Comment on Triceratops by DrScottHartman
So the mistake you are making is that you are letting the theoretical tail walk the empirical dog here - that is, you have created a reasonable sounding hypothesis, but are then trying to rationalize away data that doesn't agree with it. The bones suggest that Triceratops is simply not as fast as some of its smaller ceratopsian brethren, but it does appear to have great power available in the legs. We have to try and figure out why it was built that way.
Oh, I don't disagree with the evidence. I just wonder why.
Maybe T. rex wasn't as fast as earlier (and smaller) tyrannosaurs also, so power outweighed speed as a selective pressure? Or maybe there's actually a biological limit effect that forced the tradeoff. Or maybe intraspecies interactions were more important than predator/prey ones and that favored power over speed?
I did a little research, and I think I found a common link between frill size and horns and a potential explanation as to why Triceratops evolved this way. When comparing main predator of several ceratopsians (Styracosaurus, Chasmosasaurus, of course Triceratops) and their size, in respective order (Albertosaurus, Daspletosaurus, and Tyrannosaurus) one can see that the size of the frill for all but Triceratops acts as a shield for the sensitive nape of the ceratopsians neck. As a actual shield, in terms of functionality, it is weak but intimidating enough to prevent a predator to obliterate it with a charge. For Styracosaurus in particular, one can see the horns on top of it's frill are perfect for puncturing the neck of Albertosaurus in a situation where it goes for the back of the neck. The fact that these ceratopsians with large frills also have horizontal tails is interesting. Meaning it was unlikely they could use their hind legs to lift their upper torso off the ground.
I think Triceratops evolved considerable hind leg strength in order to rear up when fending of it's main predator, Tyrannosaurus Rex. When you look at Nasutoceratops, it's horns are formidable, but a Gorgosaurus could easily reach over and kill it with puncture of the jugular. The hind legs of Triceratops and Nasutoceratops are very similar, leading me to conclude they may of had similar strength as well as a similarly short tail. Since these two animals have similarly small frills and hanging tails, maybe they had small frills to reduce weight.
I think Triceratops evolved considerable hind leg strength in order to rear up when fending of it's main predator, Tyrannosaurus Rex. When you look at Nasutoceratops, it's horns are formidable, but a Gorgosaurus could easily reach over and kill it with puncture of the jugular. The hind legs of Triceratops and Nasutoceratops are very similar, leading me to conclude they may of had similar strength as well as a similarly short tail. Since these two animals have similarly small frills and hanging tails, maybe they had small frills to reduce weight.