Pachycephalosaurusfan

Psycopathy was probably useful in hunting, fighting and other dangerous activites, as they showed very little fear (often). Correct me if im wrong.

Tyrannosaurus was a large, relatively fast and (probably) highly intelligent hunter. That makes sense in terms of an ambush, but not really in the wetlands. It would be a waste of its attributes. It probably could swim, and quite well at that. But it was more suited for ambush tactics.