begin quote from:
https://en.wikipedia.org/wiki/Mammoth
Extinction
The
woolly mammoth (
M. primigenius) was the last species of the genus. Most populations of the woolly mammoth in North America and Eurasia, as well as all the
Columbian mammoths (
M. columbi) in North America, died out around the time of the last
glacial retreat, as part of a
mass extinction of
megafauna
in northern Eurasia and the Americas. Until recently, the last woolly
mammoths were generally assumed to have vanished from Europe and
southern Siberia about 12,000 years ago, but new findings show some were
still present there about 10,000 years ago. Slightly later, the woolly
mammoths also disappeared from continental northern Siberia.
[23] A small population survived on
St. Paul Island, Alaska, up until 3750 BC,
[2][24][25] and the small
[26] mammoths of
Wrangel Island survived until 1650 BC.
[27][28] Recent research of sediments in Alaska indicates mammoths survived on the American mainland until 10,000 years ago.
[29]
A definitive explanation for their extinction has yet to be agreed.
The warming trend (Holocene) that occurred 12,000 years ago, accompanied
by a glacial retreat and rising sea levels, has been suggested as a
contributing factor. Forests replaced open woodlands and grasslands
across the continent. The available habitat would have been reduced for
some megafaunal species, such as the mammoth. However, such climate
changes were nothing new; numerous
very similar warming episodes had occurred previously within the
ice age
of the last several million years without producing comparable
megafaunal extinctions, so climate alone is unlikely to have played a
decisive role.
[30][31] The spread of advanced human hunters through northern
Eurasia and the
Americas around the time of the extinctions, however, was a new development, and thus might have contributed significantly.
[30][31]
Mammuthus primigenius "Hebior Mammoth specimen" bearing tool/butcher marks
Whether the general mammoth population died out for climatic reasons or due to
overhunting by humans is controversial.
[32]
During the transition from the Late Pleistocene epoch to the Holocene
epoch, there was shrinkage of the distribution of the mammoth because
progressive warming at the end of the Pleistocene epoch changed the
mammoth's environment. The
mammoth steppe
was a periglacial landscape with rich herb and grass vegetation that
disappeared along with the mammoth because of environmental changes in
the climate. Mammoths had moved to isolated spots in Eurasia, where they
disappeared completely. Also, it is thought that Late Paleolithic and
Mesolithic human hunters might have affected the size of the last
mammoth populations in Europe.
[citation needed]
There is evidence to suggest that humans did cause the mammoth
extinction, although there is no definitive proof. It was found that
humans living south of a mammoth steppe learned to adapt themselves to
the harsher climates north of the steppe, where mammoths resided. It was
concluded that if humans could survive the harsh north climate of that
particular mammoth steppe then it was possible humans could hunt (and
eventually extinguish) mammoths everywhere. Another hypothesis suggests
mammoths fell victim to an infectious disease. A combination of
climate change and hunting by humans may be a possible explanation for their extinction.
Homo erectus is known to have consumed mammoth meat as early as 1.8 million years ago,
[33]
though this may mean only successful scavenging, rather than actual
hunting. Later humans show greater evidence for hunting mammoths;
mammoth bones at a 50,000-year-old site in South Britain suggest that
Neanderthals butchered the animals,
[34] while various sites in Eastern Europe dating from 15,000 to 44,000 years old suggest humans (probably
Homo sapiens) built dwellings using mammoth bones (the age of some of the earlier structures suggests that Neanderthals began the practice).
[35] However, the
American Institute of Biological Sciences
also notes 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.
[citation needed]
Many hypotheses also seek to explain the regional extinction of
mammoths in specific areas. Scientists have speculated that the mammoths
of
Saint Paul Island,
an isolated enclave where mammoths survived until about 8,000 years
ago, died out as the island shrank by 80–90% when sea levels rose,
eventually making it too small to support a viable population.
[36]
Similarly, genome sequences of the Wrangel Island mammoths indicate a
sharp decline in genetic diversity, though the extent to which this
played a role in their extinction is still unclear.
[37]
Another hypothesis, said to be the cause of mammoth extinction in
Siberia, comes from the idea that many may have drowned. While traveling
to the Northern River, many of these mammoths broke through the ice and
drowned. This also explains bones remains in the Arctic Coast and
islands of the New Siberian Group.
[citation needed]
Dwarfing occurred with the
pygmy mammoth 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
Santa Rosae into the outer Channel Islands.
[citation needed]
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