High floral disparity without pollinator shifts in buzz-bee-pollinated Melastomataceae

Author(s)
Constantin Kopper, Jürg Schönenberger, Agnes S. Dellinger
Abstract

Shifts among functional pollinator groups are commonly regarded as sources of floral morphological diversity (disparity) through the formation of distinct pollination syndromes. While pollination syndromes may be used for predicting pollinators, their predictive accuracy remains debated, and they are rarely used to test whether floral disparity is indeed associated with pollinator shifts. We apply classification models trained and validated on 44 functional floral traits across 252 species with empirical pollinator observations and then use the validated models to predict pollinators for 159 species lacking observations. In addition, we employ multivariate statistics and phylogenetic comparative analyses to test whether pollinator shifts are the main source of floral disparity in Melastomataceae. We find strong support for four well-differentiated pollination syndromes (‘buzz-bee’, ‘nectar-foraging vertebrate’, ‘food-body-foraging vertebrate’, ‘generalist’). While pollinator shifts add significantly to floral disparity, we find that the most species-rich ‘buzz-bee’ pollination syndrome is most disparate, indicating that high floral disparity may evolve without pollinator shifts. Also, relatively species-poor clades and geographic areas contributed substantially to total disparity. Finally, our results show that machine-learning approaches are a powerful tool for evaluating the predictive accuracy of the pollination syndrome concept as well as for predicting pollinators where observations are missing.

Organisation(s)
Department of Botany and Biodiversity Research
Journal
New Phytologist
Volume
242
Pages
2322-2337
No. of pages
16
ISSN
0028-646X
DOI
https://doi.org/10.1111/nph.19735
Publication date
2024
Peer reviewed
Yes
Austrian Fields of Science 2012
106008 Botany, 106012 Evolutionary research, 106042 Systematic botany
Keywords
ASJC Scopus subject areas
Physiology, Plant Science
Portal url
https://ucrisportal.univie.ac.at/en/publications/high-floral-disparity-without-pollinator-shifts-in-buzzbeepollinated-melastomataceae(2ca444b9-436c-45d8-bf63-b55dab78c71d).html