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Woolly mammoth
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The woolly mammoth (Mammuthus primigenius), also called the tundra mammoth, is an extinct species of mammoth. This animal is known from bones and frozen carcasses from northern North America and northern Eurasia with the best preserved carcasses in Siberia.
This mammoth species was first recorded in (possibly 150,000 years old) deposits of the second last glaciation in Eurasia. They were derived from steppe mammoths (Mammuthus trogontherii).
It disappeared from most of its range at the end of the Pleistocene, with a dwarfed race still living on Wrangel Island until roughly 1700 BCE.
ly mammoths lived in two groups (maybe subspecies).
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Encyclopedia
The woolly mammoth (Mammuthus primigenius), also called the tundra mammoth, is an extinct species of mammoth. This animal is known from bones and frozen carcasses from northern North America and northern Eurasia with the best preserved carcasses in Siberia.
This mammoth species was first recorded in (possibly 150,000 years old) deposits of the second last glaciation in Eurasia. They were derived from steppe mammoths (Mammuthus trogontherii).
It disappeared from most of its range at the end of the Pleistocene, with a dwarfed race still living on Wrangel Island until roughly 1700 BCE.
Adaptations
Woolly mammoths lived in two groups (maybe subspecies). One group stayed in the middle of the high Arctic, while the other group had a much wider range.
Woolly mammoths had a number of adaptations to the cold, most famously the thick layer of shaggy hair, up to to 1 meter in length with a fine underwool, for which the woolly mammoth is named. The coats were similar to those of Muskoxen and it is likely Mammoths moulted in summer. They also had far smaller ears than modern elephants; the largest mammoth ear found so far was only long, compared to for an African elephant. Other characteristic features included a high, peaked head that appears knob-like in many cave paintings and a high shoulder hump resulting from long spines on the neck vertebrae that probably carried fat deposits. Another feature at times found in cave paintings was confirmed by the discovery of the nearly intact remains of a baby Mammoth named "Dima". Unlike the trunk lobes of living elephants, Dima's upper lip at the tip of the trunk had a broad lobe feature, while the lower lip had a broad, squarish flap.
Their teeth were also adapted to their diet of coarse tundra grasses, with more plates and a higher crown than their southern relatives. Their skin was no thicker than that of present-day elephants, but unlike elephants they had numerous sebaceous glands in their skin which secreted greasy fat into their hair, improving its insulating qualities. They had a layer of fat up to thick under the skin which, like the blubber of whales, helped to keep them warm.
Woolly mammoths had extremely long tusks — up to long — which were markedly curved, to a much greater extent than those of elephants. It is not clear whether the tusks were a specific adaptation to their environment, but it has been suggested that mammoths may have used their tusks as shovels to clear snow from the ground and reach the vegetation buried below. This is evidenced by flat sections on the ventral surface of some tusks. It has also been observed in many specimens that there may be an amount of wear on top of the tusk that would suggests some animals had a preference as to which tusk it rested its trunk on.
Extinction
Until recently it was generally assumed that the last woolly mammoths vanished from Europe and Southern Siberia about 10,000 BCE, but new findings show that some were still present there about 8,000 BCE. Only slightly later the woolly mammoths also disappeared from continental Northern Siberia. Woolly mammoths as well as Columbian mammoths disappeared also from the North American continent at the end of the ice age.
A small population of woolly mammoths survived on St. Paul Island, Alaska, up until 3,750 BCE, while another remained on Wrangel Island, located in the Arctic Ocean, up until 1700 BCE. Possibly due to their limited food supply, these animals were a dwarf variety, thus much smaller than the original Pleistocene woolly mammoth. However, the Wrangel Island mammoths should not be confused with the Channel Islands Pygmy Mammoth, Mammuthus exilis, which was a different species.
Most woolly mammoths died out at the end of the Pleistocene, as a result of climate change and a shift in man's hunting patterns. In 2008 a study conducted by the Museo Nacional de Ciencias Naturales in Spain determined that warming temperatures had reduced mammoth habitat to only a fraction of what it once was, putting the woolly mammoth population in sharp decline before the introduction of humans into the territory. Glacial retreat shrank mammoth habitat from 42,000 years ago to 6,000 years ago. Although a similarly drastic loss of habitat occurred at the end of the Saale glaciation 125,000 years ago, human pressure during the later warming period was sufficient to push the mammoth over the brink. The study employed the use of climate models and fossil remains to make these determinations.
The Earth today has no environment similar to the habitat that sustained mammoths. In 1989 the North East science station at Cherskii in Russia began a project to recreate the steppe grassland habitat of the Pleistocene through the introduction of Yakutian horses, Bison and other steppe species. Additional to other research planned, scientists hope to clone woolly mammoths, and then re-introduce them to what is now called Pleistocene Park.
Frozen remains
The woolly mammoth is a common member in the fossil record, but unlike many others are often not actually converted to stone, but are actually preserved since their deaths. This is in part because of their massive size and partially because of the persistence of the frozen climate in which they had lived and, therefore, died.
The very first mammoth fossil fully documented by modern science, the Adams mammoth, was of this type, but had been allowed to largely decay before its recovery, possibly even having been partially devoured by modern wolves.
Preserved frozen remains of woolly mammoths, with much soft tissue remaining, have been found in the northern parts of Siberia. This is a rare occurrence, essentially requiring the animal to have been buried rapidly in liquid or semi-solids such as silt, mud and icy water which then froze. This may have occurred in a number of ways. Mammoths may have been trapped in bogs or quicksands and either died of starvation or exposure, or drowning if they sank under the surface. Though judging by the evidence of undigested food in the stomach and seed pods still in the mouth of many of the specimens, neither starvation nor exposure seem likely. The maturity of this ingested vegetation places the time period in autumn rather than in spring when flowers would be expected. The animals may have fallen through frozen ice into small ponds or potholes, entombing them. Many are certainly known to have been killed in rivers, perhaps through being swept away by river floods. In one location, by the Berelekh River in Yakutia in Siberia, more than 9,000 bones from at least 156 individual mammoths have been found in a single spot, apparently having been swept there by the current.
In 1977, the well-preserved carcass of a 7- to 8-month old baby woolly mammoth, named "Dima", was discovered. This carcass was recovered from permafrost on a tributary of the Kolyma River in northeastern Siberia. This baby woolly mammoth weighed approximately at death and was high and long. Radiocarbon dating determined that Dima died about 40,000 years ago. Its internal organs are similar to those of living elephants, but its ears are only one-tenth the size of those of an African elephant of similar age.
In the summer of 1997, a Dolgan family named Jarkov discovered a piece of mammoth tusk protruding from the tundra of the Taymyr Peninsula in Siberia, Russia. In September/October 1999 this 20,380-year-old carcass and the surrounding sediment were flown to an ice cave in Khatanga, Taymyr Autonomous Okrug. In October 2000, the careful defrosting operations in this cave began with the use of hairdryers to keep the hair and other soft tissues intact.
In May 2007, the carcass of a six-month-old female woolly mammoth calf was discovered encased in a layer of permafrost near the Yuribei River in Russia where it had been buried for 37,000 years. 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.
To date, thirty-nine preserved bodies have been found, but only four of them are complete. In most cases the flesh shows signs of decay before its freezing and later desiccation. Stories abound about frozen mammoth carcasses that were still edible once defrosted, but the original sources indicate that the carcasses were in fact terribly decayed, and the stench so unbearable that only the dogs accompanying the finders showed any interest in the flesh.
In addition to frozen carcasses, large amounts of mammoth ivory have been found in Siberia. Mammoth tusks have been articles of trade for at least 2,000 years. They have been and are still a highly prized commodity. Güyük, the 13th century Khan of the Mongols, is reputed to have sat on a throne made from mammoth ivory, and even today it is in great demand as a replacement for the now-banned export of elephant ivory.
Ivory from the extinct Wooly Mammoth has been used in the fretboards of many PRS Guitars.
The House of Staunton, purveyor of chess equipment, offers a set made from Wooly Mammoth ivory.
Genetics
Since there is a known case in which an Asian elephant and an African elephant have produced a live (though sickly) offspring, it has been theorized that if mammoths were still alive today, they would be able to interbreed with Indian elephants. This has led to the idea that perhaps a mammoth-like beast could be recreated by taking genetic material from a frozen mammoth and combining it with that from a modern Indian elephant.
Scientists hope to retrieve the preserved reproductive organs of a frozen mammoth and revive its sperm cells. However, not enough genetic material has been found in frozen mammoths for this to be attempted. Another attempt at recreating the mammoth is cloning. Fox News reported that a team of Japanese scientists feels they are getting closer to this goal. A November 4, 2008 article states that the Japanese scientists were successful in finding useful DNA of mice that had been frozen for 16 years. The scientists did so by looking in the brain, where high concentrations of sugar had preserved the DNA. They hope to use similar methods to find usable mammoth DNA and implant it into unfertilized Asian elephant eggs.
In spite of not yet being able to retrieve this usable DNA, the scientific community has been successful in determining the complete mitochondrial genome sequence of Mammuthus primigenius. The analysis demonstrates that the divergence of mammoth, African elephant, and Asian elephant occurred over a short time, and confirmed that the mammoth was more closely related to the Asian than to the African elephant. As an important landmark in this direction, in December 2005, a team of American, German, and UK researchers were able to assemble a complete mitochondrial DNA of the mammoth, which allowed them to trace the close evolutionary relationship between mammoths and the Asian elephant. African elephants branched away from the woolly mammoth around 6 million years ago, a moment in time close to that of the similar split between chimps and humans. Many researchers expect that the first fully sequenced nuclear genome of an extinct species will be that of the mammoth.
On July 6 2006 it was reported that scientists extracted, amplified and sequenced Mc1r, a gene that influences hair color in mammals, from a 43,000-year old woolly mammoth bone from Siberia.
In November 2008 it was reported that two professors from Penn State University - Stephan Schuster, professor of biochemistry and molecular biology, and Webb Miller, professor of biology, computer science and engineering - had mapped much of the woolly mammoth's DNA. Their research discovered that there were two distinct groups of woolly mammoths, one which went extinct 45,000 years ago, and a different one which went extinct in 10,000 B.C. Their research also showed that the DNA of the woolly mammoth and the African elephant are 99.4% identical.
While the authors admit they don't know the full size of the genome, they believe they have sequenced about 50% from random fragments.
The team mapped the mammoth's nuclear genome sequence by extracting DNA from the hair of a 20 000 year old mammoth retrieved from permafrost and from another mammoth which died some 60 000 years ago. Using hair avoids the problems of DNA contamination caused by bacteria and fungi. Hair produces more intact DNA because of the plastic-like protection afforded by the hair material.
Cryptozoology
There have been occasional claims that the woolly mammoth is not actually extinct, and that small isolated herds might survive in the vast and sparsely inhabited tundra of the northern hemisphere. In the late nineteenth century, there were, according to Bengt Sjögren (1962), persistent rumors about surviving mammoths hiding in Alaska. In October 1899, a story about a man named Henry Tukeman detailed his having killed a mammoth in Alaska and that he subsequently donated the specimen to the Smithsonian Institution in Washington, D.C. However, the museum denied the existence of any mammoth corpse and the story turned out to be a hoax. Sjögren (1962) believes the myth was started when the American biologist Charles Haskins Townsend traveled in Alaska, saw Eskimos trading mammoth tusks, asked if there still were living mammoths in Alaska and provided them with a drawing of the animal.
In the 19th century, several reports of "large shaggy beasts" were passed on to the Russian authorities by Siberian tribesman, but no scientific proof ever surfaced. A French chargé d'affaires working in Vladivostok, M. Gallon, claimed in 1946 that in 1920 he met a Russian fur-trapper that claimed to have seen living giant, furry "elephants" deep into the taiga. Gallon added that the fur-trapper didn't even know about mammoths before, and that he talked about the mammoths as a forest-animal at a time when they were seen as living on the tundra and snow.
In legends
Legends from dozens of Native American tribes have been interpreted by some as indicative of Proboscidea. One example is from the Kaska tribe from northern British Columbia; in 1917 an ethnologist recorded their tradition of: “A very large kind of animal which roamed the country a long time ago. It corresponded somewhat to white men's pictures of elephants. It was of huge size, in build like an elephant, had tusks, and was hairy. These animals were seen not so very long ago, it is said, generally singly; but none have been seen now for several generations. Indians come across their bones occasionally. The narrator said that he and some others, a few years ago, came on a shoulder-blade... as wide as a table (about three feet).”
External links
- , Stupid Question, February 14, 2005, by John Ruch.
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