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