Global patterns and a latitudinal gradient of flower disparity: perspectives from the angiosperm order Ericales

Marion Chartier, Anna Maria Louise von Balthazar-Schönenberger, Susanne Sontag, Stefan Löfstrand, Thomas Palme, Florian Jabbour, Hervé Sauquet, Jürg Schönenberger

Morphological diversity (disparity) is an essential but often neglected aspect of biodiversity. Hence, it seems timely and promising to re-emphasize morphology in modern evolutionary studies. Disparity is a good proxy for the diversity of functions and interactions with the environment of a group of taxa. In addition, geographical and ecological patterns of disparity are crucial to understand organismal evolution and to guide biodiversity conservation efforts.
Here, we analyse floral disparity across latitudinal intervals, growth forms, climate types, types of habitats, and regions for a large and representative sample of the angiosperm order Ericales.
We find a latitudinal gradient of floral disparity and a decoupling of disparity from species richness. Other factors investigated are intercorrelated, and we find the highest disparity for tropical trees growing in African and South American forests.
Explanations for the latitudinal gradient of floral disparity may involve the release of abiotic constraints and the increase of biotic interactions towards tropical latitudes, allowing tropical lineages to explore a broader area of the floral morphospace. Our study confirms the relevance of biodiversity parameters other than species richness and is consistent with the importance of species interactions in the tropics, in particular with respect to angiosperm flowers and their pollinators.

Department of Botany and Biodiversity Research
External organisation(s)
CNRS - Muséum national d'Histoire naturelle UMR 7209, Royal Botanic Gardens and Domain Trust Sydney, Universität Wien, University of New South Wales
New Phytologist
No. of pages
Publication date
Peer reviewed
Austrian Fields of Science 2012
106008 Botany, 106042 Systematic botany, 106012 Evolutionary research
Portal url