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arXiv · 2603.17754

Slow evolution towards generalism in a model of variable dietary range

Elliot M. Butterworth·Tim Rogers
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Abstract

Species sharing a habitat will co-evolve to make use of the available resources, as consumption is modulated by competition and negative feedback loops between consumers and resources. The dietary range of a given species determines the resources it has access to and thus the other species with which it competes. A narrow dietary range avoids competition at the cost of over-reliance on a small selection of resources; conversely a wide dietary range provides more alternatives but also more chance of competition with other species. Here, we investigate the evolution of dietary range within a mathematical model of niche formation. We find highly path dependent co-evolution dynamics characterised by long-lived quasi-stable states. Ultimately, stochastic effects drive the evolution of generalist diets, as we uncover in our analysis and simulations.

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Elliot M. Butterworth, Tim Rogers. 2026-03-18. Slow evolution towards generalism in a model of variable dietary range. https://arxiv.org/abs/2603.17754

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