Related to another thread, I believe Cece made a small boo-boo. Of course it was not in the main thread, but… In “Triumph…” pg 215, “-in short, birds are dinosaurs.” OK, let us accept as a given that birds did descend from the dino’s, why does that make birds dinos? After all, humans descended from an early lemur like creature, but we are not lemurs. Birds are suff. different from dinos to rate their own class, even if they are related.
Bakker, having come up with some brilliant ideas, can’t let the birds=dinos thing go, even to the point of remarking upon seeing geese fly south “There go the dinosaurs, flying south for the winter”. BS!
Saying “birds are dinosaurs” is fully as correct as saying “primates are mammals”.
We are not saying that one given species is a member of a group of related species, as in your “humans are lemurs” example. That would be more like saying “herring gulls are albatrosses” and that makes no sense.
The column in which Cecil Adams said "birds are dinosaurs is this one:
What differentiates dinosaurs from other lizards? Week of: 30-Jun-95
No, avians are not a order or subclass of Dinosaurs. It MAY be that birds descended from dinos, but even so, reptiles decended from amphibians, and mammals from reptiles. Still, mammals (or humans or lemurs) are not reptiles, nor are lizards amphibians. Remember Kingdom, Phylum Class Order Family Genus Species!
Note that all of these classes are chordata, ie vertebrates. So Humans, lemurs, dinos, AND birds are all vertebrates. Some arguement that dinos ( of several classes) and avauns are all members of a “superclass” can be made, but they are still different classes.
Birds are not dinosaurs!
Thanks, Arnold. very heplful. (this is not sarcasm)
Taxonomy is not some type of Ultimate Truth ™ handed down from Mount Parnassus. Classifications can be and are revised as new information is found.
Now, it is clear that several lines of dinosaur had feather or feather-like coverings. The only line of dinos who made it past the Cretaceous extinction event happen to be those which fly. If something happened to cause the extinction of all mammals except bats, would that make bats “not mammals”?
Birds are dinos by any criteria, despite being the only living members of the dinosauria.
Having worked for over a decade in the natural sciences, I feel qualified to offer the following 4 cents, which you may consider for your amusement:
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There’s a difference between scientific definitions of words and their common useage. This causes no end of anguish and confusion.
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Evolutionary scientists willingly agree that, yes, in terms of descent, we are all fish. The thing is, such a definition is too broad and all-encompasing to be useful.
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Truth be told, we humans have spent a disproportionate amount of time studying and classifying a small slice of the animal kingdom, namely the vertebrates. There are whole phyla that are fairly poorly known. It has been said more than once that if vertebrates had received as much attention from taxonomists as some other phyla have, then we would all be lumped together as “fish.”
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Cladistics seems to be leading taxonomists to abandoning such categories as Kingdom, Phlum, etc. etc. All life is related, descended from the same primaeval organism. Identifying reproductive species is relevant; other categories are losing their meaning. Or, to paraphrase Democritus, “All that exists are species and empty space; all else is opinion.”
And, as Steven Gould has often said, just because you can give something a name, doesn’t mean it exists. 
“The dawn of a new era is felt and not measured.” Walter Lord
DrFidulus. There are rules for this sort of thing, there is an international board fo scientists that decide the scientific grouping of living things. They say birds are in a different class than dinos. Thus by NO standards are Birds=dinos.
There may well be an arguement that birds should = dinos, but they “ain’t, period”. Not now in any case.
I’ll be sure to mention it (again) to the secretariat next time I am in London. These things take time. Remember, it took over seventy years to get the Brontosaurus/Apatosaurus contrempts cleared away. The members of the commission spend more time clearing up priority issues than re-evaluating the relations of higher taxons. Damnably conservative group, I think its because there are too manny French scientists represented.
More clarity is needed, i think.
Birds are included in the Dinosauria under the system of cladistics, the one most evolutionary scientists use. Cladistics only allows certain types of groupings: those which are monophyletic, meaning they include all the descendents of one common ancestor. Polyphyletic groupings, which contain the descendents of two or more common ancestors (like bats and birds) are not allowed; neither are paraphyletic groups, which include only some of the descendents of one ancestor. It’s paraphyletic groups which usually cause the trouble, because when we’re only dealing with animals alive at one point in history (like now) it seems most reasonable to group them by shared characteristics rather than shared descent.
To steal an example from the exhaustively quoted S. J. G., we look at a lungfish, a salmon, and a human, and we want to put the two fish together and the human separate, even though the lungfish has a more recent common ancestor with the human than with the salmon. We want to make a paraphyletic grouping of physically similar animals, fish, while excluding some of the descendents (us) of the ancestral proto-fish. It’s similar with dinosaurs and birds. If we exclude birds from dinosaurs, we have a paraphyletic grouping, since birds descended from dinosaurs.
Even though cladistics looks goofy in cross-section, as with the human/lungfish thing, it’s quite useful when dealing with histories, like dinosaurian evolution. Keep in mind that dinosaurs did not all look even remotely the same, or live at the same time, and that birds have many peculiarly dinosaurian traits, and it doesn’t seem quite so ludicrous.
Phantomwise
…never seen by waking eyes…