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Re: More on Argentavis



The hardest thing is not to get overwhelmed by
evidence. Having a hand-list of blanks - like Robert
T(IIRC)'s idea of "list of sites which *lack* key
fossils one would expect" - helps too.

This, of course, would still need to come with a blanket disclaimer. The Morrison Fm has been worked on more or less continuously ever since Marsh and Cope. When was the first ankylosaur found there? In the 1990s. Now we have two "genera" from there, and we are talking about newly dug-up specimens, not about reidentifications of museum drawer material. Surprises happen.


_Limenavis_ for example is useful as an outgroup
that's very close to the interesting bits.

If only it weren't just a fragmentary wing...

(If one is really extreme, _Gargantuavis_ cannot miss
;-) If one wants to add that... thing..., one might
just as well throw in _Patagopteryx_ - if anything
groups with *that* unduly often, you'll know a
character needs to be refined or removed.)

The other way around: you know that you need to _add_ characters and/or taxa.


Might even help pinpointing promising strata.

The limiting factor on new discoveries is not the availability of strata, it's the number of paleontologists in the world...


I have checked on the molecular studies since the data
started to become good (ancient DNA, decent-length
sequences) and *something* is odd about it. Can't lay
my finger on it... might be a bad signal-noise ratio,
might be an apomorphically altered metabolism adding
noise, or whatever. Still, the moa sequence
divergence, which should be comparable with with crown
taxa, is odd. Morph/mol evolution rates don't seem to
match up. Massive genetic drift, with Taupo volcano
blowing up ever so often again? I don't know...

I don't understand. Please explain.

See e.g.
here: http://www.indiana.edu/~geol116/week7/plates.jpg
for the interesting relationships between
Indo-Australian and Pacific plates around Fiji.

I don't think that's what you mean. It shows no details smaller than the existence of the Juan de Fuca plate.