Genetic Barcode RFLP Analysis of the Nelson's and Saltmarsh Sparrow Hybrid Zone

@inproceedings{Walsh2011GeneticBR,
  title={Genetic Barcode RFLP Analysis of the Nelson's and Saltmarsh Sparrow Hybrid Zone},
  author={Jennifer Walsh and Adrienne I. Kovach and Oksana P. Lane and Kathleen M. O’Brien and Kimberly J. Babbitt},
  year={2011}
}
Abstract Hybridization between Saltmarsh Sparrow (Ammodramus caudacutus) and Nelson's Sparrow (A. nelsoni) has been documented in areas where the two species occur sympatrically, increasing the difficulty of accurate species identification. We developed a DNA barcoding restriction fragment length polymorphism (RFLP) test to discriminate between Nelson's Sparrows and Saltmarsh Sparrows and applied it to 426 putative Saltmarsh Sparrows sampled from Maine to New York, USA. All individuals were… 
Relationship of phenotypic variation and genetic admixture in the Saltmarsh–Nelson's sparrow hybrid zone
TLDR
It is concluded that the discrimination of pure and hybrid individuals is not possible in the absence of genetic data, which has implications for conservation of pure populations, as extensive backcrossing throughout the hybrid zone may present challenges for monitoring pure species identified by morphology alone.
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TLDR
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TLDR
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TLDR
Differences in reproductive success among pure and admixed individuals coupled with intrinsic mechanisms (reduced survival in F1 females) shape hybrid zone dynamics in this system, and saltmarsh sparrows are predicted to be better adapted to nesting in salt marshes.
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