User:Jaspergeli/Woolly mammoth

Woolly mammoth Temporal range: Ma PreꞒ Ꞓ O S D C P T J K Pg N ↓
Largest European specimen, a male at Südostbayerisches Naturkunde- und Mammut-Museum Siegsdorf
Scientific classification
Domain:	Eukaryota
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Proboscidea
Family:	Elephantidae
Genus:	†Mammuthus
Species:	†M. primigenius
Binomial name
†Mammuthus primigenius ( Blumenbach , 1799)
Dymaxion map showing the Late Pleistocene distribution of M. primigenius in blue (light blue was land at the time), inferred from fossil finds
Synonyms
List Elephas primigenius Blumenbach, 1799 Elephas mammonteus Cuvier, 1799 Mammuthus boreus Brookes, 1828 Mammonteus primigenius Osborn, 1924 Elephas boreus Hay, 1924

The woolly mammoth (Mammuthus primigenius) is an extinct species of mammoth that lived during the Pleistocene epoch, and was one of the last in a line of mammoth species, beginning with Mammuthus subplanifrons in the early Pliocene. The woolly mammoth diverged from the steppe mammoth about 400,000 years ago in East Asia. Its closest extant relative is the Asian elephant. The appearance and behaviour of this species are among the best studied of any prehistoric animal because of the discovery of frozen carcasses in Siberia and Alaska, as well as skeletons, teeth, stomach contents, dung, and depiction from life in prehistoric cave paintings. Mammoth remains had long been known in Asia before they became known to Europeans in the 17th century. The origin of these remains was long a matter of debate and often explained as being remains of legendary creatures. The mammoth was identified as an extinct species of elephant by Georges Cuvier in 1796.

The woolly mammoth was roughly the same size as modern

, which stretched across northern Eurasia and North America.

The woolly mammoth coexisted with early humans, who used its bones and tusks for making art, tools, and dwellings, and the species was also hunted for food. It disappeared from its mainland range at the end of the Pleistocene 10,000 years ago, most likely through climate change and consequent shrinkage of its habitat, hunting by humans, or a combination of the two. Isolated populations survived on

until 4,000 years ago. After its extinction, humans continued using its ivory as a raw material, a tradition that continues today. It has been proposed the species could be recreated through various means, but none of these are yet feasible.

Taxonomy

Remains of various extinct elephants were known by Europeans for centuries but were generally interpreted, based on

and no longer existed, a concept that was not widely accepted at the time.

Following Cuvier's identification, the German naturalist

") given to Jefferson in 1802.

lectotype molars by Henry Fairfield Osborn

. The left one is now lost.

The taxonomy of extinct elephants was complicated by the early 20th century, and in 1942, the American paleontologist

designation of E. primigenius were also proposed. The paralectotype molar (specimen GZG.V.010.018) has since been located in the Göttingen University collection, identified by comparing it with Osborn's illustration of a cast.

Evolution

The earliest known members of Proboscidea, the

in the neck:

American mastodon

(right)

In 2005, researchers assembled a complete

were confidently identified for the first time, collected from a 43,000-year-old woolly mammoth.

Staatliches Museum für Naturkunde Stuttgart

Since many remains of each species of the mammoth are known from several localities, it is possible to reconstruct the evolutionary history of the genus through

(Mammuthus columbi) are the culmination of this process.

The first known members of the genus Mammuthus are the African species

and entered North America about 1.5 million years ago; it retained a similar number of molar ridges. Mammoths derived from M. trogontherii evolved molars with 26 ridges 400,000 years ago in Siberia and became the woolly mammoth. Woolly mammoths entered North America about 100,000 years ago.

Individuals and populations showing transitional morphologies between each of the mammoth species are known, and primitive and

". Many taxa intermediate between M. primigenius and other mammoths have also been proposed, but their validity is uncertain; depending on the author, they are either considered primitive forms of an advanced species or advanced forms of a primitive species. Distinguishing and determining these intermediate forms has been called one of the most long lasting and complicated problems in Quaternary palaeontology. Regional and intermediate species and subspecies such as M. intermedius, M. chosaricus, M. p. primigenius, M. p. jatzkovi, M. p. sibiricus, M. p. fraasi, M. p. leith-adamsi, M. p. hydruntinus, M. p. astensis, M. p. americanus, M. p. compressus, and M. p. alaskensis have been proposed.

A 2011 genetic study showed that two examined specimens of the Columbian mammoth were grouped within a subclade of woolly mammoths. This suggests that the two populations interbred and produced fertile offspring. A North American type formerly referred to as M. jeffersonii may be a hybrid between the two species. A 2015 study suggested that the animals in the range where M. columbi and M. primigenius overlapped formed a metapopulation of hybrids with varying morphology. It also suggested that Eurasian M. primigenius had a similar relationship with M. trogontherii, in areas where their range overlapped.

Description

mammoths

The appearance of the woolly mammoth is probably the best known of any prehistoric animal due to the many frozen specimens with preserved soft tissue and depictions by contemporary humans in their art. Fully grown males reached shoulder heights between 2.7 and 3.4 m (8.9 and 11.2 ft) and weighed up to 6

, but this was dismissed in a 2012 study.

Cave art depicting a woolly mammoth and other animals, from the Rouffignac Cave

, France

Woolly mammoths had several adaptations to the cold, most noticeably the layer of fur covering all parts of the body. Other adaptations to cold weather include ears that are far smaller than those of modern elephants; they were about 38 cm (15 in) long and 18–28 cm (7.1–11.0 in) across, and the ear of the 6–12 month old frozen calf "Dima" was under 13 cm (5.1 in) long. The small ears reduced heat loss and frostbite, and the tail was short for the same reason, only 36 cm (14 in) long in the "Berezovka mammoth". The tail contained 21 vertebrae, whereas the tails of modern elephants contain 28–33. Their skin was no thicker than that of present-day elephants, between 1.25 and 2.5 cm (0.49 and 0.98 in). They had a layer of fat up to 10 cm (3.9 in) thick under the skin, which helped to keep them warm. Woolly mammoths had broad flaps of skin under their tails which covered the anus; this is also seen in modern elephants.

Royal BC Museum

Other characteristic features depicted in

" was described in 2015, and it was shown that it possessed a fleshy expansion a third above the tip. Rather than oval as the rest of the trunk, this part was ellipsoidal in cross-section, and double the size in diameter. The feature was also shown to be present in two other specimens, of different sexes and ages.

Coat

Naturhistorisches Museum, Vienna

The

in their skin, which secreted oils into their hair; this would have improved the wool's insulation, repelled water, and given the fur a glossy sheen.

Preserved woolly mammoth fur is orange-brown, but this is believed to be an artifact from the bleaching of pigment during burial. The amount of

recessive

(partially active) one. In mammals, recessive Mc1r alleles result in light hair. Mammoths born with at least one copy of the dominant allele would have had dark coats, while those with two copies of the recessive allele would have had light coats. A 2011 study showed that light individuals would have been rare. A 2014 study instead indicated that the coloration of an individual varied from non-pigmented on the over-hairs, bi-colored, non-pigmented and mixed red-brown guard hairs, and non-pigmented under-hairs, which would give a light overall appearance.

Dentition

Woolly mammoths had very long tusks (modified

a few centimeters long at six months old, which were replaced by permanent tusks a year later. Tusk growth continued throughout life but became slower as the animal reached adulthood. The tusks grew by 2.5–15 cm (0.98–5.91 in) each year. Some cave paintings show woolly mammoths with small or no tusks, but it is unknown whether this reflected reality or was artistic license. Female Asian elephants have no tusks, but there is no fossil evidence that any adult woolly mammoths lacked them.

Woolly mammoths had four functional

. A mammoth had six sets of molars throughout a lifetime, which were replaced five times, though a few specimens with a seventh set are known. The latter condition could extend the lifespan of the individual unless the tooth consisted of only a few plates. The first molars were about the size of those of a human, 1.3 cm (0.51 in), the third were 15 cm (6 in) 15 cm (5.9 in) long, and the sixth were about 30 cm (1 ft) long and weighed 1.8 kg (4 lb). The molars grew larger and contained more ridges with each replacement. The woolly mammoth is considered to have the most complex molars among the elephants.

Distortion in the molars is the most common health problem found in woolly mammoth fossils. Sometimes the replacement was disrupted, and the molars were pushed into abnormal positions, but some animals are known to have survived this. Teeth from Britain showed that 2% of specimens had

growths.

Palaeobiology

Somme River, by Charles R. Knight, 1916, American Museum of Natural History

Adult woolly mammoths could effectively defend themselves from predators with their tusks, trunks, and size, but juveniles and weakened adults were vulnerable to pack hunters such as

" shows that the soles of the feet contained many cracks that would have helped in gripping surfaces during locomotion. Like modern elephants, woolly mammoths walked on their toes and had large, fleshy pads behind the toes.

Like modern elephants, woolly mammoths were likely very social and lived in

in Canada, showing that there were in this case almost equal numbers of adults, sub-adults, and juveniles. The adults had a stride of 2 m (6.6 ft), and the juveniles ran to keep up.

The woolly mammoth was probably the most specialized member of the family Elephantidae. They had lipopexia (fat storage) in their neck and

of the woolly mammoth was adapted to the cold, with three mutations to improve oxygen delivery around the body and prevent freezing. This feature may have helped the mammoths to live in high latitudes.

In a 2015 study, high-quality genome sequences from three Asian elephants and two woolly mammoths were compared. Approximately 1.4 million DNA nucleotide differences were found between mammoths and elephants, which affect the sequence of more than 1,600 proteins. Differences were noted in genes for a number of aspects of physiology and biology that would be relevant to Arctic survival, including the development of skin and hair, storage and metabolism of adipose tissue, and perceived temperature. Genes related to both sensing temperature and transmitting that sensation to the brain were altered. One of the heat-sensing genes encodes a protein, TRPV3, found in the skin which also affects hair growth. When inserted into human cells, the mammoth's version of the protein was found to be less sensitive to heat than the elephant's. This is consistent with a previous observation that mice lacking active TRPV3 are likely to spend more time in cooler cage locations than wild-type mice, and have wavier hair. There were also several alterations in circadian clock genes, perhaps needed to cope with the extreme polar variation in length of daylight. Similar mutations are known in other Arctic mammals, such as reindeer.

Diet

Royal BC Museum

Food at various stages of digestion has been found in the intestines of several woolly mammoths, giving a good picture of their diet. Woolly mammoths sustained themselves on plant food, mainly grass and sedges, which were supplemented with

.

C3 plants

, unlike horses and rhinos.

Scientists identified milk in the stomach and

and gradually changed to a diet of plants when they were two to three years old. This is later than in modern elephants and may be due to a higher risk of predator attack or difficulty in obtaining food during the long periods of winter darkness in high latitudes.

The molars were adapted to their diet of coarse tundra grasses, with more enamel plates and a higher crown than their earlier, southern relatives. The woolly mammoth chewed its food by using its powerful jaw muscles to move the mandible forwards and close the mouth, then backwards while opening; the sharp enamel ridges thereby cut across each other, grinding the food. The ridges were wear-resistant to enable the animal to chew large quantities of food, which often contained grit. Woolly mammoths may have used their tusks as shovels to clear snow from the ground and reach the vegetation buried below, and to break ice to drink. This is indicated on many preserved tusks by flat, polished sections up to 30 centimetres (12 in) long on the part of the surface that would have reached the ground. The tusks were also used for obtaining food in other ways, such as digging up plants and stripping off the bark.

Life history

growth rings

The lifespan of mammals is related to their size, and since modern elephants can reach the age of 60 years, the same is thought to be true for woolly mammoths which were of a similar size. The age of a mammoth can be roughly determined by counting the

of its tusks when viewed in cross-section, but this does not account for their early years, as these are represented by the tips of the tusks, which are usually worn away. In the remaining part of the tusk, each major line represents a year, and weekly and daily ones can be found in between. Dark bands correspond to summers, and it is, therefore, possible to determine the season in which a mammoth died. The growth of the tusks slowed when it became harder to forage, for example during winter, during disease, or when a male was banished from the herd (male elephants live with their herds until about the age of ten). Mammoth tusks dating to the harshest period of the last glaciation 25–20,000 years ago show slower growth rates. Woolly mammoths continued growing past adulthood, like other elephants. Unfused limb bones show that males grew until they reached the age of 40, and females grew until they were 25. The frozen calf "Dima" was 90 cm (35 in) tall when it died at the age of 6–12 months. At this age, the second set of molars would be in the process of erupting, and the first set would be worn out at 18 months of age. The third set of molars lasted for ten years, and this process was repeated until the final, sixth set emerged when the animal was 30 years old. When the last set of molars was worn out, the animal would be unable to chew and feed, and it would die of starvation. A study of North American mammoths found that they often died during winter or spring, the hardest times for northern animals to survive.

The best-preserved head of a frozen adult specimen, that of a male nicknamed the "Yukagir mammoth", shows that woolly mammoths had temporal glands between the ear and the eye. This feature indicates that, like bull elephants, male woolly mammoths also entered "musth", a period of heightened aggressiveness. The glands are used especially by males to produce an oily substance with a strong smell called temporin. Their fur may have helped in spreading the scent further.

Examination of preserved calves show that they were all born during spring and summer, and since modern elephants have

, and indicates its gestation period was similar to that of a modern elephant, and that it was born in spring.

Evidence of several different bone diseases has been found in woolly mammoths. The most common of these diseases was osteoarthritis, found in 2% of specimens. One specimen from Switzerland had several fused vertebrae as a result of this condition. The "Yukagir mammoth" had suffered from spondylitis in two vertebrae, and osteomyelitis is also known from some specimens. Several specimens have healed bone fractures, showing that the animals had survived these injuries. An abnormal number of cervical vertebrae has been found in 33% of specimens from the North Sea region, probably due to inbreeding in a declining population.

Distribution and habitat

The habitat of the woolly mammoth is known as "

(a group of herbaceous plants) were more important in the steppe-tundra than previously acknowledged, and that it was a primary food source for the ice-age megafauna.

The southernmost woolly mammoth specimen known is from the

age, woolly mammoths briefly expanded into north-east Europe, whereafter the mainland populations became extinct.

A 2008 genetic study showed that some of the woolly mammoths that entered North America through the Bering land bridge from Asia migrated back about 300,000 years ago and had replaced the previous Asian population by about 40,000 years ago, not long before the entire species became extinct. Fossils of woolly mammoths and Columbian mammoths have been found together in a few localities of North America, including the

and lived there simultaneously, or if the woolly mammoths may have entered these southern areas during times when Columbian mammoth populations were absent there.

Relationship with humans

Modern humans coexisted with woolly mammoths during the

, France. The engraving was the first widely accepted evidence for the coexistence of humans with prehistoric extinct animals and is the first contemporary depiction of such a creature known to modern science.

The woolly mammoth is the third most depicted animal in ice-age art, after horses and bison, and these images were produced between 35,000 and 11,500 years ago. Today, more than five hundred depictions of woolly mammoths are known, in media ranging from cave paintings and engravings on the walls of 46 caves in Russia, France, and Spain to engravings and sculptures (termed "

, the "straight-tusked elephant".

"Portable art" can be more accurately dated than cave art since it is found in the same deposits as tools and other ice age artifacts. The largest collection of portable mammoth art, consisting of 62 depictions on 47 plaques, was found in the 1960s at an excavated open-air camp near

spear throwers

shaped as woolly mammoths have also been found in France.

Exploitation

Mezhyrich

, exhibited in Japan

Woolly mammoth bones were used as construction material for dwellings by both Neanderthals and modern humans during the ice age. More than 70 such dwellings are known, mainly from the

Russian Plain

. The bases of the huts were circular and ranged from 8 to 24 square metres (86 to 258 sq ft). The arrangement of dwellings varied, and ranged from 1 m (3.3 ft) to 20 m (66 ft) apart, depending on location. Large bones were used as foundations for the huts, tusks for the entrances, and the roofs were probably skins held in place by bones or tusks. Some huts had floors that extended 40 cm (16 in) below ground. Some huts included fireplaces, which used bones as fuel, probably because the wood was scarce. It is possible that some of the bones used for materials came from mammoths killed by humans, but the state of the bones, and the fact that bones used to build a single dwelling varied by several thousands of years in age, suggests that they were collected remains of long-dead animals. Woolly mammoth bones were also made into various tools, furniture, and musical instruments. Large bones, such as shoulder blades, were also used to cover dead human bodies during burial.

Woolly mammoth ivory was used to create art objects. Several

, are also known. To be able to process the ivory, the large tusks had to be chopped, chiseled and split into smaller, more manageable pieces. Some ivory artifacts show that tusks had been straightened, and it is unknown how this was achieved.

Several woolly mammoth specimens show evidence of being butchered by humans, which is indicated by breaks, cut-marks, and associated stone tools. It is not known how much prehistoric humans relied on woolly mammoth meat since there were many other large herbivores available. Many mammoth carcasses may have been scavenged by humans rather than hunted. Some cave paintings show woolly mammoths in structures interpreted as pitfall traps. Few specimens show direct, unambiguous evidence of having been hunted by humans. A Siberian specimen with a spearhead embedded in its shoulder blade shows that a spear had been thrown at it with great force. A specimen from the

Palaeoamericans

.

Extinction

Most woolly mammoth populations disappeared during the late Pleistocene and early

.

DNA sequencing of remains of two mammoths, one from Siberia 44,800 years BP and one from Wrangel Island 4,300 years BP, indicates two major population crashes: one around 280,000 years ago from which the population recovered, and a second about 12,000 years ago, near the ice age's end, from which it did not. The Wrangel Island mammoths were isolated for 5000 years, and due to the small population present when the island was isolated by rising post-ice-age sea level, about 300 to 1000 individuals experienced a 20% to 30% loss of heterozygosity, and a 65% loss in mitochondrial DNA diversity. The population seems to have subsequently been stable, without suffering further significant loss of genetic diversity. Genetic evidence thus implies the extinction of this final population was sudden, rather than the culmination of a gradual decline.

Before their extinction, the Wrangel Island mammoths had accumulated numerous genetic defects due to their small population, consistent with the concept of

. In contrast, the St. Paul Island mammoth population apparently died out before human arrival because of habitat shrinkage resulting from the post-ice-age sea-level rise, perhaps in large measure as a result of a consequent reduction in the freshwater supply.

Changes in climate shrank suitable mammoth habitat from 7,700,000 km² (3,000,000 sq mi) 42,000 years ago to 800,000 km² (310,000 sq mi) 6,000 years ago. Woolly mammoths survived an even greater loss of habitat at the end of the

trackway

in south-western Canada showed that M. primigenius was in decline while coexisting with humans since far fewer tracks of juveniles were identified than it would be expected in a normal herd.

The decline of the woolly mammoth could have increased temperatures by up to 0.2 °C (0.36 °F) at high latitudes in the northern hemisphere. Mammoths frequently ate birch trees, creating a grassland habitat. With the disappearance of mammoths, birch forests, which absorb more sunlight than grasslands, expanded, leading to regional warming.

Fossil specimens

Woolly mammoth fossils have been found in many different types of deposits, including former rivers and lakes, and also in "

, as well as mud, have also trapped mammoths in separate events over time.

Apart from frozen remains, the only soft tissue known is from a specimen that was preserved in a

" required the animal to have been buried rapidly in liquid or semi-solids such as silt, mud and icy water, which then froze.

The presence of undigested food in the stomach and seed pods that are still in the mouth of many of the specimens suggests neither starvation nor exposure is likely. The maturity of this ingested vegetation places the time of death in autumn rather than in spring when flowers would be expected. The animals may have fallen through ice into small ponds or potholes, entombing them. Many are certainly known to have been killed in rivers, perhaps through being swept away by floods. In one location, by the Berelekh River in Yakutia in Siberia, more than 8,000 bones from at least 140 mammoths have been found in a single spot, apparently having been swept there by the current.

Frozen specimens

Between 1692 and 1806, only four descriptions of frozen mammoths were published in Europe. None of the remains of those five were preserved, and no complete skeleton was recovered during that time. Schumachov let it thaw until he could retrieve the tusks for sale to the

, the museum established by Peter the Great, contained the skeleton of an Indian elephant that could be used as a reference. This was one of the first attempts at reconstructing the skeleton of an extinct animal. Most of the reconstruction is correct, but Tilesius placed each tusk in the opposite socket so that they curved outward instead of inward. The error was not corrected until 1899, and the correct placement of mammoth tusks was still a matter of debate into the twentieth century.

Museum of Zoology, St. Petersburg

The 1901 excavation of the "Berezovka mammoth" is the best documented of the early finds. It was discovered at the Siberian

Berezovka River

, and the Russian authorities financed its excavation. Its head was exposed, and the flesh had been scavenged. The animal still had grass between its teeth and on the tongue, showing that it had died suddenly. The entire expedition took 10 months, and the specimen had to be cut to pieces before it could be transported to St. Petersburg. It was identified as a 35- to 40-year-old male, which had died 35,000 years ago. One of its shoulder blades was broken, which may have happened when it fell into a crevasse.

By 1929, the remains of 34 mammoths with frozen soft tissues (skin, flesh, or organs) had been documented. Only four of them were relatively complete. Since then, about that much more have been found. In most cases, the flesh showed signs of decay before its freezing and later desiccation. Since 1860, Russian authorities have offered rewards of up to 1000 ₽ for finds of frozen woolly mammoth carcasses. Often such finds were kept secret due to superstition. Several carcasses have been lost because they were not reported, and one was fed to dogs. In more recent years, scientific expeditions have been devoted to finding carcasses instead of relying solely on chance encounters. The most famous frozen specimen from Alaska is a calf nicknamed "Effie", which was found in 1948. It consists of the head, trunk, and a foreleg, and is about 25,000 years old.

In 1977, the well-preserved carcass of a seven- to an eight-month-old woolly mammoth calf named "Dima" was discovered. This carcass was recovered near a tributary of the

in 1988. It was 3–4 months old, and a laceration on its right foot may have been the cause of death. It is the westernmost frozen mammoth found.

In 1997, a piece of mammoth tusk was discovered protruding from the tundra of the Taymyr Peninsula in Siberia, Russia. In 1999, this 20,380-year-old carcass and 25 tons of surrounding sediment were transported by an Mi-26 heavy lift helicopter to an ice cave in Khatanga. The specimen was nicknamed the "Jarkov mammoth". In October 2000, the careful defrosting operations in this cave began with the use of hair dryers to keep the hair and other soft tissues intact.

In 2002, a well-preserved carcass was discovered near the Maxunuokha River in northern Yakutia, which was recovered during three excavations. This adult male specimen was called the "Yukagir mammoth", and is estimated to have lived around 18,560 years ago, and to have been 282.9 cm (9.2 ft) tall at the shoulder, and weighed between 4 and 5 tonnes. It is one of the best-preserved mammoths ever found due to the almost complete head, covered in skin, but without the trunk. Some postcranial remains were also found, some with soft tissue.

In 2007, the carcass of a female calf nicknamed "Lyuba" was discovered near the Yuribey River, where it had been buried for 41,800 years. By cutting a section through a molar and analyzing its growth lines, they found that the animal had died at the age of one month. The mummified calf weighed 50 kg (110 lb), was 85 cm (33 in) high and 130 cm (51 in) in length. At the time of discovery, its eyes and trunk were intact and some fur remained on its body. Its organs and skin are very well preserved. "Lyuba" is believed to have been suffocated by mud in a river that its herd was crossing. After death, its body may have been colonized by bacteria that produce lactic acid, which "pickled" it, preserving the mammoth in a nearly pristine state.

In 2012, a juvenile was found in Siberia, which had man-made cut marks. Scientists estimated its age at death to be 2.5 years, and nicknamed it "Yuka". Its skull and pelvis had been removed prior to discovery but were found nearby. After being discovered, the skin of "Yuka" was prepared to produce a taxidermy mount. Another mammoth discovery was reported in October 2012, when it was excavated on the Taymyr Peninsula. It was dated to 30,000 years old. Formally known as the Sopkarga mammoth, it was nicknamed "Zhenya" after the boy who found it.

In 2013, a well-preserved carcass was found on Maly Lyakhovsky Island, one of the islands in the New Siberian Islands archipelago, a female between 50 and 60 years old at the time of death. The carcass contained well-preserved muscular tissue. When it was extracted from the ice, liquid blood spilled from the abdominal cavity. The finders interpreted this as indicating woolly mammoth blood possessed anti-freezing properties.

Recreating the species

Naturkundemuseum Stuttgart

The existence of frozen soft tissue remains and DNA of woolly mammoths has led to the idea that the species could be recreated by scientific means. Several methods have been proposed to achieve this.

. For example, Akira Iritani, at the Kyoto University in Japan, reportedly planned to do this. The cell would then be stimulated into dividing, and implanted in a female elephant. The resulting calf would have the genes of the woolly mammoth. However, nobody has yet found a viable mammoth cell, and most scientists doubt that any living cell could have survived freezing in the tundra. Because of their conditions of preservation, the DNA of frozen mammoths has deteriorated significantly.

A second method involves

, but it died of defects at less than two weeks old. The fact that sperm cells of modern mammals are viable for 15 years at most after deep-freezing makes this method unfeasible.

In April 2015, Swedish scientists published the complete

, and hair attributes. By February 2017, Church's team had made 45 substitutions to the elephant genome. So far his work focuses solely on single cells.

The Mammoth Genome Project at

gregarious

, creating a few specimens would not be ideal. The time and resources required would be enormous, and the scientific benefits would be unclear, suggesting these resources should instead be used to preserve extant elephant species which are endangered. The ethics of using elephants as surrogate mothers in hybridization attempts have also been questioned, as most embryos would not survive, and it would be impossible to know the exact needs of a hybrid elephant-mammoth calf.

Cultural significance

The woolly mammoth has remained culturally significant long after its extinction.

, as yin shu, "the hidden rodent".

The

of extinct elephants, though other scholars are sceptical that folk memory could survive such a long time.

Siberian mammoth ivory is reported to have been exported to Russia and Europe in the 10th century. The first Siberian ivory to reach western Europe was brought to London in 1611. When Russia occupied Siberia, the ivory trade grew and it became a widely exported commodity, with huge amounts being excavated. From the 19th century and onwards, woolly mammoth ivory became a highly prized commodity, used as raw material for many products. Today it is still in great demand as a replacement for the now-banned export of elephant ivory, and has been referred to as "white gold". Local dealers estimate that there are 10 million mammoths still frozen in Siberia, and conservationists have suggested that this could help save the living species of elephants from extinction. Elephants are hunted by poachers for their ivory, but if this could instead be supplied by the already extinct mammoths, the demand could instead be met by these. Trade in elephant ivory has been forbidden in most places following the 1989

global warming

has made access to Siberian tusks easier, since the permafrost thaws more quickly, exposing the mammoths embedded within it.

Stories abound about frozen woolly mammoth meat that was consumed once defrosted, especially that of the "Berezovka mammoth", but most of these are considered dubious. The carcasses were in most cases decayed, and the stench so unbearable that only wild scavengers and the dogs accompanying the finders showed any interest in the flesh. It appears that such meat was once recommended against illness in China, and Siberian natives have occasionally cooked the meat of frozen carcasses they discovered.

Alleged survival

There have been occasional claims that the woolly mammoth is not extinct, and that small isolated herds might survive in the vast and sparsely inhabited tundra of the Northern Hemisphere. In the 19th century, several reports of "large shaggy beasts" were passed on to the Russian authorities by Siberian tribesmen, but no scientific proof ever surfaced. A French chargé d'affaires working in Vladivostok, M. Gallon, said in 1946 that in 1920 he had met a Russian fur-trapper who claimed to have seen living giant, furry "elephants" deep into the taiga. Gallon added that the fur-trapper had not heard of mammoths before. Due to the large area of Siberia, it cannot be completely ruled out that woolly mammoths survived into more recent times, but all evidence indicates that they became extinct thousands of years ago. It is likely that these natives had gained their knowledge of woolly mammoths from carcasses they encountered, and that this is the source for their legends of the animal.

In the late 19th century, there were rumors about surviving mammoths in Alaska. In October 1899, Henry Tukeman detailed his killing of a mammoth in Alaska and his subsequent donation of the specimen to the Smithsonian Institution in Washington, D.C.. The museum denied the story. Bengt Sjögren believed that the myth began when the American biologist Charles Haskins Townsend traveled in Alaska, saw Eskimos trading mammoth tusks, asked if there were still living mammoths in Alaska, and provided them with a drawing of the animal.