Geoscience Reference
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thus provoking much head-shaking and sighing amongst other paleontologists and
dinosaur-track enthusiasts who wondered how this would end.
One potential source of error related by Thulborn was that the 1988 study on
dinosaur tracks done by the Spanish paleontologists was performed on a mixture
of only sixty-six ornithopod and theropod tracks, and only from one formation in
Spain. In other words, it was likely never intended as a universally applicable, one-
size-fits-all method that could be used on dinosaur tracks of varying geologic ages
anywhere else in the world. A second possible flaw is that the tracksite, once un-
covered in the 1970s, had been outdoors for several decades before having the pro-
tection of a building around it. (A roof covered the tracksite for a while, but this
shady spot in the middle of the desert attracted kangaroos, which found it a most
excellent spot to sleep and defecate. Trust me, this is not good for dinosaur tracks.)
Theirexposuremeantthatthetrackswereweatheredandhencealteredsincetheori-
ginal measurements were taken on them, decreasing the accuracy of any new num-
bers derived from them.
A third problem was that some of the “new” measurements must have been
taken from Thulborn's original line drawings rather than directly from the tracks.
This sort of extrapolation again results in diminished accuracy. A fourth prob-
lem—and in my mind, this is the biggest one—is that the foot structure of
Mut-
taburrasaurus
, the alternative trackmaker, is based on just five bones: three meta-
tarsals(heelbones)andtwophalanges(toebones).Yes,that'sright:Wedon'tknow
the actual size of its foot or other details of its anatomy. It would be like saying a
suspect in a crime was identified by his tracks, but the suspect only has two toes
on one foot and lost the other foot in an unfortunate accident. A fifth (but not final)
problem was an oversight, which was that a set of perfectly fine but smaller orni-
thopod tracks was only a few meters away at the same tracksite (remember the first
actorfromthestageplay?).Yetthesewereneitherstudiednorcomparedtothelarge
tracks to see whether they matched in their dimensions. In short, the re-study had
