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Occam's bulldozer, part 2: Ernst Mayr & Walter Bock



Ernst Mayr & Walter J. Bock, 2002
Classifications and other ordering systems.
Jour. Zoological Systematics & Evolution 40(4):169-194
A survey -- uneven, flawed in places one would not
expect it: their rejection of cladistics, in the main,
precipitates a sense of bewilderment, as they embrace
a taxonomic template of no use to sorting through,
e.g., the phylogenetic systematics of dinosaurs, or
the plastid and nuclear DNA sequences which enable
scholars, now, to finally achieve a complete
understanding of the relationships of all living
dinosaurs. Their idea of a "Darwinian classification"
is, like a bubblegum wrapper, colourful but riddled
with wrinkles and permutations. Darwin, of course, was
not a taxonomist (plagiarist, yes [cf. May-June
1858]), and for them to propose that, in effect,
Hennig's work is not a classifacatory is not true.
Higher level phylogeny is fraught with difficulties,
but  can, with molecular DNA data, be explicated. The
interrelationality of genera (converted clade names)
is, to be sure, the source of research, discussion,
disagreements.
I have read this paper twice, each time realizing
these scholars are exhaling the frantic struggles of
the "death" of Linnean taxonomy, which, like a warm
womb, offers comfort if nothing else. The principles
of phylogenetic taxonomy are firmly based in the
tenets of evolution: 1)plastid and nuclear DNA
sequences, when available; 2)a data matrix of
character states analyzed using PAUP 3.1.1. (with
heuristic search options, pending powerful computer
networks so that Branch-and-Bound and Exhaustive
search methods [unfortunately such networks of
computers are governmentally monopolized in efforts to
construct weapons]); 3) trees of parsimony
subsequently analyzed with MacClade 3.07, in turn
accelerated (ACCTRAN) and delayed (DELTRAN)
transformation optimizations clarifying distributions
of character states [I am here freely using the
framework elucidated by Thomas Holtz in his A new
phylogeny of the carnivorous dinosaurs]). Neither
Ernst Mayr nor Walter Bock have ever published a
scientific paper using the modern scientific
techniques of #s 1-3.
I am quite familiar with the ornithological work of
both Ernst Mayr and Walter Bock, the latter in
particular having written papers which created the
concepts of ecomorphology and form-function complexes
I find useful in inferring the behavioural strategies
of the Mesozoic feathered, flying and secondarily
flightless, theropods. The bulk of Ernst Mayr's
ornithological papers are descriptive, his
establishing of new genera often based on (how else to
say it?) colours of avians, but never on what DNA data
would reveal.
Nelson and Plotnick, over 20 years ago, iterated the
idea of taxonomy reflecting "propinquity of descent" =
Hennig's 1966 "monophyly". Thus, phylogenetic
systematics, in contrast to the Mayr/Bock yearning for
something which is not, to be frank, especially fluid
in response to new data (cf., the endless semantic
tap-dancing of those who have classes, subclasses,
oidea, idae, inae, tribes, families...in effect, a
plethora of usually not defined names), is the path of
21st century evolutionary developmental biology (of
which dinosaurology is a part). When studying, for
example, the interrelationships of "ceratosaurs", we
are interested in discovering the "ancestor" of later
lineages of theropods, and it is this which IS the
basis of taxonomy: ancestry systems consisting of an
ancestor and its subsequent lineages. The "Darwinian"
classification of Mayr/Bock, despite its claims, is
not especially based on rigorous analyses of
evolutionary processes. All taxa, then, are clades or
species names, based on node-, stem-, or
apomorphy-based names [I am following the outline of
the ideas from Julia Clarke's cogent dissertation].
Tyrannosaurus, e.g., is a "specifier", the taxon used
in the definition of the clade name Tyrannosauridae,
both Tyrannosaurus and Tyrannosauridae defined using
#2 and #3 above.

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