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re: theropod phylogenetics paper
Let us try once again for those who can't follow the equation: crown dinosaurs > feathered dinosaurs > flying dinosaurs. One cannot define "bird" apart from "dinosaur" A footnote: those would obfuscate the question by referring to other lineages should stop; humans are primates, highly derived from either a mutated group of chimpanzees, or from a clade from which chimpanzees and hominids are derived. I choose to not to define extant humans as chimpanzees or apes or lemurs, etc., regardless of the fact that, in informal usage, humans are "apes". Again, we are talking about clarity of words; perhaps extant humans are a form of chimpanzee, but, until the evidence is discovered, I lean toward the hypothesis chimps and humans are from the same clade. At the moment, the origins of extant humans relative to extant chimpanzees (our closest living relatives) are ambiguous, unless, to be sure, a chimpanzee fem!
ale can be hybridized with a human male, or a human female can be hybridized with a male chimpanzee, and the offspring is fertile.
Although I have read ill-formulated criticisms of it, the Gauthier/de Queiroz paper on "Aves" is a masterful overview and clarification. So: is a "bird" a "dinosaur", and a "dinosaur" a "bird"? Of course. A small number of feathered theropods survived the K/T (Jim Carey's work coupled with Graham Martin's unfolding discoveries re: ultraviolet vision are intimations of what will, perhaps, be another way of understanding how they did survive the conflagration)...correction: I should write "feathered theropod dinosaurs" (not all of them were winged flyers). How quickly one can forget that it was Percy Lowe (a name quite familiar to John Ostrom) who saw Archaeopteryx as a theropod. Let me restate the obvious (I am drawing from both the Gauthier/de Queiroz paper and Jacques Gauthier's 1984 dissertation, the latter subsequently revised in 1986 [and still a good "springboard" for discussion]): Aves cannot be separated from the crown clade of !
Dinosauria. Unambiguous definitions of each interlinked clade, as enunciated by Gauthier/de Quieroz provide one with unambiguity, Avialiae containing those taxa with feathered wings capable of flight because possession of feathers is not an indicator a dinosaur could fly. Are the "birds" around us still dinosaurs? Of course. And it is my personal choice to, as much as possible, in my book and on the List, use dinosaur and not "bird". For the latter, "living winged dinosaurs" is accurate enough in informal discussion (the extant ornithuraen clade also). Thus, as much as I enjoy being educated by his ongoing work, I disagree with S.J. Gould: "birds" are living winged dinosaurs who survived and radiated in amazing ways for 65 million years since the K/T impact. There are List members who seem upset with the use of "dinosaur" for "bird". Let them present an unambiguous hypodigm of defined clades, taking into account characters. They will end up with a mirror of the Gau!
thier/de Queiroz paper. They did not attempt to answer the multitude of queries re: relationality among known fossil theropods from the Mesozoic, especially between the various feathered theropods, feathered theropods who could possibly glide/flap, etc.
So, the next time one sees a pigeon or duck or crane, one is seeing a living ornithuraen dinosaur.