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We mistook hybridization for evolution?

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At least, translated from Newspeak, that’s what this science PR seems to be saying:

From ScienceDaily:

Advances in genetic studies of birds are changing ornithology research

Because high-throughput sequencing data looks at many genes instead of just a few, it makes it easier to identify very subtle genetic differences between populations, such as the genetics underlying small differences in plumage patterns between different subspecies of Wilson’s Warbler. It can also provide a fresh look at the genetic changes that occur in “hybrid zones,” where the ranges of closely related species overlap and members of the species breed freely with each other, such as where Black-capped and Carolina Chickadees meet in Pennsylvania. The process of one species splitting into two, such as what may be happening with the coastal and inland subspecies of Swainson’s Thrush, is another intriguing area for study. More.

Well, if so, that’s one of the surprises of genome mapping. As with so many things, we start digging into a file, and half the things everyone knows ain’t so. Keeps life interesting.

Here’s the abstract:

The widespread application of high-throughput sequencing in studying evolutionary processes and patterns of diversification has led to many important discoveries. However, the barriers to utilizing these technologies and interpreting the resulting data can be daunting for first-time users. We provide an overview and a brief primer of relevant methods (e.g., whole-genome sequencing, reduced-representation sequencing, sequence-capture methods, and RNA sequencing), as well as important steps in the analysis pipelines (e.g., loci clustering, variant calling, whole-genome and transcriptome assembly). We also review a number of applications in which researchers have used these technologies to address questions related to avian systems. We highlight how genomic tools are advancing research by discussing their contributions to 3 important facets of avian evolutionary history. We focus on (1) general inferences about biogeography and biogeographic history, (2) patterns of gene flow and isolation upon secondary contact and hybridization, and (3) quantifying levels of genomic divergence between closely related taxa. We find that in many cases, high-throughput sequencing data confirms previous work from traditional molecular markers, although there are examples in which genome-wide genetic markers provide a different biological interpretation. We also discuss how these new data allow researchers to address entirely novel questions, and conclude by outlining a number of intellectual and methodological challenges as the genomics era moves forward. Open access – David P. L. Toews, Leonardo Campagna, Scott A. Taylor, Christopher N. Balakrishnan, Daniel T. Baldassarre, Petra E. Deane-Coe, Michael G. Harvey, Daniel M. Hooper, Darren E. Irwin, Caroline D. Judy, Nicholas A. Mason, John E. McCormack, Kevin G. McCracken, Carl H. Oliveros, Rebecca J. Safran, Elizabeth S. C. Scordato, Katherine Faust Stryjewski, Anna Tigano, J. Albert C. Uy, Benjamin M. Winger. Genomic approaches to understanding population divergence and speciation in birds. The Auk, 2015; 133 (1): 13 DOI: 10.1642/AUK-15-51.1

See also: The role that hybridization and other types of change play in evolution

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3 Replies to “We mistook hybridization for evolution?

  1. 1
    goodusername says:

    We mistook hybridization for evolution?

    I believe such a thing could indeed occur, although I have no idea where you think it happened here.

  2. 2
    aarceng says:

    Or does it mean they were varieties of the same species rather than closely related species?

    Since species appears to be poorly defined perhaps we should start using “Kind”.

  3. 3
    Robert Byers says:

    goodusername
    The point is that EVOLUTION did not create the different bird types but instead gen studies are showing its ONLY hybrids.
    Thats the point.
    Why shouldn’t all “speciation ‘ just be the mechanism of hybridism? the important biological changes also could be piggybacking this by other mechanisms.
    No weird mutations need appear. jUst using what you already got.
    Just like people did when colour quickly after the flood.

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