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Re: birds and/or/with dino's
Mike Keesey <email@example.com> wrote:
> I have to agree with Mike Taylor -- a phylogenetic
> hypothesis should
> ideally not be part of a name.
Yet, we already do link many clade definitions with phylogenetic hypotheses.
For example, Saurischia is used for the dinosaur clade that includes Theropoda
and Sauropodomorpha, but not Ornithischia. Following Sereno (2005), the clade
Saurischia is defined such that it can only be used for the
Theropoda+Sauropodomorpha clade. Thus, clade Saurischia is explicitly tied to
the phylogenetic hypothesis that Theropoda and Sauropodomorpha are closer to
each other than either is to the Ornithischia.
If new fossil discoveries support a clade that includes Sauropodomorpha and
Ornithischia but excludes Theropoda, then the clade Saurischia ceases to exist.
However, the name Phytodinosauria is available for a
Sauropodomorpha+Ornithischia clade. Phytodinosauria would *only* be used in
the event of a Sauropodomorpha+Ornithischia clade being supported by
Thus, Saurischia and Phytodinosauria are each linked to separate phylogenetic
hypotheses that are mutually exclusive. Further, the names reflect the
individual phylogenetic hypotheses, based on traits inferred to be primitive
for each clade: Saurischia (propubic pelvis) and Phytodinosauria (herbivorous
> Isn't Condylarthra polyphyletic? (Or is that still being
> worked out?)
> Pretty sure Protozoa and Proteutheria are, too.
Even if polyphyletic, they were also paraphyletic given that they were the
putative basal members of much larger groups (Condylarthra-Ungulata;
Protozoa-Eukaryota; Proteutheria-Eutheria). Or I may have misunderstood you
here (if so, I apologize in advance)...
> The rest more or less
> correspond to clades which already had other names: Insecta
> (or Hexapoda),
Apterygota referred to the primitively wingless insects, so it would be
inappropriate to expand this group into a clade that includes *all* insects
(including the winged ones). Some entomologists have retained Apterygota for
the clade of primitively wingless ectognathous insects (such as silverfish)
that is the sister taxon to the winged insects (Pterygota), which are also
> Well, in that case it *would* be useful, as a name for the
> clade includng Cetacea and Artiodactyla.
Yes, I agree: Cetartiodactyla would be perfect for a Cetacea+Artiodactyla
> Something like this could work:
> Artiodactyla := Clade(Sus scrofa + Camelus dromedarius +
> Bos taurus)
> Cetartiodactyla := Clade(Balaena mysticetus + Sus scrofa +
> dromedarius + Bos taurus)
Yep, agreed. In your scheme, both Cetacea and Artiodactyla are restricted to
their respective crown groups, which is a neat idea. Other available names
could be used for the respective stem groups: Cete (stem-Cetacea; which would
include the raoelliids under Thewissen &c's phylogeny) and Paraxonia
> Then give the former precedence if they turn out to be
> heterodefinitional synonyms. (Mmm, cinnamon.)
Thanks - now I have a donut craving....