Stevens, Sally , Emery, Nancy .
Stuck between a rock and a hot place: the role of climate in driving population and species boundaries in an endemic Appalachian fern species.
Global climate change has motivated research that seeks to quantify the climatic tolerances of plant species in an effort to understand and predict the response of vegetation to shifting temperature and precipitation regimes. Several recent studies have focused on understanding the role of climate in setting species geographic range limits and the prevalence of local adaptation among populations to their respective climatic conditions within that geographic range. However, much less is known about how distribution shifts at micro-climatic, local scales may change with warming temperatures and influence range-wide responses; which may be particularly important for those species that are potentially dispersal limited, such as the fern species, Vittaria appalachiana. This tropical relict species is asexual, dominated by the gametophytic generation, and restricted to recessed back-walls of non-calcareous rock shelters and crevices that are found in an island-like distribution throughout the Appalachian Mountain Range. Thus, this fragmented habitat and the biology of the species may inhibit range shifting and adaptation in the face of a changing climate. Our goal is to test the hypothesis that rock shelters buffer V. appalachiana populations from fluctuating seasonal temperatures, which enables this species to persist in temperate North America. We also hypothesize that the patchy distribution of shelters throughout the geographic range and the lack of sexual reproduction has facilitated local adaption of populations to the average annual temperatures experienced in their respective regions. Thus, we predict a narrow temperature tolerance range for the species as a whole, but variation among populations due to local adaptation. Here, we present preliminary data that quantifies temperature variation at both local and range-wide spatial scales and describe ongoing field and growth chamber experiments designed to test our hypotheses. Together, these results will provide important information about the role of climate variation across spatial scales in determining species distributions and the ability of a dispersal-limited gametophyte to respond to future climatic changes.
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1 - Purdue University, Department of Botany and Plant Pathology, 915 West State Street, West Lafayette, IN, 47907-2054, USA
2 - Purdue University, Department Of Biological Sciences, 915 West State Street, West Lafayette, IN, 47907-2054, USA
Presentation Type: Poster:Posters for Sections
Location: Battelle South/Convention Center
Date: Monday, July 9th, 2012
Time: 5:30 PM