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Showing 1 to 13 of 13 for “"clines"”.
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Signatures of natural selection and local adaptation in Populus trichocarpa and Populus deltoides along latitudinal clines
Trees, like many other organisms, decrease their rate of metabolic activities to cope up with harsh environments. This stage of "dormancy" is marked by shedding of leaves and bud-set in deciduous trees. Recent studies have revealed the role of the circadian clock in synchronizing the timing of …
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Adaptation to altitude in Heliconius butterflies
… The environment changes drastically along steep clines, such as mountains, and diverse sets of challenges are predicted to drive local adaptation. Thus, these clines represent ideal settings to identify the traits and genomic mechanisms that allow some organisms to succeed across wide …
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Biogeographical Approaches for Studying Species Invasion
… of P. australis have evolved latitudinal clines on traits associated with herbivory, specifically for aphid Hyalopterus pruni. For a chewing herbivore, Spodoptera frugiperda, only native genotypes exhibited latitudinal clines. The existence of non-parallel latitudinal gradients between …
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Ecological genomics and conservation of caribou in Western North America
… favor different phenotypes along environmental clines. Clines are also compatible with balancing forces, which maintain phenotypic polymorphisms within populations -for example, migratory or sedentary behaviour in caribou. The use of genomics is fundamental to evaluate such evolutionary …
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Partitioning of multivariate phenotypes using regression trees reveals complex patterns of adaptation to climate across the range of black cottonwood (Populus trichocarpa)
… and phenological traits. Latitudinal clines for the relevant component traits are frequently observed for species that have a north-south distribution, but these relationships do not account for climatic variation within a given latitudinal band, which may be reflected in adaptive …
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Population Variation in the Mitochondrial-DNA of Two Marine Organisms: The Hard Shell Clam <i>Mercenaria spp.</i> and the Killifish, <i>Fundulus Heteroclitus</i>
… maintenance of morphological and gene frequency clines in killifish. Effective migration rate was concluded using mtDNA haplotype frequencies for five partially isolated populations. From F<sub>st</sub>, N<sub>e</sub>m was estimated to be 24.09. The corresponding value from a private alleles-type …
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The genetic basis of reproductive isolation in house mice: Studies of a European hybrid zone
… the locations and shapes of allele frequency clines are distorted by selection against hybrids, with effects related to the dominance of the interacting alleles and inheritance patterns of the X chromosome (hemizygosity). Additionally, loci closely linked to the targets of selection show only …
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Nuclear and cytoplasmic genetic variation in Picea: DNA markers for evaluating past migration, introgression and evolutionary history
… two species. An east-west divide and opposing clines of chloroplast haplotypes in black spruce are consistent with leptokurtic dispersal out of either (1) a southeast glacial refugium of North America or (2) a small hypothetical northwestern refugium.</p><p>Some individual markers within …
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An Examination of Athletic Directors' Perceptions of the Utilization of Athletic Trainers in the Secondary School Setting
<p>Many secondary school athletes are lacking appropriate medical care during sport participation. Athletic trainers (ATs) are qualified healthcare professionals that can fill this need. Barriers to hiring ATs within this setting have been identified, however important information from …
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Confessional Politics and Religious Identity in the Early Jesuit Missions to the Ottoman Empire
<p>In its first century, the Society of Jesus undertook numerous missions to the various Christian communities of the Ottoman Empire. In each instance, the Jesuits faced obstacles to their efforts to Catholicize the Christian Orient. Through an examination of the Jesuit experience in the early …
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Reproductive patterns of deep-sea invertebrates related to phylogeny and energy availability
… at higher latitudes and deeper depths. These clines of fecundity and egg size are discussed in relation to environmental factors experienced by the adult females and larvae. In the hydrothermal vent shrimps, the three species produced a high number of small eggs. The fecundity of the …
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Assessing genomic variation in the hopbush, Dodonaea viscosa, to investigate micro-evolution and adaptation
… Selection acting on these populations has led to clines in allele frequencies in a number of functional genes, including some genes associated with leaf shape and stomatal characteristics, the phenotypes for which have been observed previously to vary along this environmental gradient. The …
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Role of Genotype-by-Temperature Interactions in the Maintenance of Polygenic Sex Determination in the House Fly
Sex determination is the process by which sexually dimorphic developmental pathways are established. In genetic sex determination systems, a single master regulatory locus determines the sex of an individual. However, some organisms have multiple master sex determining loci in their genome that …