|University of Bristol|
A site with many trackways may not necessarily indicate herding or other social groupings, especially if the hiatus between deposition was particularly lengthy.
However, there is evidence that, for at least some of the time, brontosaurs travelled in herds. At Davenport Ranch, Texas "the limestone records the passage of two dozen brontosaurs in a compact mass, the very largest prints at the front periphery, the very smallest in the middle of the group. So brontosaur bulls or maybe senior cows must have guarded their young." (Bakker, 1986). This interpretation has been modified by Martin Lockley (1986), who inferred from this and other Colorado tracks that larger sauropods ranged in front of smaller members of the herd and "were probably walking in some type of staggered or spearhead formation" (Lockley et al.,1986).
"There is evidence of predation, of solitary hunters stalking their prey, and of opportunists and scavengers roaming in packs" (Thulborn, 1990).
Trackways can also indicate swimming, stampeding or even limping dinosaurs (Thulborn & Wade, 1984 in Thulborn, 1990).
Any inferences about dinosaur behaviour will always be limited. We can never know the real complexities of dinosaur behaviour. In the film Jurassic Park we saw Velociraptors attacking their prey simultaneously from several directions after hiding quietly in the bushes. Such particular behaviours would be very hard to find or interpret from the fossil track record. Furthermore if they wererepresented, it is likely that several, equally-plausible behavioural explanations could be suggested.
Bakker R. (1988) The Dinosaur Heresies. Penguin Books, London.
Lockley, M.G. (1986) A Guide to Dinosaur Tracksites of the Colorado Plateau and American Southwest.Geology Deaprtment, University of Colorado, Denver.
Lockley, M.G., Houck, K.J., Prince, N.K. (1986) North America's largest dinosaur trackway site: implications for Morrison paleoecology. Bulletin of the Geological Society of America Vol.97, pp.1163-76.
Thulborn, R.A. (1990) Dinosaur Traces. Chapman & Hall, London.
Thulborn, R.A., Wade, M. (1984) Dinosaur Trackways in the Winton Formation (mid-Cretaceous) of Queensland, Lethia.Vol.12, pp.413-517.
Stance and Posture