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Re: At long last! Turner, Makovicky & Norell on dromaeosaurids



"As we have discussed earlier,  we view it as problematic to include
> *Epidendrosaurus* in a phylogenetic analysis because of the extremely
> poor level of preservation, which results in much missing data, and
> the likely juvenile status of the holotype specimen. Our exploratory
> analysis reinforces this latter point. All three recovered
> synapomorphies are subject to ontogenetic changes and the observed
> morphology and proportions of the holotype of *Epidendrosaurus* may
> very well be different from its adult phenotype. [...]"

Synapomorphies of *Epidendrosaurus* and what?

Oh, do they mean _aut_apomorphies, like they do in the quote below about Jinfengopteryginae?

*Bambiraptor feinbergi*  (incorrectly written as "feinbergorum")

How many people is it named after?

"*Jinfengopteryginae*, new  clade name ... We name this new clade of
> troodontids for two reasons. First, the clade represents a distinct
> group that is the sister taxon to nearly all other troodontids,
> therefore having a specific name for this group serves a practical
> purpose in discussions of troodontid relationships and evolution.
> Second, the clade possesses strong character support (six unambiguous
> synapomorphies) and high jackknife support, rendering it relatively
> stable. A stem-based clade name was chosen in order to provide a
> taxonomic framework for additional troodontid taxa that may be found
> or are undescribed and prove to be close relatives to this basal
> troodontid clade." - Turner et al. 2012:pg.107.
>
> It's fine to name the taxon, if you need to. But it seems to read
> that "-inae" is a useful form to name stem-based clades; but also
> that "stem-based" is a reference to the definition: the form of the
> clade NAME should have nothing to do with the formulation of the
> name. This is a holdover from the rule or convention of using "type
> species" to name ranks, but also a small group of PhyloCoders who
> argue that the NAME form should follow the TYPE of clade definition
> it is being applied to, so that stems, nodes, crowns, etc. would all
> have little labels or formulation.

Uh, no, I don't know of any such group.

What I know is of highly influential people (Gauthier, de Queiroz...) who put a lot of emphasis on crown-groups and total groups. They want to use basic names for crown-groups, form the names of total groups by adding the prefix *Pan-* (with the hyphen, and with retaining the following capital letter), and form the names of apomorphy-based clades -- in cases the name refers to an apomorphy -- by adding *Apo-*. So, *Spermatophyta* would be a crown-group, its total group would be *Pan-Spermatophyta*, and the first seed (Greek: _sperma_) plus all its descendants would be *Apo-Spermatophyta*.

All jinfengopterygines are dead, so the above paragraph does not and cannot apply to them. Turner et al. apparently want to retain hierarchical information: they want the name Jinfengopteryginae to have some indication that it is part of some clade whose name ends in -idae. Fine, but with the potential of major confusion when the phylogenetic hypothesis changes.

This issue floats around a bit,  and even Wikipedia jumps in on it,
> where *Jeholornis prima* is considered to be the correct name for
> both taxa, when synonyms.

Oh, I need to fix this, because there has never been a *Jeholornis prima*. _Ornis_ is a he, not a she; it's *Jeholornis primus* Zhou & Zhang, 2002, even though Zhou & Zhang have never spelled it that way. The ICZN is almost clear on this (uncharacteristically): the correction is automatic, no emendation needs to be published, and the corrected spelling must be attributed to the original authors (not, for example, to the authors of any unnecessary emendation).

"21.7. Date not specified. If  the date of publication is not
> specified in a work, the earliest day on which the work, or a part of
> it, is demonstrated to be in existence as a published work is to be
> adopted as the date of publication of the work or of that part. In
> the absence of evidence as to day, the provisions of Article 21.3
> apply."
>
> No date was forthcoming. The wrinkle comes when you consider that, if
> there was an explicit reference to date of publication or a
> demonstration of availability, then _that_ date takes precedence over
> the ambiguity of the print form. This date comes via George
> Olshevsky, who reported (http://dml.cmnh.org/2002Nov/msg00292.html):
>
> "But there is proper evidence, in the form of press releases and
> Chinese news articles dated July 23, 2002 (China Daily), that
> Shenzhouraptor appeared in print at least two days before
> Jeholornis."
>
> That date can be linked directly
> (http://www.chinadaily.com.cn/en/doc/2002-07/23/content_129001.htm)

It only says: "The scientists' research findings were published in this month's issue of the Geological Bulletin of China". It doesn't explicitly say that anything was printed. Did that journal publish online-early in 2002?

If it did not, you're right, and *Shenzhouraptor sinensis* has priority over *Jeholornis primus*.

Several of these characters  have a broader distribution, but also
> occur in the "outgroup" oviraptorosaurs (e.g., *Caudipteryz zoui*,
> *Khaan mckennai*, etc.) and thus should have no real bearing on the
> cohesion of the taxa in question;

That depends. Are they optimized as reversals?

lachrymal

Lacrimal (_os lacrimale_, "tear bone"), from Latin _lacrima_ (preclassical _lacruma_), "tear". The Greek for that is _dakryma_, with the exact same unaspirated /k/ and without the occasional Latin shift from /d/ to /l/ (as in _lingua_, or in _Ulixes_ from Greek _Odysseus_).