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Re: Turtles and Crocodylians are not Reptiles - no? What are they?
On Thu, Jul 24, 2008 at 8:45 PM, Tim Williams
> If turtles and crocs are being drawn together by long-branch attraction, and
> neither birds nor
> squamates can break this up, then all other options are exhausted.
Well, as I said few clades is not a big problem per se, it could be
problematic if there are many homoplasies - long-branch attraction is
an artifact resulting from homoplasies. It could be reduced by some
>> My fault here. Normally "fossil" DNA reffer to a conserved DNA
>> sequence - somewhat molecular fossil - it could help in somecases. But
>> what I've meant is what Boehm said: DNA preserved in fossil.
> This hasn't happened yet (for fossil vertebrates, anyway), except for certain
> subfossil taxa.
Yes, that is the reason for I have said *eventually* and in parentheses.
>> Closer to hippos thant to mesonychids anyway.
> Actually, no. Under Thewissen &c's phylogeny, there is a 3-way polytomy
> composed of Mesonychia, _Andrewsarchus_ and the Cetacea+Artiodactyla clade.
> hippopotamids are inside the crown Artiodactyla, in the Suina clade. Because
> the whales
> are recovered in a Cetacea-Raoellidae clade at the base of the Artiodactyla,
> cetaceans are
> *not* closer to hippos than to mesonychians. Not according to this
> phylogeny, anyway.
As Pharris and Keesey noted, *closer* in a phylogenetical/hennigian
context: shared the same evolutionary history for a longer time.