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Re: paper on drepanosaurids + woven bone ps
> This cladogram seems to use suprageneric taxa (Tanystropheus includes? or
equals? Protorosauria) (Gephyrosaurus equal Lepidosauria) etc. which Dr.
Unwin has already warned us about in 2003. Better to use museum inventory
*Gephyrosaurus* is just *Gephyrosaurus* (a Triassic sphenodontian). It
happens to be the only included lepidosaur(omorph), so it is thought to
indicate where the position of Lepidosauromorpha is in that cladogram. This
method is the opposite extreme from using composite OTUs (which would be to
infer the ancestral state for Lepidosauria from some other cladogram and
code that as an OTU).
Of course, the addition of further lepidosaur(omorph)s could change
that. But we can't assume that a priori without testing it.
> Clarification: woven bone: this is not a strict basket weave, as in
looping under or over, but as others have noted and described it as, more of
a plywood effect, layers of cross grained patterns -- in the adult. In my
opinion this is the end result in the mature bone of solidification and
multiplication of a simpler single, double then triple layered cross-grained
pattern in neonates. The basket weave effect would be (hypothetically)
achieved in juveniles via cellular adhesion of one layer with another as
layers are added.
I still don't understand. Are you talking of something else than
fibrolamellar bone? Are you talking of something that's not seen in Padian