Abstract Detail

Ecophysiology

Jones, Cynthia [1], Martinez-Cabrera, Hugo [2], Nicotra, Adrienne [3], Mocko, Kerri [4], Marais, Elizabeth [5], Schlichting, Carl [6].

Phylogenetic influences on leaf trait integration in Pelargonium: convergence, divergence and historical adaptation to a rapidly changing climate.

Past and future responses of plant lineages to rapid climate change are likely to be strongly influenced by functional traits, but whether these influences are exerted through mean trait values versus interactions among traits remains largely unexplored. The morphologically diverse species of the South African genus Pelargonium are contained in major clades that have radiated along the same seasonal aridity gradient, thereby presenting the opportunity to ask whether leaf trait integration parallels evolutionary convergence or divergence of mean trait values in each clade. Seven leaf traits were measured on field-collected leaves from one-third of the South African species. Mean trait values were compared across major clades using analysis of variance; trait integration was examined using phylogenetic regression among traits within major clades. Mean trait values between sister Clades A1 and A2 diverged significantly and were consistent with expectations for leaves differing in longevity, but patterns of trait integration were convergent. In contrast, species in Clades C and A2 included in this study converged in mean values of individual traits, except for δ¹³C, but exhibited divergent patterns of trait integration. Divergent present-day patterns of trait integration are consistent with interpretations of adaptive responses to the prevailing climate at the time of each clade's origin. These differing patterns of integration are likely to exert strong effects on clade-level responses to future climate change in the winter rainfall region of South Africa.

Broader Impacts:

1 - University of Connecticut, Department of Ecology & Evolutionary Biology, 75 N. Eagleville Road, Unit 3043, Storrs, CT, 06269-3043, USA
2 - Université du Québec à Montréal, Département des science biologiques, CP 8888, Succ., Centre Ville Montréal, QC, H3C 3P8, Canada
3 - AUSTRALIAN NATIONAL UNIVERSITY, DIV OF BOTANY & ZOOLOGY, Division Of Evolution, Ecology And Genetics, Daley Rd., CANBERRA, N/A, 0200, Australia
4 - University of Connecticut, Ecology And Evolutionary Biology, U-3043, 75 N. Eagleville Rd, Storrs, CT, 06269, USA
5 - University of Stellenbosch, Department Forest and Wood Science, Private bag X1, Stellenbosch, Matieland, 7602, South Africa
6 - University of Connecticut, Department of Ecology & Evolutionary Biology, 75 N. Eagleville Road, Unit 43, Storrs, CT, 06269-3043, USA

Keywords:
Pelargonium
functional leaf traits
trait integration.

Presentation Type: Oral Paper:Papers for Topics
Session: 27
Location: Elmwood/Riverside Hilton
Date: Tuesday, July 30th, 2013
Time: 10:30 AM
Number: 27002
Abstract ID:299
Candidate for Awards:None