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Re: Morpho v molecular (was Re: Tinamous: living dinosaurs)



 mol-clock studies which claim a far older age nonwithstanding, the
 fossil record puts a lot of this radiation pretty damn close to the
 K-Pg boundary.

The molecular analyses are probably miscalibrated. That's very easy to do (Brochu 2004a, 2004b, 2006; Marjanović & Laurin 2007...). You need both old and young calibration points both inside and outside your clade of interest, and you need maximum ages for a few calibration points, or you'll get distortions. Calibration is not trivial work.

 So my main focus is whether partitioning can break the apparent
 convergence effect with owls, or whether the effect is simply too
 pan-bauplan.

Well, are you sure it's convergence? Mayr thinks it's not and points to animals like *Messelastur* as transitional forms.

 I'll try to include as many accipitrid fossils (and presumed
 accipitrid fossils) as my datasets allow me to. It'll be interesting
 to take a quantitative look at all that Paleogene/early Neogene South
 American material.

Yes yes yes yes!!!!

 "classical" LBA is simply molecular convergence on the macro level

Um, no. Long-branch attraction happens when a branch mutates so fast that its synapomorphies with other branches are overwritten, so there is not enough evidence left to place it with its sister-group, and it instead comes out at random -- next to (or closer to) another long branch with which it shares chance similarities, and the longest branch in any tree is usually at the root.

 I suspect the paleognaths in the Hackett et al. multigene phylogeny
 suffer from this: the topology is quite consensus if you unroot the
 paleognaths.

Maybe it's all their predecessors that suffered from this instead, and Hackett et al. and Harshman et al. finally got it right...! :-)

Wouldn't be the first time. It took till 2001 till somebody finally found the mice & rats as rodents and not as the sister-group(s!) to all other placentals anymore.

 But the "tinamous are secondarily volant" hypothesis suggested by
 their phylogeny stinks for obvious reasons (it violates everything we
 know about evolution of neoflightlessness in crown Theropoda).

But we all know that losing flight is much easier that regaining it. We aren't forced to pretend otherwise when optimizing that character onto a phylogeny. It has been suggested several times from morphological/developmentary evidence that flight was lost several times independently in paleognaths; here we finally have a phylogenetic hypothesis that fits this.

 Naive concatenation of multigene sequences is probably a Very Bad
 Thing

Why, when each gene is allowed its own model of evolution?