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