Interactions between flowering plants and their pollinators are known to be responsible for part of the tremendous diversity of the angiosperms, currently thought to number at least 350,000 species. Using a new database of pollinators of the large, globally distributed family Apocynaceae (>5300 species) Ollerton et al. explore how different types of pollination system (bird, bee, moth, fly, etc.) are distributed across the evolutionary tree of the family; how those pollination systems have evolved over time; and how they vary biogeographically. Earlier diverging clades are characterized by a narrower range of pollination systems.
Within Apocynaceae, interactions with pollinators are highly structured both phylogenetically and biogeographically. Variation in transition rates between pollination systems suggest constraints on their evolution, whereas regional differences point to environmental effects such as filtering of certain pollinators from habitats. This is the most extensive analysis of its type so far attempted and gives important insights into the diversity and evolution of pollination systems in large clades.
See also: Jeff Ollerton’s Biodiversity Blog