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Re: Blogging SVP



On Thu, Oct 31, 2013 at 9:31 PM, Tim Williams <tijawi@gmail.com> wrote:
> Mike Keesey <keesey@gmail.com> wrote:
>
>> (Well, as near as I can make it out, he puts
>> some other things closer to bats, like colugos and pen-tailed
>> treeshrews[!] and African palm civets[!!!], but....)
>
> But indeed.  I can readily believe that arctocyonids and
> phenacodontids are paraphyletic (or even polyphyletic).  Not crown
> Scandentia or Carnivora though.

Minor correction -- he has Nandinia in Carnivora (sensu stricto),
outside the Chriacus + Chiroptera clade. But he also seems to consider
it an ancestral form for that clade.

Needless to say, his topology goes very much against what molecular
studies have shown (or any other morphological study for that matter,
in splitting Primates and Tupaiidae from other "archontans" -- yes,
polyphyletic Scandentia). But maybe it's worth it to have a look at
Protictis?

>> It involved an arbitrary character-based distance metric that also
>> revived Elosaurus. (No less arbitrary than the usual decision,
>> though.)
>
> Unless _A. ajax_, _A. excelsus_, _A. louisae_, and _A.parvus_ do NOT
> form a monophyletic group to the exclusion of other diplodocids, there
> doesn't seem any point to reviving _Elosaurus_ - or _Brontosaurus.

I agree with you there. If he'd changed his "generic distance" to 15
characters instead of 10 (which he admitted was arbitrary and only
pertained to that particular analysis, not to be used as a general
rule) it'd probably come out that way, as well as sinking some
diplodocine genera.

-- 
T. Michael Keesey
http://tmkeesey.net/