"New estimates of dinosaur body mass?" Topic

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I suppose this will allow paleontologists to recalculate how fast dinosaurs could move. Does 40% lighter mean 40% faster?

IIRC a mummified dinosaur was found some years ago and it was far more massive than previous reconstructions. So who's right ?

Also bear in mind, it's bad science in the article- they're basing their estimates and evidence on modern mammals, despite the fact that mammal, reptile, and avian muscle density, builds, skin, and so forth are not the same.

- Monk

Yes, that is bad science there.

"Also bear in mind, it's bad science in the article- they're basing their estimates and evidence on modern mammals, despite the fact that mammal, reptile, and avian muscle density, builds, skin, and so forth are not the same"

True, but I would think that many dinosaurs would be less massive than similarly sized mammals. Several known dinos had pneumatic bones:
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Lighter means considerably faster, but I doubt it is a linear progression.

Still, large beasts can be surprisingly quick, especially in short bursts.

hmm, lets see,

I estimate a 40% lighter dinosaur would travel at aproximately the same rate as a similar dinosaur would if it were 10% heavier.

I assume this as some of the body mass will be muscle, and some will be other structures. Just because an object is lighter, it is not always faster in nature.

So with smaller (weaker) muscles pulling a lighter frame at similar top speeds as before.

However this is just one scientists version, and I can remember a kerfuffle in the 80s over mandible muscle attachment and anchoring in large theropods, that had big cheeked dinosaurs becoming popular before they slimmed down again in the noughties. Without definitive proof (a mummified dinosaur (with some flesh and skin in a good state of preservation) I am assuming that this is the case of a curator or prof, with a pet theory to get publicity for a book out of it.

If you read the article, it appears that this new method of determining approximate weight of dinosaurs purports to be more accurate because it uses more accurate measurements than previous studies. It also assumes that using these measurements to determine dinos weight by comparison to other large non-extinct animals that have been measured the same way is valid. The article says 21% lighter. I'm not sure where 40% came from. It seems to me that there is not a direct link that can be made between weight alone and speed. The structures obviously factor in as the weight changes. However, greater accuracy in the calculations might mean a more accurate power to weight ratio.

For speed measurements they have found dino tracks which are a great yardstick for establishing how fast they went.

Yeah, weight doesn't have a direct correlation with speed, there are a lot of structures that aid in running.

Muscle mass is important, but so is the type of locomotion or limb lengths. A digitigrade is more likely to be faster than a plantigrade, regardless of weight.

A good example are humans. Females while slimer than males are not faster. Part of the reason is due to muscle mass, but the pelvis shape required for safe childbirth is at odds with the ideal locomotion pelvis.

Things like tails also merit consideration, etc.

Leg length is generally a better indicator of speed than weight. In fact I don't know of any formula that uses weight to calculate dinossaur speed (altough there probably are some).

And a 6 ton elephant is actually faster than a roadrunner if you ever wondered.