Abstract Detail


Donoghue, Michael [1], Alavez, Veronica [2], Gardner, Jordan [3], Landis, Michael  [3], Moeglein, Morgan [4], Park, Brian [3], Segovia, Ali Citlali [5], Diana, Soriano  [5], Torola, Pamela [3], Cacho, N. Ivalu [6], Olson, Mark [7], Eaton, Deren [8], Edwards, Erika [9].

Integrative studies of replicated evolution in a clade of neotropical Viburnum (Adoxaceae) .

The rapid radiation of the Oreinotinus clade of Viburnum in the Neotropics has been promoted by the repeated evolution of a particular set of leaf forms in isolated mountain regions from eastern Mexico to northern Argentina. Our RAD-seq and morphometric analyses have confirmed that large-pubescent-toothed (LPT) leaves and small-glabrous-entire (SGE) leaves have evolved multiple times in parallel, most likely from an intermediate ancestral form that spread southward through the cloud forests. This may have been facilitated by stereotyped patterns of leaf variation within individual plants (juvenile to adult phase changes and seasonal heteroblasty) that may have enabled heterochronic shifts, as well as by shifts in flowering times. Our climate and niche analyses indicate subtle but significant differentiation of species within each region with respect to precipitation and temperature variables, but with LPT species behaving differently in different regions. This is consistent with our physiological data showing that LPT species exhibit a wider range with respect to drought tolerance than do SGE species. Variation in vessel diameter is almost entirely driven by plant height, though species with larger leaves have slightly wider vessels than those with smaller ones, and climate has no effect on vessel diameter.  We have also begun to characterize the insects that cause extensive damage to the leaves of LPT and SGE species, and we are exploiting a large and long-standing hybrid zone and admixture mapping to identify the genes underlying the variable leaf traits. Taken together, our studies paint a complex picture of repeated ecological speciation, with altitudinal differentiation of phenotypes and phenologies in disjunct mountain ranges.  

1 - Yale University, Department Of Ecology And Evolutionary Biology, Po Box 208106, New Haven, CT, 06511, United States
2 - Insituto de Biologia, UNAM, Botany, Mexico City
3 - Yale University , Ecology and Evolutionary Biology , 21 Sachem Street , New Haven , CT, 06511, USA
4 - Yale University
5 - UNAM, Instituto de Biología , 3er circ de CU, Mexico City , DF, 04510, Mexico
6 - Insituto De Biología, UNAM, Botánica, 3er Circuito De Ciudad Universitaria S/n, Del. Coyoacan, CDMX, DIF, 04510, Mexico
7 - Insituto de Biologia, UNAM
8 - Columbia University, Ecology, Evolution, And Environmental Biology, 1200 Amsterdam Ave. , Schermerhorn Ext. Office 1007, New York, NY, 10027, United States
9 - Yale University, Department Of Ecology And Evolutionary Biology, 165 Prospect St, New Haven, CT, 06511, United States


Presentation Type: Oral Paper
Abstract ID:1071
Candidate for Awards:None

Copyright © 2000-2019, Botanical Society of America. All rights reserved