Pygmy elephants, dwarf-like versions of elephants, were
originally thought to be an entirely different species of elephant altogether.
However, research confirms that there are currently only three living species
of elephants: Asian elephants (Elephas
maximus), Savanna elephants (Loxodonta
Africana), and Forest elephants (Loxodonta
cyclotis). So, how are pygmy elephants related to elephants who have earned an official species classification?
Borneo pygmy elephants in the Lower Kinabatangan
Wildlife Sanctuary.
Photo © Rob Colgan
There has been much debate about the classification of the
pygmy elephant. In Africa, the African pygmy elephant used to be classified as
its own species, Loxodonta pumilio,
but it has since been reclassified as a smaller-sized morph of the African
forest elephant. On the other hand, in Asia the Borneo pygmy elephant (Elephas maximus borneensis) is
considered to be a subspecies of Asian elephants, and many of them live in the
Kinabatangan River Basin (map below) in northeastern Borneo.
Many Borneo pygmy elephants live in the Kinabatangan
River Basin.
A study in 2003
by WWF and Columbia University upheld that the Borneo pygmy elephant separated
from the Asian elephant about 300,000 years ago, even though people
historically believed that the Sultan of Sulu from Java brought the elephants
in 1521 to live in Borneo. The Borneo pygmy elephant is about one meter
shorter than its mainland counterpart (the Asian elephant) and has a babyish
face and straight tusks. Supposedly, pygmy elephants are also less aggressive
than mainland Asian elephants.
Differences among African elephants, Asian elephants,
and Borneo pygmy elephants.
Photo: News.softpedia.com
What makes pygmy elephants different from dwarfs? Whereas
pygmy elephants are a subspecies and smaller version of an Asian elephant,
dwarf elephants (who were ancestors of elephant relatives) lived on isolated
islands in the Pleistocene era with few predators and resources. Their relatively
small environment (compared to that of mainland Asian elephants) with fewer
resources selected for their bodies to become reduced in size over many
generations. The inverse process of this is called gigantism, when animals—like
the dodo—become larger than normal in size in response to having a lack of
predators.
Regardless of their classification, the pygmy elephant is in
danger of becoming extinct. This is mainly due to habitat loss and
human-elephant conflict. In fact, the WWF estimates that there are fewer than
1,500 wild Borneo pygmy elephants. In addition, fourteen pygmy elephants were mysteriously
poisoned in January 2013. Pygmy elephants also suffer from habitat loss as land
is cleared to make way for palm-oil plantations.
A baby pygmy elephant investigates the body of its poisoned
mother.
References
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