When we say fighting, there's different kinds of
fighting, like one is just carnivory, a wolf goes and attacks a deer,
the deer is gonna fight back, so that's not really fighting. I think when we say fighting we mean
more sort of conspecific fighting, you know that, geting into fights with members of your own species, and usually thats over territory mates and food and that kind of thing. We have a little bit of evidence of that
certainly that some of the big carnivorous dinosaurs, like
Tyrannosaurus Rex on occasion have been found with bite marks on their faces
that have healed from other Tyrannosaurus specimens.