Do you think giganotosaurus could beat t.rex?(I think it could) For one thing, giganotosaurus was bigger,and had a much bigger skull. Even as we speak,larger-younger relatives of giganotosaurus keep turning up,in the southern hemisphere! The sharklike teeth alone are a pretty good size!(but I guess it doesn't matter that much, if you have bone crushing teeth,does it?) I know giganotosaurus did not have as big a brain as t.rex,or as solid construction,but I have reason to believe that giganotosaurus would ultimately win in a deathmatch. There's no doubt in my mind,that t.rex was pound for pound,a more effective predator, but i'm pretty sure giganotosaurus was capable of killing most of the same prey. (including horned dinosaurs,and definitely hadrosaurs) If you seen a giganotosaurus on display you'll know what i'm talking about! I'm dying to get this question answered!
from Sean.S, age 13, ?, ?, U.S.A; July 27, 2001

TOM: I've seen Giganotosaurus on display, and indeed it was pretty fearsome. Again, both it and T. rex were dangerous creatures, and either one could kill the other.

However, I must point out that Giganotosaurus' North American relatives (Acrocanthosaurus and its kin) did not survive long after the arrival of duckbills, horned dinosaurs, and primitive (small) tyrannosaurs. It may be that this body plan worked well in communities where sauropods were the dominant prey, but they were simply not smart or fast enough to cope with advanced herbivores (and possibly their smaller but smarter and faster competition). A lot more work needs to be done on dinosaurs of the earliest Late Cretaceous to figure this out for certain, though.