Response to HP Hutchinson (was: Re: Horner on NBC Nightly News)

["Demetrios M. Vital" <vita0015@umn.edu>]

On 19 Jul 2001, John R Hutchinson wrote:
> I'm not sure where I supposedly speculated that.  I certainly did not
ever
> say that in a paper.  I'd like to say here that I'd rather not speculate
at
> all on the precise maximum speed of a tyrannosaur or any other extinct
> animal.  I can't say for sure whether an adult tyrannosaur could move a
> maximum of 5, 9, 15, or 25 mph, but I can rule out some of the faster
> speeds.  It's hard enough to get the maximum, or near-maximum, speed of
any
> living animal, as my collaborative work on elephant locomotion has shown
> me.  Assigning a number to a maximum speed for an extinct animal,
> especially one that has some very different anatomy from from any living
> bird, ungulate, or elephant, is too imprecise for me to attempt right
now,
> given current knowledge.  In my work on elephants I've seen how
> quantitative speed estimates that get cited in the literature can too
> easily be taken as fact, cited repeatedly, then eventually become data in
> someone's bivariate plot and least squares regression... of dubious value
> if the speeds themselves are erroneous.  I think we're better off right
now
> using quantitative approaches mainly to test for qualitative differences
in
> locomotor function in extinct dinosaurs.  And doing more work with living
> animals, so we can better understand the basic mechanisms that underlie
> maximum speed.

I wrote about the elephant comparison (note that I said they were similar
in that they had no aerial phase) because of what HP Matthew Carrano told
me in a personal correspondence.  Also, I asked a similar question of Chris
Brochu about a lack of an aerial phase at a lecture at the Science Museum
of Minnesota, and he mentioned the work you ("you" being HP John
Hutchinson) and HP Carrano did on T. rex locomotor mechanics.

I wrote about the 9 mph number because of DML emails from attendees of the
Armour Symposium who reported a presentation in which you gave that figure.
 The other numbers were calculations given to me by HP Carrano in later
correspondences.

Again, my sources for citing the lack of an aerial phase are (I think)
reputable, namely, HP Carrano and HP Brochu.

And my sources for the 9 mph figure are members of this DML, whose emails,
in which the figure is reported, should be in the archives.  I believed
those reports, and thus cited that number.  Are those reports wrong?  You
can find what I'm referring to here:
http://www.cmnh.org/fun/dinosaur-archive/2001May/msg00354.html
Check the secod paragraph down.  Or, I'll just cite it here:

HP Steve Brusatte wrote (linked to above):
"John HutchiNson (I'm a
journalist that can spell) opened the day with an intriguing talk on
dinosaur
locomotion.  Basically, he recounted his disproving of the hypothesis that
Tyrannosaurus could run at speeds of 20 miles an hour (which has been said
in
the literature numerous times).  Instead, he said that Tyrannosaurus likely

couldn't run at all (meaning there was no aerial phase to its gait), and
its
top speeds were likely in the 9 mph range."

Either way, I will not cite that report again.  I hope I have not conveyed
any misinformation, or said anything wrong. I respect and have learned from
your comments above concerning the difficulty in guaging top speed in
extant and extinct animals.  Thank you for correcting me!

Hoping everything is cool, Demetrios Vital