The Arms of T-Rex, are they Really that Useless?

Each arm of T.rex could lift some 450 pounds to be exact(900 pounds together).

I agree, the arms of Tyrannosaurus were likely used in some way and were not so useless. 

I have a feeling that T rex's arms shrank in order for the skull to enlarge. I also think it's possible that the reason the arms didn't disappear completely is because they stabilized the couple during mating.

For the male to have access to the female's cloaca, the female has to raise her tail, to near vertical. This puts her basically on all fours. She's not holding herself up, she just stabilizing herself wit her arms.

On the other end, the male now has 2 tons of tail to deal with, made easier by his arms being able to manipulate the female's tail.

I have also noted the narrowness of a T rex. Narrow snout, narrow chest, nearly no arms. Could this be for ease of movement in a forested environment?

Manipulation of prey just doesn't make sense to me, as a use for T rex's arms.

Perhaps they could be used in prey manipulation too....

Perhaps a T.rex would bite something, a hadrosaur perhaps, bring it close to it's own body, latch on with it's claws, and slash with it's back feet while balancing with it's tail. Or something like that.

See, I've always seen T rex as a hit and run hunter.

Attacking at high speed, arms held against the chest, jaws agape, the hit is accurate with the 3D vision and depth perception, the flexion of the skull and the massive essed neck absorbing the impact, the bone crushing teeth do their work and the rex comes away with a huge chunk of Edmontosaurus. The rex then breaks off, and allows the Eddie to limp away and bleed out, tracking the poor dying thing with its oversized olfactory organs.

Hitting the neck area behind the head, or the throat in a head-on attack on a bipedal, or say the upper thigh/hip area of a quadroped dinosaur would be the preferred area of impact, but by virtue of the ability of the teeth to penetrate and rend bone, even a "miss" could have the desired result.

It's all about enhancing the chance of success, whilst limiting the change of injury.

I could buy the arms being somewhat useful for corpse manipulation, but I just can't see such small, weak (900lbs between them is nothing when dealing with a gimballing, running hadrosaur) appendeges being useful controlling a 3 ton animal trying to get away as hard as it can.

Sadly, until we get a living T.rex, we will never really know.

We just need faster than light travel, and the ability to image the Earth's surface at a reasonable resolution from 65 million light years away! Easy peasy!

Oh, is that all? Haha

I like this a lot. Though the arms of acro were said to be abnormaly inflexible, not all carcharodontosaurids. I think carchydontosaurids(there has to be a easier way of saying that) had stronger arms then tyrranosaurids at parity because they used there arms a lot more. II say they used there arms more then tyrannisauruds.

It isn't neccessarily easier to spell it but you could say carchadonkadonks and we'd probably understand.

They probably had a use, Maybe on prey if it was very close and was already bitten, But we will probably never know for sure. 

This puts things into perspective. ^__^

I will say carchydons.

I also heard somewhere that they could lift up up to 500 pounds, and I've heard theories about them being used for getting off the ground, mating, holding prey, etc.

(If anything, were Carnotaurus arms useless? :T)

According to Andrea Cau, Carnotaurus' arms weren't even displayed:

http://translate.google.com/translate?u=http%3A//theropoda.blogspot.it/2013/07/le-braccia-degli-abelisauridi-erano.html&hl=en&langpair=it|en&tbb=1&ie=UTF-8

Ah, sparking an old debate. 

Casts of forelimb elements of the Cretaceous theropod dinosaur Acrocanthosaurus atokensis were manually manipulated to determine range of motion and infer function. It was found that the humerus can swing posteriorly into a horizontal position but can neither swing laterally to glenoid height nor anteriorly much beyond the glenoid. The forearm can approach but not achieve full extension and right-angle flexion. Pronation and supination are precluded by immobility of the radius relative to the ulna. Motion also seems to be restricted at the wrist. The palm faces medially, and digital movement is subtransverse. All three digits are capable of extreme hyper-extension. Digits I and II converge during flexion. Only digit III can be abducted or adducted. The limited anterior range of brachial motion infers that Acrocanthosaurus first apprehended prey orally, using the forelimb afterwards to secure its grip or deliver fatal blows. Acrocanthosaurus could only manually grasp prey that was beneath its chest, towards which it may have used its mouth to move prey. Struggling prey would have impaled itself further upon the permanently and strongly flexed first ungual. The range of motion in the forelimb of Acrocanthosaurus resembles that of Herrerasaurus and Dilophosaurus, and exceeds that of Tyrannosaurus. Acrocanthosaurus exhibits a greater manual range of motion than ornithomimid and deinonychosaurian coelurosaurs, but less at the shoulder and elbow. Coelurosaurian theropods exhibit reduced digital flexion and hyper-extension, which suggests a change in the use of the manus in coelurosaurs.

so it's almost certain that carnosaurs such as acrocanthosaurus used its for more powerful arms for more then tyrannosaurids such as tyrannosaurus.