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Re: [CALBIRDS] Re: Who's On First?

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  • Don Roberson
    I m wondering if we re straying for Cal Bird topics too much, but Jim Gain asks whether it is likely the AOU will make further changes in the sequence of the
    Message 1 of 9 , Jul 31, 2004
      I'm wondering if we're straying for Cal Bird topics too much, but Jim
      Gain asks whether it is likely the AOU will make further changes in the
      sequence of the checklist. The answer is "yes" -- there are likely to
      be more changes -- but I also do not anticipate them for several years
      because the research is so new (see below). I recommend changing to the
      now-official AOU standard sequence -- as shown on the AOU and CBRC web
      sites, previously referred to in this thread.

      The Sibley-Ahquist-Monroe DNA-DNA hybridization studies were the last
      comprehensive look at sequencing the birds of the world that had a major
      impact (e.g., Sibley & Ahlquist 1990, Sibley & Monroe 1990). DNA-DNA
      hybridization studies inferred relationships by measuring the
      temperature at which artificially-created hybrid DNA double helixes of
      different birds "melted." This indirect method of looking at genetic
      evidence was somewhat replaced in the 1990s by more direct studies of
      mitochondrial DNA, and even more recently be looking at the direct
      genetic sequences in nuclear DNA.

      Recently, studies of nuclear DNA genetic codes have produced trees of
      relationships of all of Sibley-Ahlquist-Monroe's families (except one)
      and these studies will have a major impact on the AOU and others who
      produced checklists. A fair bit of recent work appears in the
      arrangement in the newest Howard & Moore Checklist (2003 -- Clements is
      oh so passe), and the topic of passerine evolution (and thus sequencing)
      is now published in Barker, Garrowclough & Groth (2002) "A phylogenetic
      hypthesis for passerine birds: taxonomic and biogeopgraphic implications
      of an analysis of nuclear DNA sequence data" Proc. R. Soc. Lond. B. 269:
      295-305; Erickson, Irestedt & Johansson (2003) "Evolution, biogeography,
      and patterns of diversidfication in passerine birds" Jour. Avian Biol.
      34:3-15; and Barker, Cibois, Schikler, Feinstein & Cracraft (2004)
      "Phylogeny and diversification of the largest avian radiation" Proc.
      Nat. Acad. Sci. (Philadelphia) 101: 11040-11045 [I was able to downloand
      pdfs of each of these this week by doing "google" searches on the topic
      and/or authors' names].

      The short answer is that Sibley-Ahlquist-Monroe were half right and half
      wrong. Some stuff proved to be right on -- like the vireos are in the
      corvoid assemblage, which is why AOU moved them from next to warblers to
      their current spot some time ago. But Sibley-Ahlquist-Monroe also got a
      lot of stuff wrong. Most of these examples do not affect California
      birders, but the AOU swallowed several Sibley-Monroe claims that prove
      to be false (for just one example; AOU moved the South American
      Black-capped Donacobius from Mimids to Wrens on Sibley-Monroe grounds,
      but Donacobius is not related to either. It is a remnant taxa of Old
      World affinities -- maybe closest to babblers? -- rather than related to
      any New World familiy.

      As to the future, I'll go out on a limb and predict that the AOU will
      move New World Vultures back to their original place next to hawks
      (vultures do not appear to be storks as Sibley-Monroe thought); I expect
      the taxonomic position of Dipper to change (next to thrushes instead of
      next to wrens), the exact placement of waxwings and pipits may change
      (but perhaps not by a lot), and the sequences in
      tanagers/sparrows/cardinals will likely shift somewhat.

      These type of changes may await the 8th AOU Checklist, and that is some
      years down the line. The likely changes around the rest of the world are
      a lot more dramatic than they will be here.

      But no one should ever hope for complete stability in any checklist. We
      live in a time of particularly rapid change right now due to the
      emergence of new and better techniques that are capturing the attention
      of professional museum-based ornithologists. We are actually lucky that
      there is such interest and such a caldron of research and debate right
      now -- for decades ('60s, '70s, '80s) interest in taxonomic issues
      lagged seriously in ornithology. We are getting closer to some version
      of 'truth' about the details of avian evolution much more quickly now
      than ever before.

      I rejoice in all this new knowledge. I'm thrilled to rearrange the MTY
      checklist with better information. Incidentally, the on-line MTY
      checklist starting at
      http://montereybay.com/creagrus/MTYbirdlistportal.html is in the
      current AOU order, and Cackling Goose will soon appear there (plus new
      photos scattered about).

      And for perhaps something more directly related to CalBirds, see the
      latest news from Monterey County on rare birds at

      Don Roberson
      Pacific Grove CA
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