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Female dispersal and gene flow Low High Male dispersal and gene flow Low High Geographic structure in… mtDNA-- yes Autosomal genes-- yes Y-linked genes-- yes Demographic autonomy-- yes Geographic structure in… mtDNA-- yes Autosomal genes-- no Y-linked genes-- no Demographic autonomy-- yes Geographic structure in… mtDNA-- no Autosomal genes-- no Y-linked genes-- *** Demographic autonomy-- *** Geographic structure in… mtDNA-- no Autosomal genes-- no Y-linked genes-- no Demographic autonomy-- no Relationship between population genetic structure and gender specific dispersal and gene flow
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Using “acquired” markers to complement molecular studies Measuring isotope ratios in tissues Measuring parsite loads Physical tags (e.g. bird bands) Radio transmitters Can tell you about the movements and spatial preferences of animals. Are not transmitted across generations so do not provide historical data. Some Examples:
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Breeding areaNon-breeding area Freshwater Fishes Genetic markers Acquired markers Population structure registered by High Vagile Fishes ocean Anadromous Fishes Low stream ocean HighLow * Catadromous Fishes stream ocean LowHigh * acquired individuals sampled here
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Mixed-Stock Assessments of Fish Introductions Some examples and outcomes: Hybridization was observed among landlocked brown trout and introduced anadromous forms in the Conwy River of N. Wales, but introduced forms in Spain went extinct. diagnostic salmon markers for anadromous forms? See Figure 9.4 streams
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Mixed Stock Analysis in Conservation Biology Loggerhead Turtle Caretta caretta 20,000 caught in swordfish longlines in Mediterranean each year (~20% die). Only 50% of the catch originate from Mediterranean Beaches. Determined using maximum likelihood analysis of mtDNA
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Evolutionary verses Management Units At a shallow-level: MU: Any population that exchanges so few migrants with others as to be genetically distinct from them will normally also be demographically independent. e.g. rookeries of sea turtles in the same ocean basin At a deeper level: EU: One or a set of populations with a distinct long-term evolutionary history mostly separate from that of other such units. e.g. Pacific rookeries vs Atlantic rookeries (figure 6.5)
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Molecular Analyses Have Revealed EUs When They Weren’t Expected African elephants (Loxodonta) As a result of molecular analyses two species are now recognized: L. Africana and L. cyclotis See Figure 9.6 and Table 9.3
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Molecular Analyses Have Failed to Reveal EUs When They Were Expected Dusky Seaside sparrow Avise and Nelson, 1989 Driven to extinction, many thought it was a distinct evolutionary lineage. But see Figure 9.7
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Guidelines for Conserving Phylogeographic Diversity Limit unnecessary transplantations. There are concerns even when transplanting pops within species. The burden of proof should be on the advocates of the transplantation. Design regional reserves. Identify areas that contain sources of phylogeographic diversity…..”phylogeographic parks” Focus on preserving biodiversity rather than preserving special features of the landscape. Cyprinodon desert pupfish
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Recognition of Endangered Species Continued support for the Endangered Species Act and CITES Under ESA: listings maybe made for a species, a subspecies, or a distinct population segment (shares common lineage). “Endangered” = At risk of extinction throughout all or a significant portion of its range “Threatened” = Likely to become endangered in the foreseeable future.
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Molecular Forensics Numerous examples where molecular markers have been used to identify the species or geographical source of a commercial animal product. Table 9.5 Figure 9.9 Show Tsukiji Fish Market Slides
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Ranking Taxa For Conservation In Management Practice: Rarity Restricted distribution Ecological importance Charisma Economics Management feasibility Phylogenetic distinctiveness Figure 9.13
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