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bioRxiv · 10.64898/2026.05.20.726591

Demographic trade-offs decouple pollination services from plant population growth

Iler, A. M.·CaraDonna, P. J.·Petry, W. K.
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Abstract

Most plants require animal pollination to reproduce, prompting concern that pollinator declines immediately threaten plant populations. This concern is warranted if pollinator-mediated seed losses cause declines in plant population growth rates ({lambda}). However, demographic trade-offs might reduce the risk of population decline if seed loss improves performance elsewhere in the life cycle. We conducted a multi-year pollination manipulation on four species and measured how demographic vital rates and {lambda} responded. Seed responses did not predict net changes in {lambda}. Reduced pollination decreased seed production, but only caused a net decrease in {lambda} in one species; in the others, improved survival buffered {lambda}. Increased pollination boosted seed production, but at a cost to survival that caused a net reduction in {lambda} in three species. Our results highlight the importance of demographic trade-offs for understanding the impacts of pollinator declines on plant biodiversity and, more broadly, the population-level impacts of changing mutualisms.

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Iler, A. M., CaraDonna, P. J., Petry, W. K.. 2026-05-21. Demographic trade-offs decouple pollination services from plant population growth. https://doi.org/10.64898/2026.05.20.726591

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