Oct. 19, 2006 — The mysterious moves of two-footed Jurassic dinosaurs traveling along a long-lost beach have been brought to life with emus.
Unlike computer models that have been developed to simulate the gait, and therefore the possible trackways of specific dinosaurs, live emus allow for direct comparisons of complex tracks to specific behaviors, say researchers looking at the thousands of tracks left behind 165 million years ago by dinosaurs at Red Gulch in northern Wyoming.
Among the surprises they’ve found is that tracks once interpreted as steady walking may actually be created by the animals stopping at mid-stride.
Another enigmatic type of trackway that now makes sense is where the dinos appear to have crossed one leg over the other. The motion is a seemingly weird thing to do, until you watch an emu making the same sort of track, explains Brent Breithaupt, director and curator of the University of Wyoming’s Geological Museum.
Emus, it turns out, have legs that are close together — like many dinos — and tend to look around a lot as they walk, Breithaupt explains. This scanning behavior causes emus to often cross the left foot over the right leg and the right foot over the left, making the same confusing pattern seen in the dinosaur trackways.
"Sure enough there are wonderful comparisons," said Breithaupt. "Emus are our biological Rosetta Stone."
He presents the latest on emus as proxies for dinosaurs on Oct. 25 at the annual meeting of the Geological Society of America in Philadelphia.
The search for a modern animal to act as a proxy for dino tracks started, says Breithaupt, because he was getting a little impatient with all the speculation about the trackways. There was too much of what he calls "prehistoric hyperbole."
