Abstract Detail


Chomentowska, Anri [1], Guilliams, C. Matt [2], Ogburn, Matthew [3], Hancock, Lillian [4], Holtum, Joseph [5], Edwards, Erika [1].

ddRADSeq phylogeny and systematics of the Cistantheae clade (Montiaceae).

The plants in the family Montiaceae (Caryophyllales) have an affinity for dry and alpine habitats and exhibit a highly labile life history and climate niche. Lability in life history traits has been shown to cluster especially in one North and South American subclade, Cistantheae. However, the study into the evolution of this group has been stymied thus far by unresolved phylogenies, exacerbated by decades of taxonomic confusion due to the presence of intraspecific variation in morphology. In this study, we clarify phylogenetic relationships among multiple Cistantheae subsections and delimitate species using a reduced-representation genome sequencing technique, specifically ddRAD-seq. We sequenced 179 plant specimens collected largely from Chile and California; the sequencing reads were assembled de novo and with a whole-transcriptome reference. At the family Montiaceae-scale, our phylogenetic analyses, based both on maximum likelihood methods and quartet-based species tree inference, resulted in dubious topologies, perhaps owning to the high degree of missing data. When we subset the data into Cistantheae and its subsections, however, we obtained much better resolution and support for our phylogenies. We also applied phylogenomic and population genomic methods to look for signatures of gene flow and incomplete lineage sorting. These analyses supported several phylogenetic hypotheses from previous studies and revealed possible instances where species have been over-split that need taxonomic revision. While ddRAD-seq methods are very useful in parsing out within-genus ambiguities and delimitating species, its limitations are felt at larger-scale phylogenetic applications.

1 - Yale University, Department Of Ecology And Evolutionary Biology, 165 Prospect St, New Haven, CT, 06511, United States
2 - Santa Barbara Botanic Garden, 1212 Mission Canyon Road, Santa Barbara, CA, 93105, United States
3 - Southern Utah University, Department of Biology, 351 W University Blvd., Ceder City, UT, USA
4 - Brown University, Department of Ecology and Evolutionary Biology, Box G-W, Providence, RI, 02912, USA
5 - James Cook University, College of Science and Engineering, Townsville, Queensland, 4811, Australia


Presentation Type: Oral Paper
Number: COOLEY005
Abstract ID:898
Candidate for Awards:George R. Cooley Award

Copyright © 2000-2022, Botanical Society of America. All rights reserved