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Re: various & sundry



Thomas R. Holtz, Jr. wrote:
> Actually, it is an Agro School department, a recent fusion of the old Dept.
> of Animal Science and the Dept. of Poultry Science.  Not much in the way of
> zoologists (exclusive of ornithologists) or ornithologists in either old
> department or the new one.  It is mostly nutritionists, animal husbandry
> researchers, etc.

Oh, ugh.  In that case, yeah, I can definitely see your point.
 
> Christian Kammerer's suggestion of using "reptilian" to refer to "a member
> of the clade Reptilia" isn't bad, but I'm afraid that the same arguments
> against the cultural baggage associated with "reptile" apply equally well to
> "reptilian".  Furthermore, the idea that we should exclude nonavian
> dinosaurs from "reptiles" (sensu Kammerer) because they were warm-blooded
> is, unfortunately, still premature.  Despite a quarter century of research
> by some very, very smart people, there is no consensus yet as to the thermal
> physiology of nonavian dinos.  In fact, Horner has gone as far to say (at
> recent conferences) that maybe they reason we haven't answered the question
> "Were dinosaurs warm- or cold-blooded?" is because that is the WRONG
> question!  (The question he, and most others, would prefer is "What sort of
> thermal physiology did dinosaurs have?").

This makes a lot of sense to me.  Given the way some "ectothermic"
animals generate heat (thinking pythons here and their nesting behavior,
but also some nifty tricks in fish) it seems to me that thinking of
thermal physiology as a binary question is fundamentally wrong-headed.  

> Many people working on dinosaur physiology suspect that there may have been
> more than one different types of thermal physiologies among the dinosaurs,
> and that only some of the dinosaurs had avian-style tachymetabolic
> homeothermic endothermy.

Given the variation in our clade reptilia, this seems quite reasonable
to me.  It's been suggested that sauropods might have generated heat
just by being so damn big, while most maniraptorans might have been
homeothermic just like birds.  Not an easy question, to say nothing of
answers.

> And, finally, to Norm King's assertion that "any child knows that turtles
> are reptiles".  This is wholly a case of education, and could (and can) be
> corrected by new education.  The idea of grouping non-warm-blooded scaly
> terrestrial egg-layers is not a "natural" one: no culture outside of Western
> science in the post-Linneaus era ever did this.  (At least none I have heard
> of).  

This is true, in my experience (actually fairly broad wrt other
cultures).  Other cultures don't get hung up on classification in the
same manner as we do, viewing animals individually instead of as
groups.  This of course has its advantages and disadvantages; using
"reptilia" in such cultures is much less problematic, since they have a
lot fewer preconceptions about what it means to be a reptile.

> The idea that turtles, lizards, snakes, and crocodiles form a group of some
> sort is not something that kids automatically know; it is something they are
> taught.  Teaching the paraphyletic sense had its purpose, but it is time to
> move on.  As Darwin suggested back in the 1850s evolutionary history and
> common ancestry should be the key concept in classification.  It has now
> reached that status within the science.  It is our duty and responsibility
> as scientists and science educators to help bring this concept to youngsters
> and other interested parties out there.

Yes.  I think that eliminating the use of "reptile" in the common
parlance might be a good way to go about this wrt our scaly (and
not-so-scaly) friends, particularly since there aren't any "100 level"
characteristics to pin on reptiles which would make it easy to teach
youngsters about them (and let's face it, we need stuff like that when
teaching kids; arguments about bones go right over their heads unless
they're really into this stuff).  Since we can't get rid of the term we
might as well try to get rid of the baggage that goes with it, and IMO
part of that would be eliminating it from common usage.
 
> Now to get a glass of wet water and get back to grading dino exams...

Ugh.  Have fun.  :-)