Local adaptation at the range peripheries of Sitka spruce. J Evol Biol

Forest Sciences and Centre for Forest Conservation Genetics, University of British Columbia, Vancouver, BC, Canada.
Journal of Evolutionary Biology (Impact Factor: 3.23). 12/2009; 23(2):249-58. DOI: 10.1111/j.1420-9101.2009.01910.x
Source: PubMed


High-dispersal rates in heterogeneous environments and historical rapid range expansion can hamper local adaptation; however, we often see clinal variation in high-dispersal tree species. To understand the mechanisms of the species' distribution, we investigated local adaptation and adaptive plasticity in a range-wide context in Sitka spruce, a wind-pollinated tree species that has recently expanded its range after glaciations. Phenotypic traits were observed using growth chamber experiments that mimicked temperature and photoperiodic regimes from the limits of the species realized niche. Bud phenology exhibited parallel reaction norms among populations; however, putatively adaptive plasticity and strong divergent selection were seen in bud burst and bud set timing respectively. Natural selection appears to have favoured genotypes that maximize growth rate during available frost-free periods in each environment. We conclude that Sitka spruce has developed local adaptation and adaptive plasticity throughout its range in response to current climatic conditions despite generally high pollen flow and recent range expansion.

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Available from: Sally N Aitken, Sep 17, 2014
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    • "A major challenge in predicting the impacts of climate change on biodiversity is to move beyond species-level models and towards a greater consideration of intraspecific variation in climatic tolerances due to local adaptation (Jump & Penuelas 2005; Jay et al. 2012). While most models assume uniformity of climate responses below the species level, in reality local adaptation of different populations is common among many plants and animals (Kawecki & Ebert 2004; Savolainen et al. 2007; Leimu & Fischer 2008), and intraspecific variation in climatic tolerances and local adaptation has been documented for many physiological and life-history traits (Savolainen et al. 2007; Mimura & Aitken 2010; Keller et al. 2011b). In the current era of environmental change, key objectives for the future will thus be translating intraspecific variation in climate responses into landscape models of local adaptation, and identifying geographic regions that are predicted to be most sensitive to disruption of standing patterns of local adaptation under climate change (Jay et al. 2012; Weinig et al. 2014). "
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    Ecology Letters 12/2014; 18(1). DOI:10.1111/ele.12376 · 10.69 Impact Factor
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    • "The use of wild populations not only allows the study of species for which common garden experiments are not feasible, but also the study of the interaction with local conditions. If differences in the reaction norm of local populations were due to environmental imprinting, common garden experiments may mask phenotypic variability that could be potentially important to explain evolutionary processes at the edge of the geographical range of species [44]–[46]. "
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    PLoS ONE 08/2014; 9(8):e104734. DOI:10.1371/journal.pone.0104734 · 3.23 Impact Factor
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