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Re: ELEPHANTS CANNOT EXCEED ~12 MPH!



GSP1954@aol.com wrote:
> 
> 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.
> 
> 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.  

I don't doubt that this is true.  However, every reference I have (about
half a dozen, some as good as anything you'll find outside a journal)
says that the elephant has two gaits, not one: a walk for slow speeds
and an _amble_ for higher speeds.  Ambling means that the legs on the
same side are moving roughly in synch, which makes it the same as the
gait called a "pace" in horses.  This is not the same gait as a walk and
is subject to different biomechanical restrictions.  A pacing horse can
achieve better than 25mph, as demonstrated by the harness racing at any
county fair.  Several authors describe a charging elephant as fast
enough to outrun a man, and THE ILLUSTRATED ENCYCLOPEDIA OF MAMMALS
specifically says an elephant can reach 30-35kph (18.75-21.875 mph) in
an all-out charge.

> 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.

No offense intended, but a) do you know for _sure_ this is true; and b)
don't you think at least some credit should be given to observations by
reliable witnesses, even if they aren't a result of rigorous scientific
studies?

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

I have to say I find this a bit difficult to believe.  

It is also very energy expensive for an animal to maintain a constant
> speed, 4-12 times less efficient than for an animal of the same size to swim
> the same distance. Even flying is 3 times cheaper than walking in this
> regard. This is why fliers and swimmers can migrate across oceans and
> continents, while no land animal tries to do so. 

Interesting.  Does this consider the Serengeti migration?  Or the
movements of the ancient bison herds in North America?  Fpr that matter,
aren't some dinosaurs thought to have been migratory?  

-- JSW