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RE: Two questions on the dino-fleas
Just to clarify, the term is "microraptorians."
*Microraptoria* was named by Senter specifically as a non-ranked clade name.
Despite this, use of "microraptorines", "Microraptorinae" and so forth has
persisted despite attempts to clarify. It does not help that Longrich & Currie
thoroughly abuse the heck out of "Microraptorinae" while attributing this to
Senter, when Senter coined a different name entirely. So when Wikipedia
redirects links to *Microraptoria* to
http://en.wikipedia.org/wiki/Microraptorinae, even going so far as to cite
Longrich and Currie (in naming *Hesperonychus elizabethae*) for a
"Microraptorinae" within "Microraptoria" you tend to think they are actually
supported in this action, but clearly skipped over the specifics on this point.
Specifically, this is Senter, Barsbold, Britt and Burnham (2004; pg.7):
"The sister clade to Dromaeosauridae *sensu stricto* is speciose enough to
warrant its own generic name. We therefore introduce the name Microraptoria,
defined as the clade of taxa that are more closely related to Microraptor than
to *Velociraptor* or *Dromaeosaurus*. We have deliberately avoided the suffices
"=idae" and "-inae" for this name. Under a phylogeny in which Troodontidae and
Dromaeosauridae are sister taxa, and Sereno's (1998) nomenclature has priority,
"Microraptoridae" would occur within Dromaeosauridae, engendering confusion by
yielding the appearance of a family within a family. Under the phylogeny
recovered here, "Microraptorinae" would occur outside any taxon with a name
ending in "-idae", engendering confusion by yielding the appearance of a
subfimily without a family."
Longrich and Currie, rather, consistently use "Microraptorinae" where Senter
et al. provided for "Microraptoria," even citing Senter on the nomenclature.
I'd rather approach this as a _lapsus_ rather than a fault, and suspect they
meant to use Senter's word but were understandably mistaken on its treatment
due to the unusual case of placing a non-ranked clade name within a "family"
grouping of taxa.
I note that similar issues correspond to the effect of further phylogenies
shuffling around taxa like *Unenlagia comahuensis* and its apparent sister
taxa, and their relationship to troodontids, dromaeosaurids, or even specific
subgroupings of the latter "collective" (which i note here under the "family"
name merely due to gradient). Under the ICZN, this is not a problem, since the
convenience is that a systematist who first names one Family-rank taxon names
ALL of them, meaning there is always a convenient name available. There is a
further problem, in that occasionally, you get "subfamilies" in families that
do not contain taxa not contained by another "subfamily," an effect that has
resulted from the argument that certain ranks with diagnoses are true always
(until otherwise defined), meaning you can pretend that a "family" is true only
for a subset for which it is initially built to include.
I recently mentioned this problem with regard to "a new family of amphibians"
(the conversation about this starts here:
http://dml.cmnh.org/2012Feb/msg00204.html, is replied to by Marjanovic here:
http://dml.cmnh.org/2012Feb/msg00205.html, and persists until here:
http://dml.cmnh.org/2012Feb/msg00209.html). The issue, perpetuated in the
original literature, is that there is a concept of a "fixed" idea for a clade
name with attached to a rank -- it is, in fact, the only way to justify the
existence of ranks: to agree that the diagnosis or definition will always be
true ... unless, of course, someone wants to "revise" it.... This seems to be a
mentality, a sort of "Linnaeism," that decides a rank must exist, and enforces
this on nomenclature regardless of the existence of a counterargument, or even
in defiance of the original argument (as in Longrich and Currie's discussion).
The way things were done before is not tenable. The changing world requires
that we find ways to talk about groups of taxa that we cannot simply shoehorn
into classic ranks or subranks. There simply aren't enough of them, despite the
attempts of some to go overboard in applying various prefixes or suffixes to
other names in order to "rank" everything. They'll run out of those. The
alternative, while staying in rank-land, is to simply ignore the issue (as when
dealing with diversity in and among "species groups"). Removing ranks removes
this problem: if a node or stem is useful to discuss, name it, use it, and move
Senter, P., Barsbold R., Britt, B. B. & Burnham, D. A. 2004. Systematic and
evolution of Dromaeosauridae (Dinosauria, Theropoda). _Bulletin of Gunma Museum
of Natural History_ 8:1-20.
Longrich, N. R. & Currie, P. J. 2009. A microraptorine
(Dinosauria--Dromaeosauridae) from the Late Cretaceous of North America.
_Proceedings of the National Academy of Sciences, Philadelphia_
Jaime A. Headden
The Bite Stuff (site v2)
"Innocent, unbiased observation is a myth." --- P.B. Medawar (1969)
"Ever since man first left his cave and met a stranger with a
different language and a new way of looking at things, the human race
has had a dream: to kill him, so we don't have to learn his language or
his new way of looking at things." --- Zapp Brannigan (Beast With a Billion
> Date: Sat, 17 Mar 2012 23:54:34 -0400 >
From: firstname.lastname@example.org > To:
email@example.com > Subject: Re: Two questions on the
dino-fleas > > > On Thu, 15 Mar 2012
20:46:07 +0100 > "David Marjanovic"
<firstname.lastname@example.org> wrote: > > > And
further, that fleas became smaller, and started jumping, as an >
> > adaptive response to dense body-coverings? >
> > > *lightbulb
moment* > > Just as the microraptorids would
start gliding out of trees when > acting as groomers and using a
stiff tail to flip clear of the feet of > their host when
detaching. > > A large and highly pointed claw makes
for a relatively poor climbing > crampon on bark, but should work
well on hide and integument. One might > even be able to dig
enough of a gash to get some blood (if one wanted > to move
from symbiotic to parasitic feeding)... > > The
true origin of flight...? > > -Jonas