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(Fwd) Re: ELEPHANTS CANNOT EXCEED ~12 MPH!



Forwarded message:
From:     Self <mteuton>
To: GSP1954@aol.com,GSP1954@aol.com
Subject: Re: ELEPHANTS CANNOT EXCEED ~12 MPH!
Reply-to: tons@mail.netside.com
Date: Sun, 28 Sep 1997 01:12:39 -0500

> Date:          Sun, 28 Sep 1997 00:06:30 -0400 (EDT)
> Reply-to:      GSP1954@aol.com
> From:          GSP1954@aol.com
> To:            dinosaur@usc.edu
> Subject:       ELEPHANTS CANNOT EXCEED ~12 MPH!

> I KNEW someone would attempt to continue to argue that elephants can move at
> high rates of speed, and Chris & Michael did so. It cannot be overemphasized
> that this is simply not true.

Ok, so we disagree.  This is no reason to get upset or scream.  I am 
not threatened by the fact you think they cannot go faster than 12 
mph.
> 
> For a multi-tonne animal to move at 20-25 mph it would have to be
> galloping!!!! This is predicted by scaling of the trot-gallop transition, and
> by the example of rhinos which gallop at these speeds. Have timed them from
> videos. The laws of physics and animal biomechanics prevent a giant animal
> from walking faster than about 12 mph. The stride frequency would have to be
> impossibly high, twice what is attainable.  The very fast elephant in the
> race I timed was at its maximum possible stride frequency, so it obviously
> WAS going at its fastest speed. No one has ever documented an elephant moving
> faster than ~12 mph by a rigorous means. In science that means that higher
> speed claims are unverified until proven.

Whose rule is that and I will have to look at the original work on 
elephant locomotion.  This is getting deeper than just a yahoo 
search.  See my recent post about how elephants lift their hips to 
accelerate their limbs twice as fast as a pendulum would allow.  If 
this is true then interesting isn't it, how nature seems to get 
around things.    
> 
> So those who wish to claim that elephants can move faster need to prove it is
> so. Until then I suggest they sit down and work out the stride frequency
> required, and see if they can explain out how an elephant can walk as fast as
> a rhino gallops in a charge! 

This is an example of how we can get stuck in a rut and refuse to see 
the obvious or allow ourselves to process information.  Of course, 
I'm guiltly of the same thing at times.  Also, a rhino is faster than 
an elephant.  They can gallop which is amazing in itself.  Why must I 
prove it so?  I am comfortable with my knowledge and have gained from 
yours.  
> 
> The citation of bee flight as an example of how animal performance can be
> underestimated is misleading. Everyone knew bees could fly, it was just that
> for a period it was difficult to explain via conventional aerodyanamics.

And exactly the same thing applys to this situation.  I had no idea 
that no one knew elephants couldn't go faster than 12 mph.  But I 
seen one.  Now someone is explaining how to me.

>No
> one knows that elephants can exceed 15 mph, some people just think so. What
> is more appropriate is the excessive speed claimed for the bottle fly in the
> 1920's. An entomologist standing on a mountain ridge saw one wizz by his
> head, and he timed how long it took to cross a meadow. He calculated the
> speed at 600 mph and published same in a journal. That's 600, not 60, and it
> was not a typo. No joke, I've seen the speed cited in an old Life magazine!
> Of course, a fly moving at nearly the speed of sound would have the
> characteristics of a pistol bullet - you could never see it and it sure would
> hurt awful bad when people were occasionally whacked by fast flies. Other
> scientists had a field day panning the poor fellow's mistake. The energy
> required to move so fast would be about the same as that involved in firing a
> bullet and would incinerate the bug, etc. Of course what happened was that
> the fly disappeared from the observer's view long before it reached the edge
> of the meadow so he miscalculated the distance traveled by a factor of ten,
> and did not think through the insanity of his results. Ya gotta watch out for
> those seemingly "fast" moving animals, they'll fool ya! 

I don't know what all this is really about.  There were people 
looking and publishing on the mechanics of bee flight though.  And as 
of the last time I looked they had it figured out(for the time 
being).

The point was that nobody had the mechanics of bumble bee locomotion 
down.  Perhaps this is the same thing.  You say it's impossible for 
an elephant to go faster than 12mph, but when I see it doing it, 
that's hard for me to believe.  Your facts and mine just don't agree. 
Wouldn't it be more profitable for all to figure out why? Could this 
apply to sauropod locomotion?  As a novice to the field, perhaps I 
look at things in a different manner.  I'm wrong about something 
everyday at the minimum.
> 
> As for the energy required to walk and run, for a given animal energy
> consumed is the same regardless of speed per unit distance traveled (except
> kangaroos).

That's not true.  See below.

>You burn the same number of calories walking a mile as running
> it.

That's a myth. 

That's not entirely accurate.  This is a complex matter.  Walking 
does not take into account elastic energy storage.  Quadripedal 
animals have optimum gaits at certain speeds for efficiency.  Costs 
go down initially as an animal increases locomotion then rises 
exponentially (except for hopping animals) no matter the medium of 
locomotion.  A lot of the efficiency of larger animals compared to 
smaller animals at speed is related to reduced drag in the former. 

See :

Exploring Biomechanics:   Animals in motion, NY: SciAmer Lib, McNeil, 
RA
Efficiency and Economy in Animal Physiology, Blake R, 1991, CambUniv 
Press
Animal Physiology: Eckert, 4th edit, Freeman & Co 1997

Michael

Michael Teuton
803-732-2327 Phone
803-749-6191 Fax