Subject:
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Re: Evidence of Warm Blooded Dinosaurs
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Newsgroups:
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lugnet.off-topic.fun
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Date:
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Tue, 25 Apr 2000 14:48:40 GMT
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Viewed:
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1100 times
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In lugnet.off-topic.fun, Lindsay Frederick Braun writes:
>
>
> Jeff Stembel wrote:
>
> > In lugnet.off-topic.fun, Bruce Schlickbernd writes:
> > > In lugnet.off-topic.fun, Lindsay Frederick Braun writes:
> > > > Jeff Stembel wrote:
> > > >
> > > > > Anyone interested in Dinosaurs should check this out:
> > > > > <http://www.washingtonpost.com/wp-dyn/articles/A53547-2000Apr20.html>
> > > > > Pretty cool, huh? :)
> > > >
> > > > I saw that! It sort of confirms what palaeontologists have thought since
> > > > about 1980. The fact that it's a plant-eater is more interesting,
> > > > though--the suggestion existed that "only predators needed that level of
> > > > energy." Hm.
> > >
> > >
> > > A similiar article appeared in the L.A. Times. One would suspect that
> > > warm-bloodedness goes back at least till the dinosaur-mammal split given • the
> > > plant-eater angle.
> >
> > This prompted me to pull out one of my dinosaur books, and examine the • dinosaur
> > family tree. :) Anyway, if this chart is correct (it's ten years old, but • I
> > doubt its changed much), then I'd guess Dinosaurs and mammals both evolved
> > warm-bloodedness separetly.
>
> Darn sacci-frasso-rassin' kids, stealin' my thunder...;) But yeah, that's the
> story. Why do crocodiles not have a high, warm-blooded metabolism? They • don't
> need it, and have never needed it. They're archosaurs like monotremes are
> mammals--they have *some* of the features, but not all. Dr Gregory Paul has
> written (and illustrated--he's quite talented) an excellent book called • "Predatory
> Dinosaurs of the World", in which he argues quite reasonably two things:
>
> 1. Dromaeosaurs and Cretaceous coelurosaurs (an outdated term, as it • conflates
> several distinct lineages) in fact are *back-evolved* from the first birds, • based
> upon structural information, metabolic clues, and evidence of later (post K-T) • bird
> back-evolution into large ground predators; and
>
> 2. Amateur and professional fossil-hunters both are guilty of mucking up the
> Archosaurian family tree by vainly trying to name "their own" dinosaur, and • thus
> giving specimens we can today quite readily tell are male, female, or • juvenile,
> three different genera names. Paul clears a lot of this up, and apparently he • made
> some people not-too-happy by suggesting that "their" dinosaur be collapsed • into
> another category.
>
> There's a corollary to this, and that's that birds should not be in a separate
> taxonomic class (Aves). Rather, they should be a subclass under Archosauria • (which
> should be a class, not a subclass of Reptilia as it's accepted
> now--Archosauromorpha). To call birds non-archosaurs is like calling bats
> non-mammals, just because they can fly.
>
> I'm not sure you can call late therapsids truly "reptiles," though. They were
> furry, after all. If you're talking finbacks (pelycosaurs/edaphosaurs), well, • yes.
>
> > I'd like to hear other's opinions on this, especially if you have evidence • to
> > contradict or confirm my idea (since I just made it up :) ). I'll also try • to
> > find some of my more recent books on the subject. :)
>
> I'm in basic agreement--although the relation of dinosaurian groups is kind of
> weird right now, because I've been seeing a lot of material lately that • suggests
> the "traditional view" separating dinosaurs by hip type is just plain silly, • and
> that separating them by size is also just plain silly. At least we know where • our
> 'gators stand; their ancestor arose in the mid-Triassic, about the same time • as the
> earliest known "dinosaur" (is that still considered to be Euparkeria, or do • they
> have a new "earliest and greatest" candidate?).
>
> best
>
> Lindsay
Fwooosh. Clearly I haven't been paying too much attention to the
taxonomic connections of the various dinosaur branches (here's a brachiopod,
memorize it, here's a spirifer, here another boring bi-valve, you'll find oil
near this one, etc. - never let geologists run a paleontology course <g>).
Bruce
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Message is in Reply To:
 | | Re: Evidence of Warm Blooded Dinosaurs
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| (...) Darn sacci-frasso-rassin' kids, stealin' my thunder...;) But yeah, that's the story. Why do crocodiles not have a high, warm-blooded metabolism? They don't need it, and have never needed it. They're archosaurs like monotremes are (...) (26 years ago, 25-Apr-00, to lugnet.off-topic.fun)
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