Let’s take out all Solnhofen birds except Archaeopteryx from the LRT

Figure 1. Theropod subset of the LRT focusing on birds and bird mimics. Only one Archaeopteryx, the holotype, nests here with Enantiornithes.

Figure 1. Theropod subset of the LRT focusing on birds and bird mimics. Only one Archaeopteryx, the holotype, nests here with Enantiornithes.

Traditional cladograms include
only one Solnhofen bird, typically labeled Archaeopteryx. Whether they use the holotype specimen or not, I don’t know. Earlier the large reptile tree (LRT, subsets Figs. 1, 2) added several Solnhofen birds, many workers continue to call Archaeopteryx, while others have given new generic names. A recent paper by Wang and O’Connor 2017 on pygostyles brought this subject back to the table. They recovered four different sorts of pygostyles, but did not recognize four convergent origins for the pygostyles due to (I thought at the time) lacking more than one Archaeopteryx specimen. It’s time to test that assertion.

As reconstructions show
the variety of Solnhofen birds has been largely, but not completely overlooked. In any case the variety is certainly apparent and a revision of the genus Archaeopteryx is long overdue given the interest in every new specimen.

So, what happens to the LRT when only one Archaeopteryx (the holotype) is employed?

< See figure 1.
There is no change in the tree topology, other than the loss of six Solnhofen bird taxa (Fig. 2). The holotype Archaeopteryx continues to nest within Enantiornithes, an extinct bird clade.

Taxon deletion is a good test

Figure 2. Subset of the LRT with seven Solnhofen birds included.

Figure 2. Subset of the LRT with seven Solnhofen birds included. Note their basal positions in the several basal bird clades. This chart, by implication, demonstrates that the first birds preceded the Solnhofen Formation.

Having seven Solnhofen birds
in a cladogram illuminates the origin of birds, the origin of enantiornitine birds, the origin of scansoriopterygid birds and the origin of ornithuromorph birds all from Late Jurassic Solnhofen taxa, something we haven’t had until this point. This is what Wang and O’Connor 2017 lacked and so their report on pygostyles was unnecessarily incomplete.

I encourage all bird workers
to include as many Solnhofen birds as possible in their phylogenetic analyses, and for at least one of them (hopefully more) to revise their taxonomy to include more genera. That would make a great PhD thesis.

References
Wang W and O’Connor JK 2017. Morphological coevolution of the pygostyle and tail feathers in Early Cretaceous birds. Vertebrata PalAsiatica 2017:10: 55:3: 1-26.

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13 thoughts on “Let’s take out all Solnhofen birds except Archaeopteryx from the LRT

  1. I encourage all bird workers
    to include as many Solnhofen birds as possible in their phylogenetic analyses

    …after filtering out the ontogenetic variation. I’m not saying all of the differences between the specimens are ontogenetic, but some pretty clearly are.

    • Almost all of the differences between them in Peters’ matrix are fictional, not ontogenetic. Look up some of his reconstructions on this blog and you’ll see they don’t resemble the actual specimens closely at all.

    • Stop refusing to accept the fact that “ontogeny discombobulates phylogeny”. There’s literature on that, and you know it.

      If you don’t filter out the misleading signals, your tree will be misled. It’s as simple as that.

      Besides, I’m a postdoc. It’s not like I had an army of grad students at my disposal to do your job.

  2. I choose to go with the data, unfiltered, rather than guess which traits need to be filtered and how. So far I’m getting gradual accumulations of traits and occasionally overturning false paradigms. You don’t think I should bias the data, do you?

    • You don’t think I should bias the data, do you?

      You’re committing a logical fallacy here. Read up on ontogeny and phylogeny. Wiens et al. (2005) is in Systematic Biology, so it’s in open access, and that’s just the tip of the iceberg. There’s fascinating work on ontogeny and phylogeny in ceratopsids, with applications for everything else!

    • Oops, hit Post too soon.

      So far I’m getting gradual accumulations of traits

      So does everyone. That’s really hard to avoid, you know. And the more taxa you have, the more gradual it’ll be, no matter how wrong the tree is.

      and occasionally overturning false paradigms

      How do you know they’re false?

      Hint: you don’t.

  3. False: Everyone does not always get gradual accumulations of traits. That’s why the pterosaur workers keep claiming they appear ‘out of nowhere’.

    And what’s with the pugnacious attitude? This is not a ‘behind the barn fight.’ You’re not a bully, David. Put your lab coat back on and act like a scientist.

    • The sad part is that I am acting like a scientist – and you’re not. I’ve been trying to explain phylogenetic analysis and the nature of the fossil record and several other things to you for at least twelve years now, including in several comments here (mostly this month); rather than trying to learn how all that works, you simply assume – unlike a scientist – that you understand everything important already and have nothing left to learn.

    • …and then you claim that the LRT resolves the relationships “correctly” without correcting almost any of the problems in the matrix Jason and I have pointed out.

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