Abstract Detail

Systematics Section/ASPT

Clement, Wendy [1], Cohen, Alanna [2], Donoghue, Michael [3].

A comparison of nuclear and chloroplast gene trees for Viburnum (Adoxaceae).

Recent efforts focused on reconstructing the evolutionary history of Viburnum have resulted in a near-complete species level phylogeny. This tree resolves many of the major clades of Viburnum and provides strong support for deep relationships among the clades. Further, this phylogeny has served as a foundation for taxonomic revision, evolutionary studies of leaf morphology and anatomy, diversification rate analysis, and reconstruction of ancestral environments. Sampling 152 of the ~165 species recognized, the most current phylogeny is primarily based on plastid gene regions as well as the internal transcribed spacer region (ITS). Few significant conflicts between ITS and plastid gene trees have been identified and may point to possible hybridization events. Although this work has provided us with a robust framework to explore the evolutionary history of Viburnum, these data do not account for the nuclear genome. In 2004, a 41-taxon phylogeny was reconstructed based on the low copy nuclear granule bound starch synthase gene region (GBSSI or waxy). The sampling in this work no longer reflects the phylogenetic diversity within Viburnum. Here we expand the sampling of waxy to include an additional 65 Viburnum species that now represent all currently recognized clades of Viburnum, and we compare it to our current understanding of Viburnum phylogeny based on plastid and ITS data. Evolutionary relationships based on GBSSI data for 106 species recovered all currently recognized major clades of Viburnum and echo previously identified conflicts. However, these data also reflect several new relationships that conflict with plastid or ITS data. Here we highlight these conflicts, explore additional evidence based on morphology and biogeography, and discuss the potential causes for differing gene histories. Lastly we evaluate the impact of these conflicts on current hypotheses of morphological evolution and biogeography and discuss how these newly proposed relationships affect our ongoing studies of Viburnum evolution.

1 - The College Of New Jersey, Biology, 2000 Pennington Road, Department Of Biology, Ewing, NJ, 08638, USA
2 - The College of New Jersey, Biology, 2000 Pennington Road, Ewing, New Jersey, 08628, United States
3 - Yale University, Department Of Ecology And Evolutionary Biology, 21 Sachem Street, PO Box 208105, New Haven, CT, 06511, USA

Keywords:
Viburnum
gene trees.

Presentation Type: Oral Paper:Papers for Sections
Session: 60
Location: Salon 2/The Shaw Conference Centre
Date: Wednesday, July 29th, 2015
Time: 11:15 AM
Number: 60013
Abstract ID:904
Candidate for Awards:None