Biogeography Multiple markers from the chloroplast genome, which is notably variable within Trillium, were sampled and concatenated and used to infer a phylogenetic tree. Using the BioGeoBears R package, multiple models were tested to determine origins and likely dispersal patterns, particularly within Trillium. The results suggest that there have been multiple movements between major geographic areas. In addition, a qualitative comparison was made between these results and current distribution probabilities for selected Sessilium species using a MaxEnt species distribution modeling (SDM) analysis. This analysis has produced hypotheses about possible origins for Sessilium species which will be presented. 1
University of Tennessee, Ecology and Evolutionary Biology, 569 Dabney Hall, Knoxville, TN, 37996-1610, United States2University Of Tennessee, Department Of Ecology & Evolutionary Biology, 569 Dabney Hall, KNOXVILLE, TN, 37996-1610, USA
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ORTIZ-HERRERA, MARIA ANGE-
High population genetic substructure in Hypochaeris leontodontoides (Asteraceae), an endemic rupicolous species of the Atlas Mountains in NW Africa
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ypochaeris leontodontoides is a rupicolous species endemic to the Atlas Mountains (Morocco), where it occurs in scattered populations. This study is an attempt to understand the biogeographic patterns of a high mountain species in a rather little studied region of NW Africa. We used Amplified Fragment Length Polymorphism (AFLP) to investigate the population structure and phylogeography of H. leontodontoides in 19 populations sampled from the entire species distribution range. Multivariate analyses including PCoA, UPGMA analysis, and Bayesian clustering were applied to infer the influence of past biogeographic events. The level of AFLP differentiation among the populations was high (FST=0.508). A significant geographical pattern by mountain region was found, such that the different phylogeographical analyses revealed four main groups corresponding to four well-defined geographic regions: Middle Atlas, Eastern High Atlas, Central High Atlas, and Western High Atlas, and highlighted the Western High Atlas as the most divergent group. Our data also indicate two regions as refuges during the Pleistocene ice ages: the Middle Atlas and the northernmost area of the Western High Atlas.
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University of Sevilla, Biología Vegetal y Ecología, Avenida Reina Mercedes nº6, Sevilla, Sevilla, 41010, Spain2Facultad De Biología, Apartado De Correos 1095, Sevilla, N/A, 41080, Spain3University of Sevilla, Biología Vegetal y Ecología, Avenida Reina Mercedes s/n, Sevilla, Sevilla, 41010, España
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LEE, MICHELLE* 1, CAIRNS, DAVID 2 and GADDIS, KEITH DONALD 2
Treeline advance of white spruce (Picea glauca) in south-central Alaska
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any recent studies have predicted and shown alpine treeline advance throughout the world as a result of global climatic changes. These advances have major implications for the assembly and survival of species that may become marginalized as their habitat is destroyed by this advance. We set out to examine treeline advance patterns in the dominant North American treeline forming species white spruce (Picea glauca) throughout south-central Alaska. We collected and examined dendrochronological data from 17 sites across the state. We used linear regression to examine the age of trees relative to the distance from treeline and found variable treeline patterns. Some sites showed definite treeline advance and others have maintained a stable treeline position. Variation in treeline advance is strongly influenced by underlying topography. Understanding how these ecosystems have responded to recent years of climatic change will help us better predict landscape dynamism in the future.
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University of California, Los Angeles, Department of Ecology and Evolutionary Biology, 612 Charles E. Young Drive South, Box 957246, Los Angeles, CA, 90095, United States2Texas A&M University, Department of Geography, 3147 tamu, College Station, TX, 77843, United States
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BELASKI, WHITNEY* 1, DILLER, SARA and SWANSON, BRAD 1 2
Influence of anthropogenic planting on the phylogeography of wild rice (Zizania spp.) in Michigan
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educed gene flow often results from human actions and this increasing isolation of populations may pose a threat to a variety of plant species. However, excessive gene flow as a result of human actions may also modify genetic structure in plant species and could disrupt local adaptation or other genetic processes, posing another less well-recognized threat to plant species. One species that has been subject to human-mitigated dispersal is Northern wild rice, Zizania palustris, an emergent annual grass found in aquatic systems the Eastern United States. Within the state of Michigan, Z. palustris seeds have been sown by Native American tribes and state agencies to create or supplement populations. Zizania palustris likely has limited natural dispersal ability and so populations in the Lower Peninsula of Michigan may have been isolated from the populations in Minnesota and Wisconsin, known sources for planted seed, for an extended period of time. The goal of our project is to identify whether unique genetic groups are present in Michigan that are distinct from planted strains. To address this question we first investigate whether multiple distinct genetic lineages are present in Michigan using amplified fragment length polymorphism (AFLP) and chloroplast DNA (cpDNA) analysis. Single leaves from individuals were collected in 9 populations of Z. palus-
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