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THOSE ELEPHANTS ARE NOT GETTING FASTER



I am afraid that the arguments being expressed by Michael and others are
examples of a problem with the Internet, opinions are expressed as though
they have scientific content when they may not. 

As far as I know Michael has presented no actual data confirming his claim to
have seen an elephant move as fast as the fastest Olympic sprinters (which do
~22.5 mph in the 100 m). No film, no measured course, nada. Until he does so
he is just arm waving. Nor has Kingdon presented such data, or has anyone
else. The 25 mph speeds often cited in the literature are prime examples of
repeated nondata, there is no primary well documented source. Those who have
worked on animal locomotion such as Garland and Alexander have always
expressed skepticism at such speeds. 

Rhinos certainly are much faster than elephants, but that does not mean that
elephants are fast. I have timed rhinos in video galloping for some distance
at less than 20 mph, they probably cannot charge must faster than 25 to
*maybe* 30 mph. For that matter, Alexander et al (1977, J. Zoology 183:291)
in a large study of speed in African ungulates in the field could not get
them to go faster than 30 mph when chasing them with a land rover. The notion
that fast walking elephants can move at anywhere near the speed of galloping
rhinos and other ungulates - much less as fast as sprinting Olympians - is
nonsense. 

The scientific burden of proof IS upon those who wish to show that elephants
can walk as fast as galloping ungulates and the fastest atheletes. It is an
extraordinary claim so far without documentation. Unsubstantiated &
extraordinary claims must be backed up with firm evidence before they can be
accepted. The asssertions that we should not discount eyewitness accounts of
fast elephants are similar to the claims that we should not discount
eyewitness accounts of aliens, psychic events, and near sonic bottle flies. 

The elephant I timed was not, as Betty suggested, slow. It won the elephant
race! 

Elephants do not, as Jonathon suggested, pace like giraffes, camels or
trained horses. A pace is the functional equivalent of a trot, and includes a
suspended phase. The elephantine amble is a slightly modified and sped up
walk that includes no suspended phase, because at least one foot always
contacts the ground. 

Michael displays a disturbing lack of knowledge when he denies that the cost
of walking and running a given distance is the same in a given animal. Also
spurious is his claim that the cost of locomotion follows an exponential
curve, and that drag hinders speed in small animals. Schmidt-Nielsen (1984,
Scaling: Why is Animal Size so Important? Cambridge Univ P) stated that
"energy expenditure increases linearly with running speed", and Fig. 14 shows
lots of nice straight lines for a variety of animals, none of the dips and
swoops Micheal describes. S-N further stated that "the cost of
running......is independent of the speed at which an animal runs". As I
noted, there are only minor deviations from this rule. People tend to walk at
3 mph because it is *just* a little more energy efficient than faster or
slower speeds.  

The linear speed/energy cost relationship has been known for three decades.
I've known about it since the 70s, its old news. It is therefore exasperating
when someone makes spurious misstatements about well established facts of
animal locomotion. Considering Michael's weak knowledge base on animal
locomotion, I suggest others treat his claims that he has shown how elephants
can walk at 25 mph with skepticism. For example, he asserts that elephants
"lift their hips" in order to "accelerate" their limbs twice as fast as a
pendulem would allow. Of course, this does nothing for the forelimbs, which
carrry most of the mass in elephants. Nor is it clear that Michael has
actually documented his claim of exceptionally fast leg action in elephants.
Present the video at a scientific forum.   

Turning to speed of sauropods, it is highly improbable they were any faster
or slower than elephants, and could do about 12 mph. Sauropods were as short
backed as elephants relative to the length of their limbs, and very probably
could amble.  

GSPaul