Misconceived experiments may yield valuable insights: Simulated florivory has unpredictable consequences for plant reproduction in Knautia arvensis (Caprifoliaceae)

Jeff Ollerton; Xin Xu; Zong-Xin Ren

doi:10.26786/1920-7603(2026)866

Authors

Jeff Ollerton University of Northampton, UK https://orcid.org/0000-0002-0887-8235
Xin Xu Kunming Institute of Botany https://orcid.org/0000-0002-8775-9508
Zong-Xin Ren Kunming Institute of Botany https://orcid.org/0000-0001-7265-065X

DOI:

https://doi.org/10.26786/1920-7603(2026)866

Keywords:

bumblebees, butterflies, Lepidoptera, hoverflies, pollinators, pollination, reproductive allocation

Abstract

An experimental manipulation of ray florets in Knautia arvensis (Caprifoliaceae) carried out in 2001 originally yielded results that were hard to reconcile with a hypothesis about floral attraction. Reframed as a test of florivory the archived data reveal that cutting ray florets left pollinator visitation and seed set essentially unchanged, but altered plant resource economics. Nectar concentration (and consequently available sugar after accounting for volume) declined under the large cutting treatment, while individual seed weight was consistently lower in the cut inflorescences. Together, these patterns suggest that simulated florivory can leave pollination largely intact yet reduce nectar quality and seed provisioning, producing lighter seeds without reducing seed set. More broadly, the study shows how re-examining archived “inconclusive” experiments through alternative perspectives can generate new ecological insights beyond those originally sought.

Author Biography

Jeff Ollerton, University of Northampton, UK

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