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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.