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Dinogeorge Digest #1

The dinosaur list moderator tells me I've been timed out again for sending too
much crap to the list, so here in one e-mail is what seems to be everything I
sent to the list in the past day or two that I don't recall having had come
back to me, latest to oldest. It's not too difficult to construct such a
"digest" document, so perhaps I'll do that instead of sending individual
replies to dinosaur list posts in the future. The trouble with limiting the
number of posts per member is that at the beginning of the day you have no
idea how many replies you'll be writing as the day progresses, so you can't
pace yourself. (The batteries in my crystal ball don't seem to be working.
Sorry.) In most cases, if you don't respond to a post at once but are forced
to wait a day, your post becomes stale. (But, of course, since most of my
posts are stale anyway, this is not an added burden for you recipients.) The
way to proceed, then, will be for me to reply first only to the original
poster and anyone copied, then gather the day's interesting replies into a
digest for the dinosaur list, much as I have done here.

Subj:   Re: Ornithopter
Date:   98-06-25 11:41:52 EDT
From:   Dinogeorge
To:     jrccea@bellsouth.net
CC:     kazmer@hotmail.com, Dinosaur@usc.edu

In a message dated 98-06-25 10:19:04 EDT, jrccea@bellsouth.net

<< Ed Spencer (son of the designer of the Spencer rifle developed in the
 1860's), designer of the Republic SeaBee and the Spencer Air Car, also
 designed and built many sucessful flapping ornithopers that flew quite
 well.  Ornithopters were not unsucessful, and were named to reflect that
 their flight mode imitated bird flight.  I find it amusing that we are
 now encouraging a double reflection of the derived term back to describe
 the original mechanism.  I'm not in favor of doing so.
                        Best wishes, >>

I was referring to a man-carrying ornithopter in my original reply; sorry
about not being specific enough. I used to have a rubber-band-powered working
toy ornithopter when I was a kid, so I know that man-made ornithopters can
fly. And--if you don't like the term "ornithoptering," you can always suggest
a better one.
Date:   98-06-25 11:32:05 EDT
From:   Dinogeorge
To:     SUTTON.JAMES@EPAMAIL.EPA.GOV, dinosaur@usc.edu

In a message dated 98-06-25 06:52:02 EDT,

<< It is and always has been, for them, a political issue just as the
 universe was in Galileo's time.  The question then and now is not "does
 the earth go around the sun?" or "did things evolve according to
 impersonal law and without a creator?" but "who shall have the
 Authority to say which way it is?" >>

I'm very glad to see that at least one other person on this list understands
the nature of the creationist problem. As I've said many times before, they
don't care about science, what they really want is >power<. The hard-core
ones, at any rate.
Subj:  Re: The Lake  Psittacosaurs
Date:   98-06-25 11:27:52 EDT
From:   Dinogeorge
To:     tlford@ix.netcom.com, dinosaur@usc.edu, Tetanurae

In a message dated 98-06-25 06:37:25 EDT, tlford@ix.netcom.com

<< They were sold by a dealer who reasured me that he got
 them legally, from a Museum in China (which shall remain nameless). I'm
 glad I got to see them. I asked the dealer if the owners would mind if
 they were desribed, and he said that that would not be possible, because
 of the 'owners' not wanting anyone to know they had them. Then why have
 them? >>

One of these specimens--the one with the splendid skull + premaxillary
fang(s?)--is I believe the best existing specimen of _Psittacosaurus
meileyingensis_. It's more complete than the type. Too bad,
Subj:  Re: Ornithopter
Date:   98-06-25 04:30:54 EDT
From:   Dinogeorge
To:     kazmer@hotmail.com, Dinosaur@usc.edu

In a message dated 98-06-25 03:06:23 EDT, kazmer@hotmail.com

<< I see the term Ornithopter has reared its ugly head again. 
 Those of us that have a strong interest in the history of 
 aviation are very familiar with Ornithopters.It is a 
 FAILED flying machine from the 1920's. It had an 
 airplanes' fuselage and a large series of whirling 
 circular banded blades that pumped up and down vigorously 
 while spinning and the whole result was the air (?) craft 
 hopped in place before falling into many pieces. How did 
 this term come to mean Flight of any kind? What was wrong 
 with flying or powered flight? Eschew obfuscation! >>

Ornithoptering is the kind of flying that extant birds do, as distinct from
the kind of flying that, say, flying squirrels or flying fish do. Just
because people couldn't build a working mechanical ornithopter doesn't mean
nature can't make a living ornithopter. The term "flight" is too general, and
I've had problems with people misinterpreting what I've written because I
haven't been specific enough about the kind of flight that
pre-_Archaeopteryx_ flying theropods might have been capable of. I am,
therefore, eschewing obfuscation by using the better-defined term
"ornithoptering" when describing "powered flight" or "flapping flight,"
neither of which is necessarily ornithoptering.
Subj:  Re:secondary flightlessness (wordy)
Date:   98-06-24 19:51:34 EDT
From:   Dinogeorge
To:     th81@umail.umd.edu, dinosaur@usc.edu
CC:     Dinogeorge

In a message dated 98-06-24 16:47:12 EDT, th81@umail.umd.edu

<< Under phylogenetic-driven hypotheses, all that would be required to
convince me that _Caudipteryx_, _Protarchaeopteryx_, _Mononykus_,
_Velociraptor_, _Allosaurus_, _Apatosaurus_, and/or _Triceratops_ were
secondarily flightless is to demonstrate that the most parsimonius phylogeny
places these taxa within a clade whose ancestral state is unambiguously
volant. This is the same standard which evolutionary biologists working on
other groups of organisms employ. >>

I, for one, don't think _Apatosaurus_ and _Triceratops_ were secondarily
flightless. (Sheesh!) They probably, however, had a common arboreal ancestor
with birds, way back in the Middle Triassic somewhere, when the first great
cladistic split occurred in Dinosauria.

Certainly life would be a lot simpler if it were always the case that we had
a phylogenetic bracket. But in the evolution of avian flight--as in the
evolution of avian endothermy, by the way--we do not. If we did, the case
would already be closed in favor of theropod secondary flightlessness, and
there would be no debate and no need for my attempts to convince anyone. (I
am, of course, eagerly awaiting the discovery of a small, 50-cm-long Early
Jurassic carnosaur with large forelimbs and feather impressions...)

We certainly know that avian flight evolved at >some< point in the evolution
of birds from theropods. The problem is, when? So far, we keep turning up
these Cretaceous birdlike theropods that can't fly, but since we know that
something like avian flight was already present in the Late Jurassic
_Archaeopteryx_, we know that a volant lifestyle was already being exploited
millions of years earlier. It seems most natural to me to conclude--or at
least to entertain the hypothesis!--that the flightless Cretaceous forms
descended from Jurassic fliers. This is because I believe that avian flight
took tens or scores of millions of years to evolve, slowly and
incrementally--allowing for the existence of thousands of potential flying
ancestral species--and because I think it is extraordinarily unlikely that
avian flight developed from the ground up, working on large, heavy animals
>against< gravity rather than on small, lightweight animals >with< it.

<<However, as Alan Brush & others were talking about in the post-press
conference milling about time, there are gradations in what we mean by
"fliers", and it may be that one or both of the new Chinese forms had the
ability to get off the ground for short pulses of airborn transport.
Whether we call this "flight" is debatable.>>

As I have noted in previous communications, I follow the dictionary
definition of flight, namely "passage through the air." The kind of flying
that birds do now, which is powered (by flapping) and unstable (for
maneuverability) and which I term "ornithoptering," is only one kind of
flight. There are also leaping, falling, parachuting, gliding, and powered
stable flight (perhaps we can call this "archaeoptering"), and possibly other
kinds of flight that we cannot visualize because there are no living animals
that exploit them. There are also gradations of flight within each of these
categories. "Flight" is a continuum that extends from falling to the kinds of
frenetic orrnithoptering that hummingbirds and swifts do.

Ornithoptering is so physiologically demanding and so contingent on the
possession of numerous specific anatomical features that it must have evolved
through lots of intermediate stages of less demanding kinds of flight: A
slightly better wing here, a slightly lighter foot there, somewhat stronger
pectoral muscles here, and so on. All cladists understand that the phylogeny
of theropods--as descendants of such intermediate flying forms--can provide a
roadmap to the evolution of avian flight. The problem is, I think, to
perceive the appearance of the various avian features (such as furcula, lost
manual digits, retroverted hallux, opisthopubic pelvis, stiffened tail,
hollow bones, bipedal stance, endothermy and/or aerobic metabolism,
maniraptoran forelimb, semilunate carpal, fused carpometacarpus, keeled
sternum, and so forth) among flightless theropod groups not as the
random-chance accumulation of characters but as incremental improvements in
the context of the evolution of avian flight.