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bioRxiv · 10.1101/2020.08.25.263806

Hidden layers of density dependence in consumer feeding rates

Stouffer, D. B.·Novak, M.
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Abstract

Functional responses relate a consumers feeding rates to variation in its abiotic and biotic environment, providing insight into consumer behavior and fitness, and underpinning population and food-web dynamics. Despite their broad relevance and long-standing history, we show here that the types of density dependence found in classic resource- and consumer-dependent functional-response models equate to strong and often untenable assumptions about the independence of processes underlying feeding rates. We first demonstrate mathematically how to quantify non-independence between feeding and consumer interference and between feeding on multiple resources. We then analyze two large collections of functional-response datasets to show that non-independence is pervasive and borne out in previously-hidden forms of density dependence. Our results provide a new lens through which to view variation in consumer feeding rates and disentangle the biological underpinnings of species interactions in multi-species contexts.

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Stouffer, D. B., Novak, M.. 2020-08-25. Hidden layers of density dependence in consumer feeding rates. https://doi.org/10.1101/2020.08.25.263806

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