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Locally adapted fish populations maintain small-scale genetic differentiation despite perturbation by a catastrophic flood eventPlath, Martin, Hermann, Bernd, Schröder, Christine, Riesch, Rüdiger, Tobler, Michael, García de León, Francisco J., Schlupp, Ingo, Tiedemann, Ralph January 2010 (has links)
Background: Local adaptation to divergent environmental conditions can promote population genetic differentiation even in the absence of geographic barriers and hence, lead to speciation. Perturbations by catastrophic events, however, can distort such parapatric ecological speciation processes. Here, we asked whether an exceptionally strong flood led to homogenization of gene pools among locally adapted populations of the Atlantic molly (Poecilia mexicana, Poeciliidae) in the Cueva del Azufre system in southern Mexico, where two strong environmental selection factors (darkness within caves and/or presence of toxic H2S in sulfidic springs) drive the diversification of P. mexicana. Nine nuclear microsatellites as well as heritable female life history traits (both as a proxy for quantitative genetics and for trait divergence) were used as markers to compare genetic differentiation, genetic diversity, and especially population mixing (immigration and emigration) before and after the flood.
Results: Habitat type (i.e., non-sulfidic surface, sulfidic surface, or sulfidic cave), but not geographic distance was the major predictor of genetic differentiation. Before and after the flood, each habitat type harbored a genetically distinct population. Only a weak signal of individual dislocation among ecologically divergent habitat types was uncovered (with the exception of slightly increased dislocation from the Cueva del Azufre into the sulfidic creek, El Azufre). By contrast, several lines of evidence are indicative of increased flood-induced dislocation within the same habitat type, e.g., between different cave chambers of the Cueva del Azufre.
Conclusions: The virtual absence of individual dislocation among ecologically different habitat types indicates strong natural selection against migrants. Thus, our current study exemplifies that ecological speciation in this and other systems, in which extreme environmental factors drive speciation, may be little affected by temporary perturbations, as adaptations to physico-chemical stressors may directly affect the survival probability in divergent habitat types.
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Nervous control of liver metabolism and hemodynamicsGardemann, Andreas, Püschel, Gerhard, Jungermann, Kurt January 1992 (has links)
Content:
Anatomy of hepatic innervation
In vivo studies on the role of hepatic nerves
Effects of hepatic nerves in isolated perfused liver
Mechanism of action of sympathetic hepatic nerves
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Characterization of DNA binding properties of two nuclear proteins from brainRaghunathan, A 07 1900 (has links)
DNA binding properties
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Metabolism of arachidonic acid via the lipoxygenase pathway in sheep uterusSurapureddi, Sailesh 11 1900 (has links)
Lipoxygenase pathway in sheep uterus
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Development of aneuploids of Pennisetum glauhum (L)R.Br as a base for high density chromosome mappingChirumamille, Nagesh 12 1900 (has links)
Pennisetum glauhum (L)R.Br as a base for high density chromosome mapping
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Isolation and characterization of nuclear matrix proteins from brain cell types: Possible utility in cancer cell linesRaju, Nivarthi Naga 08 1900 (has links)
Isolation and characterization of nuclear matrix proteins
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97 |
Studies on neurotransmitter function of acetylcholine in experimental hyperammonemiaDevi, Rukmini R P 05 1900 (has links)
Studies on neurotransmitter function
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98 |
Studies on diazotrophy and its regulation by salinity stress and osmotic stress in the cyanobacterium nostoc muscorumDevulapalli, Chakravarthy January 1996 (has links)
Studies on diazotrophy and its regulation
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Studies on the interaction between glutathione and hypothalamic peptide hormones in the rat brainPasha, Vali K 05 1900 (has links)
Interaction between glutathione and hypothalamic peptide hormones in the rat brain
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100 |
Regulation of aerobic hydrogen metabolism in diazotrophic cyanobacteriaKumar, Pratap A 09 1900 (has links)
Regulation of aerobic hydrogen metabolism
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