Skip to main content
Dryad

Data for: Environmental gradualism explains variation in pollination systems of columnar cacti: Phylogenetic and trait evolution analyses

Cite this dataset

Freilij, Damián et al. (2023). Data for: Environmental gradualism explains variation in pollination systems of columnar cacti: Phylogenetic and trait evolution analyses [Dataset]. Dryad. https://doi.org/10.5061/dryad.02v6wwq74

Abstract

Aim: The Geographic Dichotomy Hypothesis (GDH) states several flowering plant groups have specialized pollination systems in tropical areas, where resources are more reliable and pollinator communities tend to be more stable. Our main goal was to understand the scope of the GDH and/or gradual environmental variation considering the evolutionary history of the pollination traits.

Location: Neotropical tropics and adjacent extra-tropics.

Major taxa studied: Columnar cacti.

Methods: Using a database composed of ~54 columnar cacti species (31.7% of the global columnar cactus species), four complex traits were analyzed: pollination syndromes, reproductive systems, type of anthesis, and duration of anthesis. We applied GLMs, phylogenetic regressions, evolutionary trait optimization, and multivariate models with 19 bioclimatic variables and potential evapotranspiration.

Results: Weak phylogenetic signal was detected for all traits, giving consistent results between GLMs and phylogenetic regression analysis. The pollination syndrome and duration of anthesis varied with latitude, in contrast to the reproductive system and the type of anthesis. In the Southern Hemisphere, the pollinators were more diverse and the duration of anthesis was longer. Different evolutionary paths between hemispheres were detected and optimization showed a complex pattern in the evolution of traits, suggesting high homoplasy with multiple transformations by convergence and/or parallelism. The environmental models showed thermic seasonality may be at the core of the latitudinal variation of the pollination system.

Main conclusions: We did not detect a geographical dichotomy in pollination systems of the cacti, but rather a gradual change in different pollination attributes. Therefore, instead of a GDH, we propose an environmental gradient hypothesis (EGH). Environmental variables may be explaining the variation detected in pollination system traits by conditioning floral properties (morphology, phenology), diversity and distribution of pollinators, and/or coevolution occurrence. The complexity implied in these traits is consistent with high homoplasy levels and a differential evolutionary history between the hemispheres.

Funding

International Foundation for Science, Award: D-4244-1

University of Buenos Aires, Award: 20020190200106BA

Agencia Nacional de Promoción de la Investigación, el Desarrollo Tecnológico y la Innovación, Award: 2020-1402