Tyrannosaurus rex versus Spinosaurus aegyptiacus

[theropod]

You should probably take a closer look at their respective traits without making a guess solely based on prey.

However it is probably Spinosaurus that one could compare to a grizzly. Holtz once described it as a giant mixture of a bear, a heron and a crocodile, all on a theropod frame.

[grizzly]

I see and understand your point. Both have a few grizzly bear traits. But, these guys both kill with their jaws. T-rex has the more powerful set of jaws. Bone-crushing serrated teeth of a predator perhaps similar in some respects as a hyena. The teeth of Spinosaurus, as I understand, are designed for snagging fish. Am I wrong?

[theropod]

I would assume an animal like Spinosaurus wouldn't necessarily rely on its jaws to kill twice smaller opponents that would die or badly injure themselves in a simple fall...

This applies to fights between theropods in general. If Spinosaurus fought an animal the size of Carcharodontosaurus or smaller, I doubt if it got a hold on it it would have any problems toppling it over. Carcharodontosaurus in this scenario might have decent chances. But due to size deficiency, I don't think I would favour any other theropod discovered thus far, including the four other giants Spinosaurus coexisted with.

[Deleted]

Due to the huge dorsal spine of Spinosaurus to add to it's already impressive visual size, the Tyrannosaurus would be intimidated and would turn tail and rather flee. The fight could have been ended without a single drop of blood shed.

But if the Tyrannosaurus decides to attack anyway, Spinosaurus would win due to sheer size and strength.

[Vodmeister]

First impression would make me back the T-Rex, the Spino doesn't look particularly powerful build, and appears to have rather weak jaws and a fragile skull, whereas the Rex seems to have a much more powerful build and robust physique.

However, when you look at the size of the animal, then it becomes a whole other ballgame. The Spinosaurus is 23 tonnes compared to only 7 tonnes for the Tyrannosaurus, that shifts whole odds in favor of the Spino, who is the much larger and likely stronger dinosaur.

I have to back the Spinosaurus here, based on size, weight, and power alone.

[Grey]

Even if Spinosaurus did not reach the 23 tons mark but rather the 15 tons mark, still within the proposed range, it would have a definitive advantage over T. rex.

Which does not mean immune to attack, if T. rex managed to get the neck.

But overall I give it way more likely to Spinosaurus. However, at the body mass range proposed by Dal Sasso, T. rex capacities greatly increase.

It is speculative to say that T. rex would be really dissuaded by the sail of Spinosaurus. Some herbivores in its environments were not less intimidating.

I'd like to know about Currie's opinion hinted at the first page of the thread.

[creature386]

Jun 3, 2013 9:47:50 GMT 5 @brolyeuphyfusion said:

Due to the huge dorsal spine of Spinosaurus to add to it's already impressive visual size, the Tyrannosaurus would be intimidated and would turn tail and rather flee. The fight could have been ended without a single drop of blood shed.

If we count that as a victory, most carnivore vs herbivore matches would be mismatches.

[Deleted]

Jun 3, 2013 19:38:17 GMT 5 Grey said:

Some herbivores in its environments were not less intimidating

Alamosaurus was the only known animal in Tyrannosaurus' environment that was visually larger than Spinosaurus aegyptiacus. All the known others were similar or smaller in visual size compared to Tyrannosaurus.

[Grey]

Some individuals/species of Triceratops were heavier and bulkier than T. rex itself, some hadrosaurids were huge too.
Alamosaurus is a contender for the largest land animal known by reasonnable remains.

Tyrannosaurus was used to see big things and big opponents. And in all the cases, the visual impact argument is speculative, at best limited. Tyrannosaurus was no freakin' chicken.

There others arguments favoring the larger Spinosaurus, but not this one.

[creature386]

Jun 3, 2013 21:36:39 GMT 5 Grey said:

Some individuals/species of Triceratops were heavier and bulkier than T. rex itself

He talked about dimensional size.

[theropod]

Most of T. rex prey was pretty much its own size or smaller. I think at least when hunting very large Triceratops individuals, it would have done so cooperatively, to reduce the rist and increase the chances of success. Magnapaulia laticaudus (shouldn't it be laticauda?) was downsized to 12,5m, and edmontosaurus was 13m. These two would have been pretty much the same size or a bit larger than T. rex, but of course they lack the powerful defenses some smaller prey items had.
Ankylosaurus and the average Trike were both probably smaller than T. rex, tough formidable. That fits the fact that most predators prefer smaller prey, even if they quite often hunt large animals.

[Runic]

Jun 4, 2013 17:07:23 GMT 5 theropod said:

Most of T. rex prey was pretty much its own size or smaller. I think at least when hunting very large Triceratops individuals, it would have done so cooperatively, to reduce the rist and increase the chances of success. Magnapaulia laticaudus (shouldn't it be laticauda?) was downsized to 12,5m, and edmontosaurus was 13m. These two would have been pretty much the same size or a bit larger than T. rex, but of course they lack the powerful defenses some smaller prey items had.
Ankylosaurus and the average Trike were both probably smaller than T. rex, tough formidable. That fits the fact that most predators prefer smaller prey, even if they quite often hunt large animals.

I don't think that's always the case. Some smaller animal could have ways of defending themselves far more adequately than much larger prey animal. It's not the size that directs what predators hunt. It's the difficulty of killing it.

[theropod]

What's not always the case?

[creature386]

It seems like he means your last sentence.

[theropod]

Of course some smaller prey items can be more formidable in exchange, that was not what I meant. I meant like most predators the main component in T. rex' diet were probably specimens smaller than itself, not record-sized 9t ceratopsians or the very largest hadrosaurs.