However they may have butted, they certainly didn't lower their heads and charge at each other the way deer do. The vertebrae of the neck wouldn't allow such a posture, and the rounded domes would cause their heads to slide off each other. It was almost certainly near-stationary butting, either head-to-head or head-to-flank.
Will in Seattle, stop ruining the dinosaur threads.
Sadly, the t-rex destroyed all of them.
Will in Seattle, stop ruining the dinosaur threads.