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Re: Senter 2004 - Renesto and Binelli 2005 (long)
Only branching order is informative in a cladogram, not necessarily
the order taxa are in from top to bottom. Remember, the tree above is
exactly the same as
or any other permutation of order you might think of that still retains
the same branching.
It should raise red flags for you when such specialized and highly
derived forms (rib gliders, tail hookers, plume raisers) are nested
(1) so close together without any demonstrated morphological
similarities and (2) without any linking taxa and (3) so close to the
base of a much larger and less well-endowed clade. You're putting the
Styracosaurus before the Psittacosaurus.
This contradicts the "understood" part. When cladograms are presented as
here or as in PAUP*, where the root is to the left, time progresses from
left to right, _not_ from top to bottom, _and_ it does _not_ progress with
the same speed along each branch. You're not putting the *Styracosaurus*
before or after the *Psittacosaurus*, you are putting them _next to_ each
Also, what is this talk of "without any demonstrated morphological
similarities"? The very fact that they appear as sister-groups in a
cladogram means that they have shared innovations.
Both Megalancosaurus and Longisquama show far too many derived
characters to ever be considered basal in any sort of logic.
There is no "basal". "Basal" means "farthest away from whatever I'm
interested in at the moment". Look at this:
When looking at this tree, it makes sense to say that the mammals are the
basalmost living amniotes.
Now look at this:
When looking at this tree, it makes sense to say that the birds are among
the basalmost living amniotes.
These two trees do not contradict each other. "Basal" is relative. Don't use
it as newspeak for "primitive".
More taxa create more resolution. Less 'by default' nesting'
Here I agree.