T-Rex/Spinosaurus comparison

I believe the sense of smell and intelligence thing is entirely hypothetical, right? If I am wrong, please provide evidence that not only describes the sinuses and brain cavities of tyrannosaurids (or just tyrannosaurus to be more specific) IN COMPARISON TO OTHER THEROPODS

Anyway, aside from that, I am not sure if I agree with all of this. For one, tyrannosaurids were likely NOT slow; sure they were particularly thick and robust in build, but I am pretty sure that their legs were in fact longer proportionally than most other large theropod genera (spinosaurus for sure), and even if that is incorrect, they were certainly VERY powerful. Spinosaurus was very likely the much slower animal here (and that does not even put its enlarged spinal column into account, which would have made its speed even more of a disadvantage)

Second, despite tyrannosaurus having a proportionally larger head than spinosaurus, I would not consider it "oversized". One thing that you forgot to mention is their actual weaponry differences and how they would correlate with the size of the animals. A uniqe factor for tyrannosaurus is that its bite force was undeniably very powerful, and its skull was largely heavily-constructed and designed for crushing; while its dentition was peculiar for theropods in that it was thickened in cross-section and much more dull along the edges than many other genera.

As for spinosaurus, it was far more unique: its snout was highly slenderized and was basically the polar-opposite of tyrannosaurus' snout in terms of shape and specialization (I'm sure you know this, but it would be wise to include it in your post). And as well, its dentition completely LACKED SERRATIONS overall and was almost perfectly circular in cross-section (it was a conical shape); it was not designed for slashing or ripping as all and was instead only really designed for deep/efficient puncturing and gripping, making not only its shape but also its specialization very much different.

Finally, you must consider size (spinosaurus was a lot larger; quite common knowledge for people who study this stuff) and diet (ceratopsians, hadrosaurs, and ankylosaurs vs large freshwater fish)

For the record, I DO have opinions on this subject, but I prefer to talk about it on a more scientific as opposed to opinionated level

If you'd look at the date this was posted (June 20, 2013), you would realize I was still fairly new to the forums at that point, and I was trying to not piss off some fanboys, so yeah, I see where you're coming from. 

Tyrannosaurids were some of the most advanced predatory dinosaurs to ever walk the earth; evolutionarily speaking. They evolved to become the apex predators of their environment; out competing the allosaurids(correct me if i'm wrong).

 Finally, you must consider size (spinosaurus was a lot larger; quite common knowledge for people who study this stuff) Not actually common knowledge, as the size is disputed almost every day! can you provide evidence of it being substantially largeR?

 I remember jack Horner stating Tyrannosaurus Rex had one of the best senses of smell of any animal...with the exception of the turkey vulture. He used that to complete his crazy Rex being a scavenger hypothesis. I myself believe it would scavenge, as all predator do at one point. But an animal 7 tons in weight can not efficiently feed itself on only carrion, In addition, we have evidence of tyrannosaurus predation.

I found an article linked to study stating that Tyrannosaurus did in fact, have the keenest sense of smell of the theropods. 

Here's an exerpt..

"The researchers looked at the importance of the sense of smell among various meat-eating dinosaurs, also called theropods, based on the size of their olfactory bulbs, the part of the brain associated with the sense of smell. Although the brains of dinosaurs are not preserved, the impressions they left on skull bones or the space they occupied in the skull reveals the size and shape of the different parts of the brain. Zelenitsky and Therrien CT-scanned and measured the skulls of a wide variety of theropod dinosaurs, including raptors and ostrich-like dinosaurs, as well as the primitive bird Archaeopteryx." You can find the article in its complete form below.

http://www.sciencedaily.com/releases/2008/10/081028205650.htm

Spinosuchus, in response to your "substantially larger" statement, here are the size ranges I've seen for both animals in my 15 years of studying prehistory...

Tyrannosaurus-

36-50 ft long

10-23 ft tall

4-12 tons

Spinosaurus-

33-60 ft long

10-26 ft tall

3-23 tons

So, no, the size difference is not common knowledge. There's a lot of overlap and times when T.rex is bigger and Spinosaurus is bigger. It varies to much to make a statement about which was bigger with any real certainty. Hope that makes sense(it came out a little differently than I hoped).

I have read a multitude of times with different sources that spinosaurus, basing it off of more complete spinosaurids, would yield a max size at around 55 feet in length (note that it seems as if spinosaurines were bulkier than baryonychines). A size of 50 feet is absolutely nonsensical for tyrannosaurus! And 23 tons for spinosaurus is even more ridiculous

"I remember jack Horner stating Tyrannosaurus Rex had one of the best senses of smell of any animal...with the exception of the turkey vulture. He used that to complete his crazy Rex being a scavenger hypothesis. I myself believe it would scavenge, as all predator do at one point. But an animal 7 tons in weight can not efficiently feed itself on only carrion, In addition, we have evidence of tyrannosaurus predation."

-Size is not determined by diet... A scavenger could just as likely survive off of carrion as a potentially even much larger animal (spinosaurus) could live off of fish solely (albeit largish fish. But this is a common argument for people on Topix and such; that spinosaurus "could not only live off of fish"). But the truth is, it was simple adapted to do so, and opportunist feeding (while definitely possible) is not a necessity for survival. The same thing can be said about tyrannosaurus, although I personally believe that it was primarily a predator that would have killed differently from most other similar theropod groups such as allosauria and megalosauria (that does not encompass spinosauridae)

I didn't say it did. Tyrannosaurus, and indeed every land based carnivore to ever live in the history of the earth can in, no way, sustain itself solely on carrion. Even the animals today we see as scavengers - hyenas and vultures - take living animals. That whole "rex is a scavenger" hypothesis has been debunked and discredited....you should know that one.

Nor has any predator fed on one particular prey species its entire life span. Oppurtunistic feeding is indeed a key component in predators. Even an animal specialized in feeding on fish - like the sea eagles - will take birds, sea snakes, mammals, etc. You cannot claim that Spinosaurus didn't partake in this, unless you have evidence to the contrary. I would say it is a necessity, as what would an animal as large as spinosaurus do if the rivers it was so adapted to dry up? the population would starve; the species would vanish into extinction rather quickly. There is little doubt it fed on other animals. you saying otherwise is pointless speculation!

 A size of 50 feet is absolutely nonsensical for tyrannosaurus! 

Can you point me to evidence that says Tyrannosaurus could not reach that length? I myself seeing 45 feet as a maxiumum, and a weight around 9 tons. But that's besides the point.

I'd like to add that of course Tyrannosaurids had a different killing technique then the other theropod families! it's dentition was meant for crushing bone a far distance from the slicing, gripping, tearing teeth of other theropod families.

I bet people thought Alamosaurus reaching over 100 ft long and 80+ tons was crazy too, but they found evidence for it. Saying an animal could not reach a certain size when that animal has been dead for millions of years is ridiculous. Personally, I put T.rex at 40-50 ft long and 8-14 tons(I can explain why if you want, but if you know anything about me, then you already know why) and Spinosaurus at 46-56 ft long and 5-8 tons(same as what I said about T.rex).

"Nor has any predator fed on one particular prey species its entire life span. Oppurtunistic feeding is indeed a key component in predators. Even an animal specialized in feeding on fish - like the sea eagles - will take birds, sea snakes, mammals, etc."

-I realize this.

"You cannot claim that Spinosaurus didn't partake in this, unless you have evidence to the contrary. I would say it is a necessity, as what would an animal as large as spinosaurus do if the rivers it was so adapted to dry up? the population would starve; the species would vanish into extinction rather quickly. There is little doubt it fed on other animals. you saying otherwise is pointless speculation!"

-Except I never claimed that... During a drought it woud nonetheless be a moment where opportunist feeding is likely for spinosaurus; I do not deny this. But the claim that it hunted dinosaurs for the most part is baseless, because we have evidence of the contrary

"I'd like to add that of course Tyrannosaurids had a different killing technique then the other theropod families! it's dentition was meant for crushing bone a far distance from the slicing, gripping, tearing teeth of other theropod families."

-I get this. This is one of my primary points in these arguments

 You bring up interesting points Spinosuchus. You see, the biggest reason (that I see) that we stick up for Spino some is for the specific purpose of avoiding problems caused by one or two individuals on these forums, though neither have been on for over a month. I will say, I agree with a chunk of what you say, just don't go saying that we have radical opinions (50 foot Rex, for example). 

ok, then i'm lost. What argument are you trying to make?

Just a fact, but in the book (not the movie) t. rex swims so you could say t. rex can swim.

But that is a book though... I am pretty sure it could have but that is just a science fiction book.

I'm pretty sure any dinosaur could swim, just some would be better than others.

What Mr. Happy said. I think if Spino swam, it would be an extreordinary swimmer.

Hmm...

How'd this get stickied...

Life is full of misteries Paden...

This one is the biggest of them all...

Beats me. Maybe it was one of the first comparisons of the two without the person looking like a fanboy or douchenugget. 

I've just been going through the Stickied topics...

You do have a Non Douchenugget thing going on with this one. 

I don't think spino was slow.

@ Jezza, we don't have its legs. We cannot really know how fast it was, but most of the multi ton theropods weren't very fast at all. There was no need to be. The prey they hunted was low and lumbering for the most part, with a very few exceptions.