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Mammoth remains have been found in Europe, Africa, Asia, and
North America. They are believed to have originally evolved in
North Africa about 4.8 million years ago, during the Pliocene,
where bones of Mammuthus africanavus have been found in Chad,
Libya, Morocco and Tunisia. Mammuthus subplanifrons, found in
South Africa and Kenya, is also believed to be one of the oldest
species (about 4 million years ago).
Despite their African ancestry, they are in fact more closely
related to the modern Asian Elephant than either of the two
African elephants (as both Mammuthus and Elephas also originated
in Africa). The common ancestor of both mammoths and Asian
elephants split from the line of African elephants in the Late
Miocene about 6 - 7.3 million years ago, probably due to the
uplift of East Africa and increasing aridity in the Middle East.
The Asian elephants and mammoths diverged about half a million
years later, i.e. 5.5 - 6.3 million years ago.(Capelli et al.
2006)
In due course the African mammoth migrated north to Europe and
gave rise to a new species, the southern mammoth (Mammuthus
meridionalis). This eventually spread across Europe and Asia and
crossed the now-submerged Bering Land Bridge into North America.
Around 700,000 years ago, the warm climate of the time
deteriorated markedly and the savannah plains of Europe, Asia
and North America gave way to colder and less fertile steppes.
The southern mammoth consequently declined, being replaced
across most of its territory by the cold-adapted steppe mammoth
(Mammuthus trogontherii). This in turn gave rise to the woolly
mammoth, Mammuthus primigenius) around 300,000 years ago. Woolly
mammoths were better able to cope with the extreme cold of the
Ice Ages.
The woollies were a spectacularly successful species; they
ranged from Spain to North America and are thought to have
existed in huge numbers. The Russian researcher Sergei Zimov
estimates that during the last Ice Age, parts of Siberia may
have had an average population density of sixty animals per
hundred square kilometres - equivalent to African elephants
today.
Most mammoths died out at the end of the last Ice Age. A
definitive explanation for their mass extinction is yet to be
agreed upon. A small population survived on St. Paul Island,
Alaska, up until 6000 BC, and the small mammoths of Wrangel
Island became extinct only around 2500 BC.
Whether the general mammoth population died out for climatic
reasons or due to over hunting by humans is controversial.
Another theory suggests that mammoths may have fallen victim to
an infectious disease. A combination of climate change and
hunting by humans is probably the most likely explanation for
their extinction.
New data derived from studies done on living elephants (see Levy
2006) suggests that though human hunting may not have been the
primary cause toward the mammoth's final extinction, human
hunting was likely a strong contributing factor. Homo erectus is
known to have consumed mammoth meat as early as 1.8 million
years ago (Levy 2006: 295).
However, the American Institute of Biological Sciences also
notes that bones of dead elephants, left on the ground and
subsequently trampled by other elephants, tend to bear marks
resembling butchery marks, which have previously been
misinterpreted as such by archaeologists.
The survival of the dwarf mammoths on Russia's Wrangel Island
was due to the fact that the island was very remote, and
uninhabited in the early Holocene period. The actual island was
not discovered by modern civilization until the 1820s by
American whalers. A similar dwarfing occurred with Mammoths on
the outer Channel Islands of California, but at an earlier
period. Those animals were very likely killed by early Paleo-Native
Americans, and habitat loss caused by a rising sea level that
split the Santa Rosae into the outer Channel Islands.
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It is a common misconception that mammoths were much larger than
modern elephants, an error that has led to "mammoth" being used
as an adjective meaning "very big". Certainly, the largest known
species, the Imperial Mammoth of California, reached heights of
at least 5 meters (16 feet) at the shoulder. Mammoths would
probably normally weigh in the region of 6 to 8 tonnes, but
exceptionally large males may have exceeded 12 tonnes. A 3.3 m.
(11 ft.) long mammoth tusk was discovered north of Lincoln,
Illinois in 2005. However, most species of mammoth were only
about as large as a modern Asian Elephant. Fossils of species of
dwarf mammoth have been found on the Californian Channel Islands
(Mammuthus exilis) and the Mediterranean island of Sardinia (Mammuthus
lamarmorae). There was also a race of dwarf woolly mammoths on
Wrangel Island, north of Siberia, within the Arctic Circle.
Based on studies of their close relatives, the modern elephants,
mammoths probably had a gestation period of 22 months, resulting
in a single calf being born. Their social structure was probably
the same as that of African and Asian elephants, with females
living in herds headed by a matriarch, whilst bulls lived
solitary lives or formed loose groups after sexual maturity.
In May 2007, the 10,000 year old carcass of a six-month-old
female mammoth calf was discovered encased in a layer of
permafrost near the Yuribei River in Russia. Alexei Tikhonov,
the Russian Academy of Science's Zoological Institute's deputy
director has dismissed the prospect of cloning the animal, as
the whole cells required for cloning would have burst under the
freezing conditions. DNA is expected to be well-preserved enough
to be useful for research on mammoth phylogeny and perhaps
physiology however.

This Mammoth Page is Copyright The Animal Web Guide © 2004 - 2009 Chuck Ayoub