Geoscience Reference
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counted a minimum of 130 animals; about 55% of these were theropods and 45%
ornithopods.
So instead of my recounting more of their evidence, I will let words from Drs.
Thulborn and Wade's first research paper about the site, published in 1979, speak
for the feelings these tracks evoked. In reading this, note how they broke an un-
spoken rule in paleontology, in that they expressed an emotional empathy with an-
imals from nearly a hundred million years ago:
Persuasive circumstantial evidence leads us to conclude that they repres-
ent a stampede—that is, a wild, unreasoning and panic-stricken rush to
escape the threat of danger. What could have caused such presumed pan-
ic?
Itwasagreatquestion,andintheirattempttoansweritThulbornandWadepointed
to the large three-toed tracks that entered the scene from the left. These tracks ori-
ginated from the same direction taken by more than a hundred small dinosaurs,
someofwhichranaroundandontothetracksofthebigdinosaur,interpretedbythe
paleontologistsasthoseofabigtheropod.Howbig?Asmentionedbefore,dinosaur
sizes can be estimated by their tracks: just multiply the length of the footprint by
4.0, and you have the approximate hip height of the dinosaur. In this instance, the
best-preserved track was 64 centimeters (25 inches) long, so its hip was about 2.5
meters (8.3 feet) off the ground. Just to put this in perspective, this is higher than
the tallest basketball player in the NBA, and would have been big enough to make
you and me run, too. So imagine the fright felt by a much smaller ornithopod or
theropod from the approach of such an imposing predator.
Compounding this effect would have been the contagious fear spreading in-
stantly through a sizeable group of small dinosaurs, instigating a chain reaction of
similar behaviors. Think of the arrival of a fox in a chicken yard, or even a human
walking up to a group of shorebirds, and how the jittery reaction of one bird is
enough to spook the others, thus causing all to share the terror.
