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Re: Most popular/common dinosaur misconceptions
But somehow the act of labeling
makes ness the seperation of the extinct dinosaurs and
the living brand. All of whom share common
characteristics that make them all aves.
Here, I fear, we have one more common misconception. When birds are
dinosaurs, they are still birds. The scientific name Aves does not get sunk
somehow. "Bird" and "dinosaur" are not mutually exclusive! When bats are
mammals, they are still bats: Chiroptera.
While I am at it, I should address yet another misconception: Phylogenetic
nomenclature and cladistics are not the same. Cladistics is the method to
find the most... scientifically defendable hypothesis on what a phylogenetic
tree looks like. Phylogenetic nomenclature is the method to label precisely
defined branches on a phylogenetic tree. There is no connection.
Well, there is one, but only historically. Willi Hennig, the entomologist
who invented cladistics, did so to have a method for making classifications;
he did not, as we do today, regard finding the tree as an end in itself. His
method of classification included naming only monophyletic taxa (those that
consist of an ancestor and all its descendants; Dinosauria, for example,
must either include the birds or be completely abolished, and Hennig would
surely have preferred the latter) and (from 1969 onwards) dropping ranks
(the kingdom-phylum-class-order-family business). These were the first steps
toward phylogenetic nomenclature. Phylogenetic nomenclature was invented by
cladists in the late 1980s, and I'm not aware of anyone who uses
phylogenetic nomenclature but does not accept cladistics, but these, too,
are historical coincidences, not necessities.
Nothing is limited to dinosaurs. Cladistics is universal today in most of
biology; notable exceptions constitute people who work on taxa with a very
rich fossil record, like conodonts or ammonites, some of whom still believe
that they can _see_ ancestor-descendant lineages by just _looking_ at the
fossil record. Phylogenetic nomenclature is still much more restricted,
primarily because most people simply don't know it; it is practically
universal among dinosaur workers today, but I don't think there are many
other such fields; there don't seem to be any entomologists who use it, for
example. Still, it is widespread -- people who work on flatworms, nemertines
(google Nemertini), sea slugs, sponges, polychaetes (bristleworms),
vertebrates, fungi, and plants use it, and so do some others.