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Re: questions about the Odontochelys study
D. Marjanovic wrote:
<< as wondering which species the authors used when they say that
turtle blood tests link them with 'diapsids'?
Several. Also, not just any diapsids: either as the sister-group of
Archosauria or as the sister-group of Crocodylia.
And a phylogenetic analysis of sequence data is not a "blood test".>>
Confirming the sequence data, which characters can we look to as
synapomorphies between crocs (or any other archosaur) and turtles?
<< Was wondering which species Rieppel used when he linked turtles
to lepidosaurs or squamates and sauropterygians?
Mostly *Proganochelys*, IIRC. >>
Which species on the non-turtle side of the equation?
<<(Which, incidentally, is not trivial to interpret. Kordikova 2002
claims to have discovered postparietals and tabulars in the skull,
both never seen before and both supposed to be absent.) >>
Is Gaffney's interpretation of the skull gospel? And if so, which
outgroup did Gaffney use to decide which skull bones were 'as is' and
which were the product of fusion?
<< How many millions of years link turtles to their closest known
Depends on what those are, obviously. Euryapsids appear sometime
around the Early-Middle Triassic boundary, lepidosaurs in the Middle
Triassic, crown-group archosaurs around the Early-Middle Triassic
boundary (probably earlier), procolophonoids in I think the Late
Permian, and pareiasaurs in the Middle Permian. >>
Is there enough time for the evolution of the carapace in each of
these groups? Can we eliminate some possibilities due to lack of time?