any evidence that T-rex may have hopped like a kangaroo?

Watching the nature channel I couldn't help notice the similarity between the body of a t-rex and a kangaroo. I suppose the bone structure of a hopping dinosaur would be obvious to a paleontologist, and they know for certain that t-rex and his smaller relatives did not hop?

^^ ? They both have strong leg tendons but for different reasons. A kangaroo needs to travel large distances and hopping is the most energy efficient way. A T-Rex needs to transport a massive body around and hopping would not be the solution. Have you ever seen an elephant jumping around?

Yes they know for certain that T-Rex did not hop.

Have you ever seen an elephant walk on two legs (except in a circus)?

The highest gait that an elephant is capable of is an 'amble'

False analogy. While I do not see the similarity between T. rex and kangaroos very much, I know for a *fact* that there are almost *no* similarities between the leg structure of T. rex and that of elephants. As I've mentioned here before (in a thread about the 'T. rex as scavenger' theory a while back that focused for a time on running speeds), elephants are *very* atypical of large animals throughout biological history, because there are no non-human predators large enough to threaten them, so they don't *need* to be able to run or jump or anything like that, and natural selection has thus given them very weak, pillar-like legs. While I doubt that T. rexes hopped much, I am absolutely certain that they *did* do many things with their legs that elephants would be totally incapable of.

Which backs up the point I'm trying to make.

I am willing to stake my internet connection that T-Rex did not hop.

But they both have strong tendons which, are, or would have been very visible.

Large animals will not hop.

Will I agree with you T. rex did not hop, I do not believe there is one whit of evidence to back up this sort of overgeneralisation. The details of the musculature and body-mass distribution of an animal are *far* more important than absolute size.

It is entirely possible to imagine a real, viable animal that is 'large' (however you define that

I disagree. The more massive the body the more it has to deal with gravity. Evolution is continuously aware of gravity. I am not one for any generalisation but I think that in this specific case evolution could not get across the bridge.

The construction of a hopping brachiosaur is beyond nature and the human mind.

The physics of biological animals provides all the data in this instance.

I am only thinking of one specific example.

Do a stress analysis. I think the answer will be obvious then.

It seems like hopping might actually be more practical than running for a big animal.

Probably the difficulty for a big animal is that footprint and joint strength are proportional to cross section while mass is like volume.

On the other hand that tendon on a kangaroo can probably store energy proportionate to volume. So it's easier for a giant kangaroo to hop than for a giant ostrich to run. Also kangaroos hit with both feet.

It's exceedingly hard to link footprints directly to a fossil species known by skeletal remains and say 'these prints were made by this animal'. In fact, except in a very few exceptional cases (where both lots of skeletons and lots of footprints are known from the same part of the same formation from the same time and the skeletons clearly fit the footprints), there is no such thing as a dinosaur footprint that can be definitively assigned to one of the species known from skeletons, like _Tyrannosaurus rex_.

There are a lot of clearly theropodian footprints, and as far as I know none of them show evidence of hopping, but then again, we would not expect to see such evidence unless *most* theropods hopped. If just one or just a few species did, the chances of us finding their footprints are virtually zero

lololololololololololololololololololololololololololol oloololololololololo

no way! it walked and ran! it needed its big tale to balence it wall running! why would it waste that and hopp!

Don't think the T. Rex would've been capable of hopping more than 2 inches, if that..

Random Scientist Inc.

Maybe they hopped when they danced, or as in competition, hopped over things. Remember, trees were bigger then also, gravity was less at that time, and soforth. It depends on what sort of tennis shoe they wore too.

How was gravity less? I think it's been the same since Earth took its final shape (which it has today) at the end of the Pre-Cambrian Eon.

How was gravity less? I think it's been the same since Earth took its final shape (which it has today) at the end of the Pre-Cambrian Eon.

PS Tennis shoe....lol!

Random Scientist Inc.

Oh, dang it! It did the post twice again! LOL!!!

Random Scientist Inc.

Look at the skeletons of ALL of the large theropods and the Coelurosaurs like the Tyrannosauridae and get back to me. These animals were not built to "hop" like a kangaroo!

Why are we even comparing theropod dinosaurs to the mammalian Kangaroo?! They're not even remotely related. Try comparing avian theropods to birds and you'll get a lot farther.

Trust me, for a FACT, T. rex did NOT hop!!


As for the comment on less gravity in the Mesozoic, there is NO proof of that!! There is MORE proof of shifting continents than an expanding earth!!

How else could an animal grow so big unless it had super strength and ate Krypton, or if gravity had less pull. with the second option they would need only enough strength to hunt, eat, or protect themselves. There could be many factors, but this is my best guess for a 6 ton animal. Nothing alive except probably a tree root would probably know for sure, since it's known that the tree is the only thing that could live forever. There is also the earth that could really be a living thing. It keeps trying to control it's children, who don't always listen because they are always young. That is us and I am the same way, but at least I know it.

Science is, and will always be a logical "GUESS". I don't know how it changed to being fact. You take a guess, try to get evidence to prove it, and then you get a guess with proof that it is possible. That in essence makes it a logical guess, not a fact. I took science in school till it came out of my ears, and this is what they stressed, theory... So my guess that dinosaurs were competitive comes from watching all forms of nature.. Making science fun along with learning is a great thing. Being of a fairly high inteligence, I have learned that from even the dumbest thing or person, you always learn something if you look with an open mind.

I am amased about the amount of people that "know for sure" about something that that lived over 60 million years ago. a few centuries ago people "knew for sure" that the eart is flat! They also "knew for sure" That people with high fever are in danger of getting invaded by demons and that the heavenly bodies were pushed around by angles.

Looking at the bone structures of the kangaru and the T-Rex side by side, the similarities are quite aparent and 60 million years of evolution could easily have come up with the same solutions to transporting the body more than once just in different sizes. A simple thing like the eye has been invented several times in a similar manner.
There are no apparent reason why the bonestructure of the T-rex should not support hopping linke a kangaru! In fact that very point could solve the pussle about what they used their small arms for or indeed why they were so small.

Almost a year and a half ago dggkjgkfjsfg wrote what I consider the best response to this subject:

There are a lot of clearly theropodian footprints, and as far as I know none of them show evidence of hopping, but then again, we would not expect to see such evidence unless *most* theropods hopped. If just one or just a few species did, the chances of us finding their footprints are virtually zero

We can add to this that fossilized footprints are left in wet terrain and a hopping species might have walked differently on slippery grounds.

Back in early December 2009 a paper on computer simulations of dinosaur locomotion was released through Palaeontologia Electronica.
(link to the abstract)
The data actually suggested that kangaroo-like hopping would have been the fastest and most energy efficient gait for hadrosaurs. But the authors are not convinced that animals with stiff tails and a weight reaching 3-4 metric tons could in fact jump around. They blame the results on insufficiencies in the computer model. Quote:

Such a hopping gait is considered unlikely for this animal, which would imply that either our anatomical and physiological reconstruction is incorrect or there are important constraints such as skeletal loading and safety factor that are currently not included in our simulation.

According to their calculations, hopping or galloping would also place so much force on the hadrosaur's bones, that they would be in danger of breaking.

I imagine that hadrosaur hatchlings might have hopped around in addition to bipedal and quadropedal walking. If so, they probably abandoned it as they grew older and heavier.

Nice joke..
There is no way T-rex could hop. If it Hops,it will fall down and gets hurt for sure.

There is one way it could have hopped. If the humidity in the air would have been extreme as it may in the far future with global warming gone to extremes, and formed a sort of mineral plasma type air, then the density of the air could possibly make it possible for a 10,000 lb creature to have a actual weight of 5,000 lbs or less. It's like when we go swimming we actually weigh less than the water and float. Although their weight was still the same, the air subtracted some of the effects of gravity on the creature. The creature could grow to tremendous size in this case. It would have to have tremendous strength just to move through the air as we need to swim. All plantlife would also get to tremendous size. Bird like creatures could also fly without the aid of feathers as we know them, just peculiar shaped skinfolds or something. This theory is possible, but I do not know if it was really the case. I can only hypothesize (spelling?)

Rickymouse, humidity has nothing to do with it. Do you see the people in states like Florida or Georgia floating? No. We don't float in water because we weigh less (even though we do). It's because our density is less than the density of the water.

Random Scientist Inc.

I never said just humidity Random Scientist.

Alright, I apologize for the misunderstanding.

Random Scientist Inc.

Hello fellow carbon life forms. Just found this forum...Have always thought the T-Rex was just a huge carnivorous Wallaby...And I would like to know...was anyone there when the giant T-Rex roamed the earth??? LOL. So How do we really know what he looked like, or if he/she waked, ran, or jumped...And Do we really think the T-Rex was a reptile?? The scientist told the artist how to draw the T-Rex...now make sure you draw the t-Rex as a reptile or you are so fired!! The She T-Rex would look so cute with a Joey pouch, long ears (the better to hear with) and fur. Oh My...are we talking mammal here, much less marsupial?? And what doe the classification Macro pods mean?? Large foot..Contemplate. We live in 2010 not the ancient past. We do the best we can we science, deduction, reasoning....so why do the bones of the T-Rex look like a Wallaby?