Comments on: Tyrannosaurus Didn’t Have the Nerve to Run Fast

By: Kaleberg

Kaleberg — Fri, 16 Jul 2010 04:26:15 +0000

A shrew can run 16 mph. An elephant can run 25 mph. If we follow this series we would imagine a T rex could run even faster than an elephant, nerves or no nerves. Remember, walking can be handled semi-autonomously since it is a rhythmic action modulated by the elasticity of the muscles. Local neurons could control the muscles based on sensed tension, position and pressure.

Animals don’t have to use their brains for each and every step. Some animals can even walk after you disconnect their brains from their bodies by cutting their heads off. I agree that it is harder to make path corrections or respond to a varying surface if you have a long way from your feet to your brain, but a shrew probably has to do a lot of adjusting while an elephant can often just knock stuff aside. If nothing else, an elephant can see, and so plan, farther. A T rex could probably plan a path and pour on the speed.

I wouldn’t be surprised at all if a T rex could go faster than 25 mph, though I imagine one might take advantage of its slow brain time to escape. At 25 mph I doubt a T rex could turn on a dime.

By: ResearchBlogging.org News » Blog Archive » Editor’s selections: International romance, sluggish T-rex, double rainbows and World Cup excuses

Mon, 12 Jul 2010 16:09:18 +0000

[...] Tyrannosaurus didn’t have the nerve to run fast. Those scared to death by the t-rex in Jurassic Park can breathe a sigh of relief — recent research suggests that the “tyrant lizard” couldn’t move nearly as fast as depicted. Brian Switek of Dinosaur Tracking explains the reassuring details. [...]

By: Dinoluver

Dinoluver — Thu, 08 Jul 2010 12:27:55 +0000

Girraffes are generally light weight which would explain why they can run faster than an elephant.

But… an elephant is not as slow as you think, it can charge pretty fast and can turn on a dime. Rhino, same story, they are heavier than a girrafe, but can run even faster, they can also turn on a dime.

One other factor to consider is the oxygen levels of that time were (apparantly) much higher than today, which was one of the reasons they grew to such extreme heights. More oxygen means more energy, better blood circulation and may even have caused certain nerve systems to respond quicker.

So (in my opinion) the problem here is not the speed of the dino, it’s the size. The oxygen level had a direct effect on the animals growth rate. If dinosaurs lived today their mass would be halved, perhaps even more because the atmosphere simply can’t give them high levels they need to grow as fast.

That’s why they had such big plants, insects and millions of other animals that grew to such extreme heights.

Just something I heard a long time ago, and sorry for all the typo’s.

By: Mike

Mike — Thu, 08 Jul 2010 06:36:38 +0000

I’m not sure what should be so objectionable about the scene in JP. The T-Rex was chasing a jeep that was driving in the mud while in a heavy rain storm. I doubt the Jeep would have been going very fast. I certainly didn’t have the impression that it was when I saw the movie.

By: Jared

Jared — Wed, 07 Jul 2010 14:46:32 +0000

Giraffes, anyone? They can run upwards of 30 mph, and while I realize they use quite a different gait than T. rex or elephants, the nerves are still a bit longer.

Also, did T. rex and other theropods have a large pelvic ganglia?

By: jurassiraptor

jurassiraptor — Tue, 06 Jul 2010 23:47:47 +0000

If this study proves accurate, then wouldn’t that mean dinosaurs like Sauroposeidon, Amphicoelias, and their kin — the largest animals to have ever lived and many times larger than even T. rex — would have been essentially immobile?

By: Juan Ignacio Pérez

Juan Ignacio Pérez — Tue, 06 Jul 2010 18:08:26 +0000

Dear sir, just three points:
1) The post has not made clear which the journal that has published the original work is, CBP A or PRS b.
2) When you say “the extremes of the animal world”, I suppose that, actually, you mean “the extremes of the mammal world”, because it is obvious that there are smaller animals than a shrew, even among vertebrates.
3) The stimulus conduction speed was probably the same or similar but it should not be, because if fiber diameter is twice in the elephant, stimulus speed should be higher.