model of ecological fitting. We demonstrate both analytically and through simulation that the main factors determining invasion success are the invaded ecosystem's population and diversity, which set the size of the barrier for invaders. We also study the situation where many evolutionarily unrelated species simultaneously colonise an empty area. We show that a successful equilibrium is likely to be established, but the diversity tends to be very much less than the number of species in the starting pool and discuss the implications of this.

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Rudy Arthur, Arwen Nicholson, David M Wilkinson. 2026-09-28. Models of Ecological Fitting. https://arxiv.org/abs/2609.34956

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