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Abstract Calceolaria (Calceolariaceae) is an emblematic and diverse genus in the Americas. Despite being one of the most easily recognized genera in the region and a system with great potential to improve our understanding of different drivers of species diversification in the Andes, its intrageneric evolutionary relationships are still poorly understood. Responding to the need for additional molecular markers to resolve the phylogenetic relationships of the group, we perform plastome analyses and resolve the backbone of the genus. Specifically, using low-coverage genomes for 14 species, we assembled plastomes, estimated and dated phylogenetic hypotheses and evaluated evolutionary trends in the group. Our approach allowed us to resolve the backbone of the genus, identify two main clades and estimate a timing of diversification contemporaneous to major climatic and orogenic events. Our biogeographic reconstructions suggest an independent colonization of the whole range of the genus by both clades. Finally, our evaluations of floral morphology reveal future avenues for investigating the relationship between the pollination biology and diversification of the group.
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Widespread evolution of poricidal flowers: A striking example of morphological convergence across flowering plants
Summary The evolution of tube-like floral morphologies that control pollen release via small openings (functionally poricidal flowers) represents a taxonomically and geographically widespread instance of repeated and independent evolution of a functionally similar morphology. Poricidal flowers are often closely associated with buzz pollination by bees, but we lack an updated angiosperm-wide survey of their phylogenetic distribution.We identify all presently known angiosperm genera containing poricidal flowers via a literature survey. We determined the phylogenetic distribution of poricidal flowers and minimum number of independent gains and losses via a genus-level and species level angiosperm-wide phylogeny. We estimated if evolution of poricidal flowers is associated with changes in speciation/extinction via diversification rate analyses.Poricidal flowers occur across at least 87 angiosperm families and 635 genera containing > 28,000 species. At the genus level, more than 200 independent gains and 145 independent losses of poricidal flowers occurred. Across angiosperms, genus-level analyses suggest poricidal flower evolution is associated with lower net diversification rates (origination-extinction). Species-level analyses argue no diversification linked to poricidal morphology but within the two focal families we found family-specific diversification effects.We present different hypotheses for the functional significance of poricidal flowers, including its association with buzz pollination, and suggest future directions for studies elucidating the extent to which morphological and functional convergence of poricidal flowers are correlated.
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- Award ID(s):
- 2323170
- PAR ID:
- 10536588
- Publisher / Repository:
- bioRxiv
- Date Published:
- Format(s):
- Medium: X
- Institution:
- bioRxiv
- Sponsoring Org:
- National Science Foundation
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Accepted Manuscript1.0
- Posted Content:
- https://doi.org/10.1101/2024.02.28.582636
