Abstract Detail


Karimi, Nisa [1], Lemmon, Alan [2], Lemmon, Emily [2], Hernandez, Adriana [3], Eifler, Evan [4], Strickler, Susan [5], Specht, Chelsea [6], Givnish, Thomas [7].

Phylogenomics, reticulate evolution, historical biogeography, shifts in climatic niche, and parallel adaptive radiations in floral syndrome in the genus Calochortus (Liliaceae).

Calochortus consists of ca. 75 species of bulbous herbs displaying striking floral diversity and often narrow geographic distributions. Calochortus occurs across western North America from British Columbia to the Dakotas, and south to Mexico and Guatemala, with a center of diversity in California. Many species are restricted to serpentine soils or other unusual substrates. The group exhibits striking variations in floral color and morphology, with four principal floral syndromes (mariposas, cat’s ears, star tulips and fairy lanterns). Previous research based on three plastid loci showed that Calochortus is comprised of seven major clades generally aligned with geography, not floral morphology, indicating recurrent evolution of floral syndromes across multiple lineages and apparently limited geographic dispersal through time. Early data indicated substantial conflict between limited plastid data and nrDNA ITS sequences, suggesting reticulate evolution and the possibility of widespread hybridization. Here we use targeted-sequence capture of hundreds of low-copy nuclear loci and whole plastomes to infer the phylogeny of Calochortus, to reconstruct floral evolution and historical biogeography. Based on conflict between the nuclear and plastome trees, and concordance analysis of the nuclear data, reticulate evolution – most likely reflecting hybridization and introgression – appears to be frequent and widespread within the genus. We use the time-calibrated nuclear phylogeny to explore historical biogeography and the evolution of floral syndromes and climatic niches in Calochortus. We explored whether parallel evolution of such syndromes and niches have occurred in different major clades, and tested whether the recurrent evolution of individual floral syndromes is associated with particular climatic niches or habitats, as hypothesized based on the impact of syndromes on floral temperature and evaporation rates under different conditions. We used recently developed techniques in phylogenetic network inference to test these questions, taking reticulation into account.

1 - University of Wisconsin - Madison, Department Of Botany, 430 Lincoln Drive, Madison, WI, 53706, United States
2 - Florida State University, 400 Dirac Science Library, Tallahassee, FL, 32306
3 - Cornell University, Plant Biology and the L.H. Bailey Hortorium, School of Integrative Plant Science, 506 Mann Library Building, Ithaca, NY, 14850, USA
4 - UW Madison, Botany, 430 Lincoln Dr., Madison, WI, 53706, United States
5 - Boyce Thompson Institute For Plant Research , 533 Tower Road, Ithaca, NY, 14853, United States
6 - Cornell University, School of Integrative Plant Science and L.H. Bailey Hortorium, 502 Mann Library, Ithaca, NY, 14850, USA
7 - University Of Wisconsin-Madison, Department Of Botany, Birge Hall, 430 Lincoln Drive, Madison, WI, 53706, United States

none specified

Presentation Type: Oral Paper
Session: PHYL4, Phylogenomics IV
Location: Virtual/Virtual
Date: Friday, July 31st, 2020
Time: 3:30 PM
Number: PHYL4003
Abstract ID:807
Candidate for Awards:None

Copyright © 2000-2020, Botanical Society of America. All rights reserved