I’ll start off with a few trunk facts
that any self-proclaimed follower of Think Elephants International should already
know. By definition, a trunk is the joint extension of an animal’s upper lip
and nose. The elephant’s trunk is no
exception. It can hold up to 3.7 gallons
(or 14 liters) at a time, allowing its owner to drink 10 gallons in a minute. Note,
however, that the trunk is only a holding tank and not a direct avenue through
to the esophagus. I imagine it’d be just as uncomfortable for elephants
to drink through their trunks as it is for us humans to drink through our
noses. Instead, water is simply sucked up into the trunk and then blown out
directly into the mouth. Phuki is demonstrating the trunk-to-mouth maneuver
below.
The anatomical structure of the elephant trunk claims
somewhere in the neighborhood of 150,000 muscles and is completely void of
bones. Similar muscle systems arranged along the dorsal, ventral, and both
lateral sides of the trunk allow the elephant to flex their trunk in every
direction by contracting key muscles along the corresponding side. In addition,
radially arranged muscles grant the elephant control over the total volume
available within their nasal passages, and presumably play a role in the
production of certain vocalizations.
Elephants aren’t the only animals that have evolved a trunk,
but they are certainly the largest
living species to possess the unique appendage. It may be for this very reason
that the elephant’s trunk is much longer than that of other trunked animals
such as the tapirs. Whereas the trunk may have evolved for these smaller
mammals to assist them in browsing for food, many speculate that, for
elephants, the great length of the trunk provides an elegant solution to the
problem that results when a tall animal needs to reach a water source at their
feet.
Malayan Tapir
Of course the trunk isn’t the only solution to this problem that
has been naturally selected across the animal kingdom. Consider the giraffe.
Here’s a very tall animal that manages to quench its thirst via an incredibly
long neck. Given the choice though (which of course we never are in the game of
evolution), I would much rather have a trunk with two probing nostrils at the
end than a two meter long neck with my head at the end. The benefits are the
same. Just as the giraffe can grab a bite to eat from hard to reach heights, so
can the elephant. But certainly it would seem favorable to keep your eyes and
ears in a fixed position where they can be on alert if the potential for a
predator encounter is high. I wouldn’t be very keen on drinking from a river if
it meant I had to lower both my lips and
my guard to the water’s surface.
Regardless of the how
and why behind its evolution, the
elephant trunk is certainly a spectacle. With so many adaptive features, it’s
hard to imagine any animal turning their nose up at the idea of having such a versatile
appendage.
That’s all for now… smell you later!
