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Date: Sun, 02 Feb 2003 12:16:48 -0500 (EST)
From: StephanPickering@cs.com
To: qilongia@yahoo.com
Cc: PhyloCode@ouvaxa.cats.ohiou.edu
Subject: Re: New Dinosauricon Taxon Pages: _Therizinosauria_
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Alas, Qilongia's tortuous semanticism obscures the fundamental reality
of evolutionary processes: new species arise from both hybridization and
mutations (among other factors). Natural, not experimental, hybridization is
a fulcrum of much speciation, as the work of R.G. Harrison explicates.. His
definition is worth noting, that hybridization is successful matings between
conspecific "individuals from two populations, or groups of populations,
which are distinguishable on the basis of one or more heritable characters".
Such successes, by definition, are fertile F1 progenies (contrary to what
many may think, hybridization is not uncommon in "nature"), i.e., are the
offspring of matings between individuals of two populations, groups of 3+
populations, these offspring passing synapomorphies to further generations.
Thus, this means that natural hybridization = reticulation = reticular events
= reticulation. These matings occur in what are termed "hybrid zones", the
intergradation of breeding individuals (cf. J.A. Endler's still useful 1977
study Geographic variation, speciation, & clines). In other words,
hybridization has both very real biological implications for breeding
populations of taxa, and taxonomic permutations.
So, too, does the process of mutation within the contexts of
ecophenotypicism and (bio)phenomenological factors. Hugo de Vries called
"mutational" variations "species", an individual with a genomic structure
similar to, but different from, phenotypes. Although dated and mistaken on
many levels, de Vries's 1889 Intracellular Pangenesis contains
conceptualizations of cellular processes remarkably similar to what is now
known (and inferred) about speciations, his "pangenes", of course, being
dominance/recessive alleles. Mutation, thus, is the logical isotropy of life
on the edge of chaos, mutations being what Stephen Jay Gould terms "spandrels
at the oranismal level".
A final note: it is premature to establish Therizinosauria, a
phylogenetically redundant name (the goal of phylogenetic systematics is
clarity, not obfuscation). The ongoing plethora of redundancy, as it relates
to post-K/T Theropoda ( i.e., "birds"), is in the long overdue process of
being revised on the principles of anatomical analysis and phylogenetic
systematics by Bruce Livezey. Pre-K/T dinosaur taxonomy is, in the main,
being stabilized, with certain clade names in need of clarification (i.e.,
conversions). In particular, the "therizinosaurs" are long-necked, poorly
known theropods of uncertain taxonomic position within the converted clade
name Coelurosuria. Thomas Holtz's 2000 and 2001 theropod taxonomies were
unable to resolve their synapomorphies (Therizinosaurus itself is barely
diagnostic if one ignores the suite of characters found in other, more
complete taxa). As with his discussions re: taxonomies of the feathered,
flying and secondarily flightless, theropods, Qilongia displays a lack of
familiarity with the literature.
--Boundary_(ID_zlc4vLaoN4r0ayUavSVGaQ)
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Alas, Qilongia's
tortuous semanticism obscures the fundamental
reality of evolutionary processes: new species
arise from both hybridization and mutations
(among other factors). Natural, not
experimental, hybridization is a fulcrum of much
speciation, as the work of R.G. Harrison
explicates. His definition is worth noting, that
hybridization is successful matings between
conspecific "individuals from two
populations, or groups of populations, which are
distinguishable on the basis of one or more
heritable characters". Such successes, by
definition, are fertile F1 progenies (contrary
to what many may think, hybridization is not
uncommon in "nature"), i.e., are the offspring
of matings between individuals of two
populations, groups of 3+ populations, these
offspring passing synapomorphies to further
generations. Thus, this means that natural
hybridization = reticulation = reticula
<BR> So,
too, does the process of mutation within the
contexts of ecophenotypicism and
(bio)phenomenological factors. Hugo de Vries
called "mutational" variations "species",
an individual with a genomic structure similar
to, but different from, phenotypes. Although
dated and mistaken on many levels, de Vries's
1889 <I>Intracellular Pangenesis</I> contains
conceptualizations of cellular processes
remarkably similar to what is now known (and
inferred) about speciations, his "pangenes", of
course, being dominance/recessive alleles.
Mutation, thus, is the logical isotropy of life
on the edge of chaos, mutations being what
Stephen Jay Gould terms "spandrels at the
oranismal level".
<BR> A final
note: it is premature to establish
Therizinosauria, a phylogenetically redundant
name (the goal of phylogenetic systematics is
clarity, not obfuscation). The ongoing
plethora of redundancy, as it relates to
post-K/T Theropoda ( i.e., "birds"), is in
the long overdue process of being revised on the
principles of anatomical analysis and
phylogenetic systematics by Bruce Livezey.
Pre-K/T dinosaur taxonomy is, in the main, being
stabilized, with certain clade names in need of
clarification (i.e., conversions). In
particular, the "therizinosaurs" are
long-necked, poorly known theropods of uncertain
taxonomic position within the converted clade
name Coelurosuria. Thomas Holtz's 2000 and 2001
theropod taxonomies were unable to resolve their
synapomorphies (<I>Therizinosaurus </I>itself is
barely diagnostic if one ignores the suite of
characters found in other, more complete taxa).
As with his discussions re: taxonomies of the
feathered, flying and second
--Boundary_(ID_zlc4vLaoN4r0ayUavSVGaQ)--