Phylogenetic analysis of fossil flowers using an angiosperm-wide data set: proof-of-concept and challenges ahead

Author(s)
Jürg Schönenberger, Anna Maria Louise von Balthazar-Schönenberger, Andrea Lopez Martinez, Beatrice Albert, Charlotte Prieu, Susana Magallon, Herve Sauquet
Abstract

Premise: Significant paleobotanical discoveries in recent decades have considerably improved our understanding of the early evolution of angiosperms and their flowers. However, our ability to test the systematic placement of fossil flowers on the basis of phylogenetic analyses has remained limited, mainly due to the lack of an adequate, angiosperm-wide morphological data set for extant taxa. Earlier attempts to place fossil flowers phylogenetically were, therefore, forced to make prior qualitative assessments of the potential systematic position of fossils and to restrict phylogenetic analyses to selected angiosperm subgroups. Methods: We conduct angiosperm-wide molecular backbone analyses of 10 fossil flower taxa selected from the Cretaceous record. Our analyses make use of a floral trait data set built within the framework of the eFLOWER initiative. We provide an updated version of this data set containing data for 28 floral and two pollen traits for 792 extant species representing 372 angiosperm families. Results: We find that some fossils are placed congruently with earlier hypotheses while others are found in positions that had not been suggested previously. A few take up equivocal positions, including the stem branches of large clades. Conclusions: Our study provides an objective approach to test for the phylogenetic position of fossil flowers across angiosperms. Such analyses may provide a complementary tool for paleobotanical studies, allowing for a more comprehensive understanding of fossil phylogenetic relationships in angiosperms. Ongoing work focused on extending the sampling of extant taxa and the number of floral traits will further improve the applicability and accuracy of our approach.

Organisation(s)
Department of Botany and Biodiversity Research
External organisation(s)
Universidad Nacional Autonoma de Mexico, Université Paris XI - Paris-Sud, Royal Bot Gardens & Domain Trust, Natl Herbarium New South Wales NSW, University of New South Wales
Journal
American Journal of Botany: the journal for all plant biologists
Volume
107
Pages
1433-1448
No. of pages
16
ISSN
0002-9122
DOI
https://doi.org/10.1002/ajb2.1538
Publication date
10-2020
Peer reviewed
Yes
Austrian Fields of Science 2012
106008 Botany, 106042 Systematic botany, 106012 Evolutionary research
Keywords
Portal url
https://ucris.univie.ac.at/portal/en/publications/phylogenetic-analysis-of-fossil-flowers-using-an-angiospermwide-data-set-proofofconcept-and-challenges-ahead(1e88c79d-6ea9-4f9e-ab5a-c90817e232b6).html