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Re: Sauropods and Endothermy
REPLY: Thanks for the interesting note. "Willow", and
Dale Russell's justified excitement about this
fascinating specimen, fills a large file in my office.
However, I would like to point out that sauropods are
not ornithischians, the morphology of thescelosaurs
being significantly different from the multi-tonne
sauropods. Roger Seymour has done excellent work on
the cardiovascular systems likely possessed by
sauropods (his work over the past 20 years has not
been refuted), which I urge you to analyse. Also, it
should be noted, for historical accuracy, that L.S.
Russell in 1965 proposed endothermy (there were others
previously, but L.S.R. deserves much of the credit for
his formulations), a paper familiar to John Ostrom.
The other individual you mention, while being a fair
sketch artist, did not originate, nor add much to, the
variable meanings of endo- and ecto-thermy, although
barneyologists have embraced his hat (everytime I see
that hat, I want to stomp it with "Wipe Out" as
background elevator music!). Thermoregulation is far
more complex than some have thought: marine iguanas
are capable of foraging, e.g., in icy cold waters, yet
do not collapse dead. Sea turtles can migrate
thousands of miles, at a steady pace, yet do not die
on their way in similarly cold waters. What I am
saying, I guess, is that not all dinosaurs were
hot-blooded, but this does not mean, I hasten to add,
that they did not have high levels of activity.
--- Kashman7@aol.com wrote:
> Stefan Pickering writes 1/4/2003 under Alan
> Feduccia's medievalism in the
> February 2003 Discover:
> >>I do not believe sauropods were "pure" endotherms
> based on their probable
> cardiovascular requirements, but this does not mean
> they are not active
> I'm sure you read about "Willow?" The dinosaur with
> a heart?
> While not a sauropod Willow is at least an
> ornithopod and therefore a fellow
> Ornithischian. It is, of course, Saurischians that
> are supposed to be more
> closely related to avians.
> With Willow Dale Russell has discovered what is
> probably the only known
> fossilized heart of a dinosaur. The fossil in
> question was discovered in
> northwestern South Dakota in 1993 in northwestern
> South Dakota by amateur
> fossil hunter Michal Hammer. The official research
> paper on the specimen was
> published in the April 21, 2000 issue of the journal
> Science, about seven
> years after the initial discovery.
> The fossilized heart was discovered in the chest
> cavity of a skeleton of the
> dinosaur Thescelosaurus, a 660 pound, 13 foot long
> plant eater that lived
> within a million years of the time of the supposed
> total extinction of the
> non-avian dinosaurs 65 million years ago. Russell
> and his team are certain
> that the find is providing new clues into the
> ancestry of birds and the
> question of whether dinosaurs were warm or cold
> CT scan results reveal an internal structure
> consisting of a four chambered
> heart with a single aorta. This type of heart is
> very similar to that of
> birds, but far different from the three chambered
> hearts seen in today's
> reptiles. There is a built-in implication to the
> findings that at least some
> dinosaurs, like Thescelosaurus may have been warm
> blooded and capable of high
> metabolic activity, as long proposed by Robert
> Bakker and John Ostrom.
> See sites:
> and, from
> What are your feelings as to how this may make your
> statement re-thinkable?
> Or not, as the case may be.
> Lawrence S. Kashdan
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