[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index][Subject Index][Author Index]

Re: [dinosaur] Running speed of Jurassic Park T. rex

Actually, I think that the variation of results is a feature, not a bug.

The reason for that is that there is an substantial number of things
we do not know:

- What is the exact mass of a trex?
- Where is its center of mass positioned?
- What is the weight-percentage of leg muscles relative to the total mass?
- How large are individual variations (I'm not as fast as Usain Bolt...)?
- What is the maximum force of a muscle per square centimeter (literaure values 
for measurements in living animals vary a lot, I've seen values between 150kPa 
and 400kPa, IIRC)?

All these strongly affect the calculated maximum speed. That's why
people like Hutchinson prefer to calculate ranges of quantities in
order to quantify our uncertainty. Nevertheless, the approach you
sketch has been pursued for example by Sellers.

In any case, considering that past estimates varied between 6km/h and
90km/h, I think the current agreement is that the top speed should be
somewhere between 25 and 45 km/h is not too bad.

Finally, although such numbers are somewhat interesting, from a
behavioural perspective I think that most animals only very seldomly
use their top speed.


PS: If you can read German, you can find a lot more on this on my blog:

Good day,

I have been reading an article about the famous "chase scene" in original
Jurassic Park. The film sequence was slowed down so that CGI-made
tyrannosaurus was not running at 45 - 50 kph (and so was able to keep up
with the jeep) but rather something like 20 kph. CGI makers did a great job
at reconstructing the mode of a giant theropods movement, anyway. I just
wanted to ask, would it be possible to throw all the specifications of a T.
rex gait into some similar software and find out how fast it probably could
go? I know there were some attempts, but the results obtained vary too much.
Thank you in advance, Tom

                   Priv.-Doz. Dr. Martin Bäker
                   Institut für Werkstoffe
                   Technische Universität Braunschweig
                   Langer Kamp 8
                   38106 Braunschweig
                   Tel.: 00-49-531-391-3065
                   Fax   00-49-531-391-3058
                   e-mail <martin.baeker@tu-bs.de>
https://urldefense.proofpoint.com/v2/url?u=http-3A__www.tu-2Dbraunschweig.de_ifw_institut_mitarbeiter_baeker&d=DwIDaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=1MKVxcR4vjZpz7IZn50mYQYR6wovwsedFAaIYMGuQhc&s=eZqnAbTv4axKer1U3bdh1pa20LG4O5tfO9AuoHAiims&e= https://urldefense.proofpoint.com/v2/url?u=http-3A__www.scienceblogs.de_hier-2Dwohnen-2Ddrachen&d=DwIDaQ&c=clK7kQUTWtAVEOVIgvi0NU5BOUHhpN0H8p7CSfnc_gI&r=Ry_mO4IFaUmGof_Yl9MyZgecRCKHn5g4z1CYJgFW9SI&m=1MKVxcR4vjZpz7IZn50mYQYR6wovwsedFAaIYMGuQhc&s=hUKfvXaiwoZtUtXSbgU27MtMzs9qCAz8yJ6Vo4cfCRk&e=