Re: New work on running biomech by Hutchinson

[Amtoine Grant <ajgrant@eastlink.ca>]

On Thursday, September 9, 2004, at 10:56  AM, David Marjanovic wrote:

> > Based on these models, the adult T. rex would not make a good
> > "fast runner" (fast running is defined in these papers as a Froude 
> > number
> > of ~17, which scaled to MOR 55 would mean 20 m/s).
>
> Which in turn, when multiplied with 3.6, turns out to be 72 km/h. 
> So... if
> it doesn't catch the jeep in JP I, it isn't running _fast_ yet. :o)

I'm not keen on exactly what a Froude or MOR number is, so basically 
what I'd like to know is why would it be multiplied by 3.6 for the 
adult Tyrannosaur?

> > All the other specimens seem to have been
> > fairly good fast runners. Hutchinson still regards a speed of >11 m/s 
> > in
> the
> > full grown T. rex as rather unlikley, but between 5-11 m/s not out of 
> > the
> > realm of possibility but requiring further study. At Froude = 17, the
> > Coelophysis would be moving at 8-9 m/s, and the small tyrannosaur at 
> > 11-14
> > m/s (the current upper ranges of footprint-based speeds).
>
> m/s   km/h
>  5     18
>  8     28.8
>  9     32.4
> 11     39.6
> 14     50.4
>
> Beware of small tyrannosaurs then.

Shoot, beware of Coelophysids!