Woolly mammoth

From Wikipedia, the free encyclopedia
  (Redirected from Mammuthus primigenius)
Jump to: navigation, search
Woolly mammoth
Temporal range: Pleistocene - Early Holocene 0.15–0.004Ma
Siegsdorfer Mammut.jpg
Largest European specimen, a male from Siegsdorf
Scientific classification e
Kingdom: Animalia
Phylum: Chordata
Class: Mammalia
Order: Proboscidea
Family: Elephantidae
Genus: Mammuthus
Species: M. primigenius
Binomial name
Mammuthus primigenius
(Blumenbach, 1799)
Distribution of woolly mammoth.png
Distribution during the last glacial period
Synonyms
  • Elephas primigenius Blumenbach, 1799
  • Mammonteus primigenius (Osborn, 1924)
  • Elephas boreus Hay, 1924
  • Mammuthus boreus (Hay, 1924)

The woolly mammoth (Mammuthus primigenius) was a species of mammoth, the common name for the extinct elephant genus Mammuthus. The woolly mammoth was one of the last in a line of mammoth species, beginning with Mammuthus subplanifrons in the early Pliocene. M. primigenius diverged from the steppe mammoth, M. trogontherii, about 200,000 years ago in eastern 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 due to 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 animal was only identified as an extinct species of elephant by Georges Cuvier in 1796.

The woolly mammoth was roughly the same size as modern African elephants. Males reached shoulder heights between 2.7 and 3.4 m (9 and 11 ft) and weighed up to 6 tonnes (6.6 tons). Females averaged 2.6–2.9 metres (8.5–9.5 ft) in height and weighed up to 4 tonnes (4.4 tons). A newborn calf weighed about 90 kilograms (200 lb). The woolly mammoth was well adapted to the cold environment during the last ice age. It was covered in fur, with an outer covering of long guard hairs and a shorter undercoat. The colour of the coat varied from dark to light. The ears and tail were short to minimise frostbite and heat loss. It had long, curved tusks and four molars, which were replaced six times during the lifetime of an individual. Its behaviour was similar to that of modern elephants, and it used its tusks and trunk for manipulating objects, fighting, and foraging. The diet of the woolly mammoth was mainly grass and sedges. Specimens could probably reach the age of 60. Its habitat was the mammoth steppe, 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.[1] It disappeared from its mainland range at the end of the Pleistocene 10,000 years ago, most likely through a combination of climate change, consequent disappearance of its habitat, and hunting by humans, though the significance of these factors is disputed. Isolated populations survived on Wrangel Island until 4,000 years ago, and on St. Paul Island until 6,400 years ago. After its extinction, humans continued using its ivory as a raw material, and this tradition continues today. It has been proposed the species could be recreated through cloning, but this method is as yet infeasible due to the degraded state of the remaining genetic material. The ethics of such an operation have also been questioned.

Taxonomy[edit]

A mammoth tusk with Inuit carvings of scenes on the Yukon River, 19th century

Remains of various extinct elephants were known by Europeans for centuries, but were generally interpreted, based on biblical accounts, as the remains of legendary creatures such as behemoths or giants. It was also theorised that they were remains of modern elephants that had been brought to Europe during the Roman Republic, for example the war elephants of Hannibal the Great and Pyrrhus of Epirus, or animals that had wandered north.[2] The first woolly mammoth remains studied by European scientists were examined by Hans Sloane in 1728 and consisted of fossilised teeth and tusks from Siberia. Sloane was the first to recognise that the remains belonged to elephants.[3] Sloane turned to another biblical explanation for the presence of elephants in the Arctic, asserting that they had been buried during the Great Flood, and that Siberia had previously been tropical prior to a drastic climate change.[4] Others interpreted Sloane's conclusion slightly differently, arguing the flood had carried elephants from the Tropics to the Arctic. Sloane's paper was based on travellers' descriptions and a few scattered bones collected in Siberia and Britain. He discussed the question of whether or not the remains were from elephants, but drew no conclusions.[5]

In 1738, Johann Philipp Breyne argued that mammoth fossils represented some kind of elephant. He could not explain why a tropical animal would be found in such a cold area as Siberia, and suggested that they might have been transported there by the Great Flood.[6] In 1796, French anatomist Georges Cuvier was the first to identify the woolly mammoth remains not as modern elephants transported to the Arctic, but as an entirely new species. He argued this species had gone extinct and no longer existed, a concept that was not widely accepted at the time.[2][7]

Etymology[edit]

Cuvier's 1796 comparison between the mandible of a woolly mammoth and an Indian elephant

Following Cuvier's identification, Johann Friedrich Blumenbach gave the woolly mammoth its scientific name, Elephas primigenius, in 1799, placing it in the same genus as the Asian elephant. This name means "the firstborn elephant". Henry Fairfield Osborn chose a molar from Blumenbach's collection as the lectotype specimen for the species in 1942, since holotype designation was not practised in Blumenbach's time.[8] In 1828 Joshua Brookes recognised the species was distinct enough to warrant a new genus, and reclassified it as Mammuthus primigenius.[9] It is unclear where and how the word "mammoth" originated. It may be a version of mehemot, the Arabic version of the biblical word "behemoth". Another possible origin is Estonian, where maa means earth, and mutt means mole. The word was first used in Europe during the early 17th century, when referring to maimanto tusks discovered in Siberia.[10] Thomas Jefferson, who had a keen interest in palaeontology, is partially responsible for transforming the word mammoth from a noun describing the prehistoric elephant to an adjective describing anything of surprisingly large size. The first recorded use of the word as an adjective was in a description of a wheel of cheese (the "Cheshire Mammoth Cheese") given to Jefferson in 1802.[11]

Evolution[edit]

The earliest known proboscideans, the clade which contains elephants, existed about 55 million years ago around the Tethys Sea. The closest known relatives of the Proboscidea are the sirenians and the hyraxes. The family Elephantidae existed six million years ago in Africa and includes the modern elephants and the mammoths. Among many now extinct clades, the mastodon is only a distant relative of the mammoths, and part of the separate Mammutidae family, which diverged 25 million years before the mammoths evolved.[12] The following cladogram shows the placement of the genus Mammuthus among other proboscideans, based on hyoid characteristics:[13]




Mammut (Mastodon)




Gomphotherium




Stegodon




Loxodonta (African elephant)




Elephas (Asian elephant)



Mammuthus (Mammoth)








Comparison between a woolly mammoth and an American mastodon

In 2005, researchers assembled a complete mitochondrial genome profile of the woolly mammoth, which allowed them to trace the close evolutionary relationship between mammoths and Asian elephants, Elephas maximus.[14] African elephants, Loxodonta africana, branched away from this clade around 6 million years ago, close to the time of the similar split between chimpanzees and humans. Before the publication of the Neanderthal genome, many researchers expected the first fully sequenced nuclear genome of an extinct species would be that of the mammoth.[15] A 2010 study confirmed these relationships, and suggested the mammoth and Asian elephant lineages diverged 5.8–7.8 million years ago, while African elephants diverged from an earlier common ancestor 6.6–8.8 million years ago.[16] In 2008, much of the woolly mammoth's chromosomal DNA was mapped. The analysis showed that the woolly mammoth and the African elephant are 98.55% to 99.4% identical.[17] The team mapped the woolly mammoth's nuclear genome sequence by extracting DNA from the hair follicles of both a 20,000-year-old mammoth retrieved from permafrost, and another that died 60,000 years ago.[18] In 2012, proteins were confidently identified for the first time, collected from a 43.000 old woolly mammoth.[19]

M. jeffersonii, a possible hybrid between Columbian and woolly mammoths

Since many remains of each species of mammoth are known from several localities, it is possible to reconstruct the evolutionary history of the genus through morphological studies. Mammoth species can be identified from the number of enamel ridges on their molars; primitive species had few ridges, and the number increased gradually as new species evolved and replaced the preceding ones. The crowns of the teeth lengthened and the skulls became taller to accommodate this. At the same time, the skulls became shorter from front to back to minimise the weight.[20] These adaptations were acquired gradually as mammoths turned to more abrasive food items.[21]

Cast of an intermediate form between M. trogontherii and M. primigenius, M. p. fraasi

The first known members of the genus Mammuthus are the African species M. subplanifrons from the Pliocene, and M. africanavus from the Pleistocene. The former is thought to be the ancestor of later forms. Mammoths entered Europe around 3 million years ago. The earliest type known from there has been named M. rumanus, which spread across Europe and China. Only its molars are known, which show that it had 8–10 enamel ridges. A population evolved 12–14 ridges, splitting off from and replacing the earlier type, becoming M. meridionalis. In turn, this species was replaced by the steppe mammoth, M. trogontherii, with 18–20 ridges, which evolved in eastern Asia c. 1 million years ago. Mammoths derived from M. trogontherii evolved molars with 26 ridges 200,000 years ago in Siberia and became the woolly mammoth, M. primigenius.[20] The Columbian mammoth, M. columbi, evolved from a population of M. trogontherii that had entered North America. 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 form known as M. jeffersonii may be a hybrid between the two species.[22]

Individuals and populations showing transitional morphologies between each of the mammoth species are known, and primitive and derived species coexisted as well until the former disappeared. The different species and their intermediate forms can therefore be termed "chronospecies". Many intermediate subspecies have also been proposed, but their validity is uncertain; depending on author, they are either considered primitive forms of an advanced species or advanced forms of a primitive species.[20] Regional and intermediate subspecies such as M. p. primigenius, M. p. jatzkovi, M. p. sibiricus, and M. p. fraasi have been proposed.[23] The St. Paul Island and Wrangel Island populations were described as dwarf varieties, much smaller than the mainland woolly mammoth; the Wrangel Island population was also proposed to be a new subspecies, M. p. vrangeliensis.[24][25] The Wrangel mammoths were isolated for 5000 years, but only experienced a slight loss of genetic variation.[26]

Description[edit]

Cave art from Les Combarelles, France

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 (9 and 11 ft) and weighed up to 6 tonnes (6,000 kg). This is almost as large as extant male African elephants, which commonly reach 3–3.4 m (9.8–11.2 ft), and is less than the size of the earlier mammoth species M. meridionalis and M. trogontherii, and the contemporary M. columbi. The reason for the smaller size is unknown. Female woolly mammoths averaged 2.6–2.9 m (8.5–9.5 ft) in height and were built more lightly than males, weighed up to 4 tonnes (4,000 kg). A newborn calf would have weighed about 90 kg (200 lb). These sizes are deduced from comparison with modern elephants of similar size.[27] Though the mammoths on Wrangel Island were smaller than those of the mainland, their size varied, and they were not small enough to be considered "dwarves".[28] It has been claimed that the last woolly mammoth populations decreased in size and increased their sexual dimorphism, but this was dismissed in a 2012 study.[29]

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.[30]

Model at the Royal BC Museum

Other characteristic features depicted in cave paintings include a large, high, single-domed head and a sloping back with a high shoulder hump, resulting from long spinous processes on the neck vertebrae. These features were not present in juveniles, which had concave backs like African elephants.[31] Another feature shown in cave paintings was confirmed by the discovery of a frozen specimen in 1924, an adult nicknamed the "Middle Kolyma mammoth", which was preserved with a complete trunk tip. Unlike the trunk lobes of modern elephants, the upper "finger" at the tip of the trunk had a long pointed lobe and was 10 cm (3.9 in) long, while the lower "thumb" was 5 cm (2.0 in) and was broader. The trunk of "Dima" was 76 cm (2.49 ft) long, whereas the trunk of the adult "Liakhov mammoth" was 2 metres (6.6 ft) long.[30] Few frozen specimens have preserved genitals, so the gender is usually determined through examination of the skeleton. Males were generally larger and had more robust skeletons and tusks. The best indication of sex is the size of the pelvic girdle, as the birth canal is always wider in females than in males.[32]

Coat[edit]

Fur in Naturhistorisches Museum, Vienna

The coat consisted of an outer layer of long, coarse "guard hair", which was 30 cm (12 in) on the upper part of the body, up to 90 cm (35 in) in length on the flanks and underside, and 0.5 mm (0.020 in) in diameter, and a denser inner layer of shorter, slightly curly under-wool, up to 8 cm (3.1 in) long and 0.05 mm (0.0020 in) in diameter. The hairs on the upper leg were up to 38 cm (15 in) long, and those of the feet were 15 cm (5.9 in) long, reaching the toes. The hairs on the head were relatively short, but longer on the underside and the sides of the trunk. The tail was extended by coarse hairs up to 60 cm (24 in) long, which were thicker than the guard hairs. It is likely that the woolly mammoth moulted seasonally, and that the heaviest fur was shed during spring. Since mammoth carcasses were more likely to be preserved during autumn, it is possible that only the winter coat has been preserved in frozen specimens. Modern elephants have much less hair, though juveniles have a more extensive covering of hair than adults.[33] Comparison between the over-hairs of woolly mammoths and extant elephants show that they did not differ much in overall morphology.[34] Woolly mammoths had numerous sebaceous glands 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.[35]

Preserved woolly mammoth fur is orange-brown, but this is believed to be an artefact from the bleaching of pigment during burial. The amount of pigmentation varied from hair to hair and also within each hair.[30] A 2006 study sequenced the Mc1r gene (which influences hair colour in mammals) from woolly mammoth bones. Two alleles were found: a dominant (fully active) and a recessive (partially active) one. In mammals, recessive Mc1r alleles results 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.[36] A 2011 study showed that light individuals would have been rare.[37]

Dentition[edit]

Specimen with asymmetrical tusks, the Smithsonian Museum

Woolly mammoths had very long tusks, which were more curved than those of modern elephants. The largest known male tusk is 4.2 m (14 ft) long and weighs 91 kg (201 lb), but 2.4–2.7 m (7.9–8.9 ft) and 45 kg (99 lb) was a more typical size. Female tusks averaged at 1.5–1.8 m (4.9–5.9 ft) and weighed 9 kg (20 lb). About a quarter of the length was inside the sockets. The tusks grew spirally in opposite directions from the base and continued in a curve until the tips pointed towards each other. In this way, most of the weight would have been close to the skull, and there would be less torque than with straight tusks. The tusks were usually asymmetrical and showed considerable variation, with some tusks curving down instead of outwards and some being shorter due to breakage. Calves developed small milk tusks a few centimetres 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.[38]

Molar from font de Champdamoy, France

Woolly mammoths had four functional molar teeth at a time, two in the upper jaw and two in the lower. 23 cm (9.1 in) of the crown was within the jaw, and 2.5 cm (1 in) was above. The crown was continually pushed forwards and up as it wore down, comparable to a conveyor belt. The teeth had up to 26 separated ridges of enamel, which were themselves covered in "prisms" that were directed towards the chewing surface. These were quite wear resistant and kept together by cementum and dentine. 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 only consisted of 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.[39]

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 periodontal disease, with half of these containing caries. The teeth also sometimes had cancerous growths.[40]

Palaeobiology[edit]

Restoration of a herd walking near the Somme River by Charles R. Knight

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 wolves, cave hyenas and large felines. The tusks may also have been used in intra-species fighting, such as territorial fights or fights over mates. Because of their curvature, the tusks were not suitable for stabbing, but may have been used for hitting, as indicated by injuries to some fossil shoulder blades. As in modern elephants, the sensitive and muscular trunk worked as a limb-like organ with many functions. It was used for manipulating objects, and in social interactions. The very long hairs on the tail probably compensated for the shortness of the tail, enabling its use as a flyswatter, similar to the tail on modern elephants.[41] As in reindeer and musk oxen, the haemoglobin 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.[42]

Mounted "family group"

Like modern elephants, woolly mammoths were likely very social and lived in matriarchal family groups. This is supported by fossil assemblages and cave paintings showing groups. It is therefore probable that most of their other social behaviour was similar to those of modern elephants. Accumulations of modern elephant remains have been termed "elephants' graveyards", as these sites were erroneously thought to be where old elephants went to die. Similar accumulations of woolly mammoth bones have been found; it is thought these are the result of individuals dying near or in the rivers over thousands of years, and their bones eventually being brought together by the streams, or due to animals being mired in mud. Some accumulations are also thought to be the remains of herds that died together at the same time, perhaps due to flooding.[43]

Leg and foot of the "Yukagir mammoth"

Trackways made by a woolly mammoth herd 11,300–11,000 years ago, have been found in the St. Mary Reservoir 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.[44] The well-preserved foot of the adult male "Yukagir mammoth" 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.[30]

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.[45] Parasitic flies and protozoa were identified in the gut of the calf "Dima".[46]

Diet[edit]

The frozen calf "Lyuba" which still had food in its stomach

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 herbaceous plants, flowering plants, shrubs, mosses, and tree matter. The composition and exact varieties differed from location to location. Woolly mammoths needed a varied diet to support their growth, like modern elephants. An adult of six tonnes would need to eat 180 kg (397 lb) daily, and may have foraged as long as twenty hours every day. The two-fingered tip of the trunk was probably adapted for picking up the short grasses of the last ice age (Quaternary glaciation, 2.58 million years ago to present) by wrapping around them, whereas modern elephants curl their trunks around the longer grass of their tropical environments. The trunk could also be used for pulling off large grass tufts, delicately picking buds and flowers, and tearing off leaves and branches where trees and shrubs were present. The "Yukagir mammoth" had ingested plant matter that contained spores of dung fungus.[47] Isotope analysis shows that woolly mammoths fed mainly on C3 plants, unlike horses and rhinos.[48]

Mandible in Barcelona

Scientists identified milk in the stomach and faecal matter in the intestines of the mammoth calf "Lyuba".[49] The faecal matter may have been eaten by "Lyuba" to promote development of the intestinal microbes necessary for digestion of vegetation, as is the case in modern elephants.[50] An isotope analysis of woolly mammoths from Yukon, Canada, showed that the young nursed for at least three years, and were weaned 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.[51]

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, which made the sharp enamel ridges cut across each other and grind 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 bark.[52]

Growth and reproduction[edit]

Cross sectioned tusk with growth rings

The age of a woolly mammoth can be determined by counting the growth rings of its tusks when viewed in cross section. 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 disease, when a male was banished from the herd, and during periods of severe glaciation. 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. A woolly mammoth could probably reach the age of 60, like modern elephants of the same size. By then the last set of molars would be worn out, the animal would be unable to chew and feed, and it would die of starvation.[53]

Head of the "Yukagir mammoth"

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.[54] This feature indicates that male woolly mammoths also entered "musth", during which bull elephants become very aggressive. 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.[55]

Examination of preserved calves show that they were all born during spring and summer, and since modern elephants have gestation periods of 21–22 months, it is probable that the mating season was from summer to autumn.[56] δ15N isotopic analysis of the teeth of "Lyuba" has demonstrated their prenatal development, and indicates its gestation period was similar to that of a modern elephant, and that it was born in spring.[57]

Distribution and habitat[edit]

Restoration of a group in late Pleistocene northern Spain, by Mauricio Antón

The habitat of the woolly mammoth is known as "mammoth steppe" or "tundra steppe". This environment stretched across northern Asia, many parts of Europe, and the northern part of North America during the last ice age. It was similar to the grassy steppes of modern Russia, but the flora was more diverse, abundant, and grew faster. Grasses, sedges, shrubs, and herbaceous plants were present, and scattered trees were mainly found in southern regions. This habitat was not dominated by ice and snow, as is popularly believed, since these regions are thought to have been high-pressure areas at the time. The habitat of the woolly mammoth also supported other grazing herbivores such as the woolly rhinoceros, wild horses and bison. Woolly mammoths have been found in the same locations as those of the Columbian mammoth in North America, but it is unknown whether the two species were sympatric. The woolly mammoth may have entered these southern areas during times when Columbian mammoth populations were absent.[58] The southernmost woolly mammoth specimen known is from the Shandong province of China, and is 33,000 years old.[59] The southernmost European remains are from the Granada Basin of Spain and are of roughly the same age.[60]

DNA studies have helped determine the phylogeography of the woolly mammoth. A 2008 DNA study showed there were two distinct groups of woolly mammoths: one that went extinct 45,000 years ago and another one that went extinct 12,000 years ago. The two groups are speculated to be divergent enough to be characterised as subspecies. The group that went extinct earlier stayed in the middle of the high Arctic, while the group with the later extinction had a much wider range.[61] Recent stable isotope studies of Siberian and New World mammoths have shown there were also differences in climatic conditions on either side of the Bering land bridge, with Siberia being more uniformly cold and dry throughout the Late Pleistocene.[62] During the Younger Dryas age, woolly mammoths briefly expanded into north-east Europe, whereafter the mainland populations became extinct.[63] A 2008 genetic study showed that some of the woolly mammoths that entered North America through the Bering land bridge from Asia migrated back and replaced the Asian population shortly before the entire species went extinct.[64]

Relationship with humans[edit]

Woolly mammoth carved in ivory, discovered by Édouard Lartet in 1864

Modern humans coexisted with woolly mammoths during the Upper Palaeolithic period when they entered Europe from Africa between 30,000 and 40,000 years ago. Prior to this, Neanderthals had coexisted with mammoths during the Middle Palaeolithic. Woolly mammoths were very important to ice age humans, and human survival may have depended on the mammoth in some areas. Evidence for such coexistence was not recognised until the 19th century. William Buckland published his discovery of the Red Lady of Paviland skeleton in 1823, which was found in a cave alongside woolly mammoth bones, but he mistakenly denied that these were contemporaries. In 1864, Édouard Lartet found an engraving of a woolly mammoth on a piece of mammoth ivory in the Abri de la Madeleine cave in Dordogne, France. This 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.[65]

Cro-Magnon artists painting mammoths in Font-de-Gaume, by Charles R. Knight

The woolly mammoth is the third most depicted animal in ice age art, after horses and bisons, 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 "Portable art") made from ivory, antler, stone and bone. Cave paintings of woolly mammoths exist in several styles and sizes. The French Rouffignac cave has most depictions, 159, and some of the drawings are more than 2 metres (6.5 ft) in length. Other notable caves with mammoth depictions are the Chauvet Cave, Les Combarelles Cave, and Font-de-Gaume.[66] A depiction in the Cave of El Castillo may instead show Palaeoloxodon, the "straight-tusked elephant".[67]

"Portable art" can be more accurately dated than cave art since it is found in the same deposits as tools and other ice age artefacts. 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 Gönnersdorf in Germany. There does not seem to be a correlation between the number of mammoths depicted and the species that were most often hunted, since reindeer bones are the most frequently found animal remains at the site. Two spear throwers shaped as woolly mammoths have also been found in France.[66] Some portable mammoth depictions may not have been produced where they were discovered, but could have moved around by ancient trading.[67]

Exploitation[edit]

Reconstructed bone hut, based on finds in Mezhyrich

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 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.[68]

Woolly mammoth ivory was used to create art objects. Several Venus figurines, including the Venus of Brassempouy and the Venus of Lespugue, were made from this material. Weapons made from ivory, such as daggers, spears, and a boomerang, are also known. To be able to process the ivory, the large tusks had to be chopped, chiselled and split into smaller, more manageable pieces. Some ivory artefacts show that tusks had been straightened, and it is unknown how this was achieved.[69]

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.[70] A specimen from the Mousterian age of Italy shows evidence of spear hunting by Neanderthals.[71] The juvenile specimen nicknamed "Yuka" is the first frozen mammoth with evidence of human interaction. It shows evidence of having been killed by a large predator, and of having been scavenged by humans shortly after. Some of its bones had been removed, and were found nearby.[72] A site near the Yana River in Siberia has revealed several specimens with evidence of human hunting, but the finds were interpreted to show that the animals were not hunted intensively, but perhaps mainly when ivory was needed.[73]

Extinction[edit]

16,500 year old mammoth spear thrower from France

Most woolly mammoth populations disappeared during the late Pleistocene and early Holocene, alongside most of the Pleistocene megafauna, during the Quaternary extinction event.[74] Scientists are divided over whether hunting or climate change, which led to the disappearance of its habitat, was the main factor that contributed to the extinction of the woolly mammoth, but it is likely that it was a combination of the two. Whatever the cause, large mammals are generally more vulnerable than smaller ones due to their smaller population size and low reproduction rates. Different woolly mammoth populations did not die out simultaneously across their range, but gradually went extinct over time. The last mainland population existed in the Kyttyk Peninsula of Siberia 9,650 years ago.[75] A small population of woolly mammoths survived on St. Paul Island, Alaska, until 6,400 years ago.[25][76][77] The last known population remained on Wrangel Island in the Arctic Ocean until 4,000 years ago.[78][79][80]

Cast of the "Hebior Mammoth specimen", which bears tool/butcher marks

A 2008 study estimated that 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.[81][82] Woolly mammoths survived an even greater loss of habitat at the end of the Saale glaciation 125,000 years ago, and it is likely that humans hunted the remaining populations to extinction at the end of the last glacial period.[83][84] Studies of an 11,300–11,000 year old trackway in southwestern Canada showed that M. primigenius was in decline while coexisting with humans, since far fewer tracks of juveniles were identified than would be expected in a normal herd.[44]

A 2010 study hypothesises that the decline of the woolly mammoth could have increased temperatures by up to 0.2°C 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.[85]

Frozen specimens[edit]

Early 19th century interpretation of the "Adams mammoth" carcass prior to excavation

Woolly mammoth fossils have been found in many different types of deposits, including former rivers and lakes, and also in "Doggerland" in the North Sea, which was dry at times during the ice age. Such fossils are usually fragmentary and contain no soft tissue. Apart from frozen remains, the only soft tissue known is from a specimen that was preserved in a petroleum seep in Starunia, Poland. Frozen remains of woolly mammoths have been found in the northern parts of Siberia and Alaska, with far fewer finds in the latter. Such remains are mostly found above the Arctic Circle, in permafrost. It appears that soft tissue was less likely to be preserved between 30,000 and 15,000 years ago, perhaps because the climate was milder during that period. Most specimens have partially degraded prior to discovery, due to exposure or to being scavenged. This "natural mummification" required the animal to have been buried rapidly in liquid or semi-solids such as silt, mud and icy water, which then froze.[86] The presence of undigested food in the stomach and seed pods still in the mouth of many of the specimens suggests neither starvation nor exposure are likely. The maturity of this ingested vegetation places the time of death in autumn rather than in spring, when flowers would be expected.[87] 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.[88]

Illustration of the "Adams mammoth" skeleton with outward curving tusks, 1815

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.[89] While frozen woolly mammoth carcasses had been excavated by Europeans as early as 1728, the first fully documented specimen was discovered near the delta of the Lena River in 1799 by Ossip Schumachov, a Siberian hunter.[90] Schumachov let it thaw until he could retrieve the tusks for sale to the ivory trade. While in Yakutsk in 1806, Michael Friedrich Adams heard about the frozen mammoth. Upon arrival at the location, Adams discovered that wild animals had eaten most of the organs and flesh of the mammoth, including the trunk. He examined the carcass and realised what was left would still be the most complete mammoth recovered by that time. Adams recovered the entire skeleton, apart from the tusks, which Shumachov had already sold, and one foreleg, most of the skin, and nearly 18 kg (40 lb) of hair. During his return voyage he purchased a pair of tusks that he believed were the ones that Shumachov had sold. Adams brought it to the Zoological Museum of the Zoological Institute of the Russian Academy of Sciences, and the task of mounting the skeleton was given to Wilhelm Gottlieb Tilesius.[5] The Kunstkamera, the museum established by Peter the Great, contained the skeleton of an Indian elephant that could be used as reference.[91] 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.[92][93]

A third of this model is covered with the skin of the "Berezovka mammoth", Museum of Zoology, St. Petersburg

The 1901 excavation of the "Berezovka mammoth" is the best documented of the early finds. It was discovered by the 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 35–40 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.[87]

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 many more have been found. In most cases, the flesh showed signs of decay before its freezing and later desiccation.[94] Since 1860, Russian authorities have offered rewards of up to руб.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.[95]

"Dima", a frozen calf about seven months old

In 1977, the well-preserved carcass of a seven- to eight-month-old woolly mammoth calf named "Dima" was discovered. This carcass was recovered near a tributary of the Kolyma River in northeastern Siberia. This specimen weighed approximately 100 kg (220 lb) at death and was 104 cm (41 in) high and 115 cm (45 in) long. Radiocarbon dating determined that "Dima" died about 40,000 years ago. Its internal organs are similar to those of modern elephants, but its ears are only one-tenth the size of those of an African elephant of similar age. A less complete juvenile, nicknamed "Mascha", was found on the Yamal Peninsula 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.[96]

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 hairdryers to keep the hair and other soft tissues intact.[97][98]

Frozen calf nicknamed "Mascha"

In 2007, the carcass of a female calf nicknamed "Lyuba" was discovered near the Yuribei River, where it had been buried for 41,800 years.[50][99] By cutting a section through a molar and analysing its growth lines, they found that the animal had died at the age of one month.[57] The mummified calf weighed 50 kg (110 lb), was 85 cm (33 in) high and 130 cm (51 in) in length.[100][101] 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.[102] "Lyuba" is believed to have been suffocated by mud in a river that its herd was crossing.[50][103] After death, its body may have been colonised by bacteria that produce lactic acid, which "pickled" it, preserving the mammoth in a nearly pristine state.[50]

Skull and mandible of the frozen calf "Yuka"

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.[72] Another mammoth discovery was reported in October 2012, when it was excavated on the Taymyr Peninsula. It was dated to 30,000 years old. It was named "Zhenya" after the boy who found it.[104]

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.[105]

Recreating the species[edit]

The existence of preserved soft tissue remains and DNA of woolly mammoths has led to the idea that the species could be recreated by scientific means. Two methods have been proposed to achieve this. The first is cloning, which would involve removal of the DNA-containing nucleus of the egg cell of a female elephant, and replacement with a nucleus from woolly mammoth tissue. The cell would then be stimulated into dividing, and inserted back into a female elephant. The resulting calf would have the genes of the woolly mammoth, although its fetal environment would be different. To date, even the most intact mammoths have had little usable DNA because of their conditions of preservation. There is not enough to guide the production of an embryo.[106]

The second method involves artificially inseminating an elephant egg cell with sperm cells from a frozen woolly mammoth carcass. The resulting offspring would be an elephant–mammoth hybrid, and the process would have to be repeated so more hybrids could be used in breeding. After several generations of cross-breeding these hybrids, an almost pure woolly mammoth would be produced. The fact that sperm cells of modern mammals are potent for 15 years at most after deep-freezing is a hindrance to this method.[106] In one case, an Asian elephant and an African elephant produced a live calf named Motty, but it died of defects at less than two weeks old.[107]

In 2008, a Japanese team found usable DNA in the brains of mice that had been frozen for 16 years. They hope to use similar methods to find usable mammoth DNA.[108] In 2011, Japanese scientists announced plans to clone mammoths within six years.[109] In 2009, the Pyrenean Ibex (a subspecies of the Spanish ibex) was the first extinct animal to be cloned back to life; the clone lived for only seven minutes before dying of lung defects.[110] As the woolly mammoth genome has been mapped, a complete strand of DNA may be synthesised in the future.[111] Mammoth expert Adrian Lister questions the ethics of such recreation attempts. In addition to the technical problems, he notes that there is not much habitat left that would be suitable for woolly mammoths. Because the species was social and gregarious, creating a few specimens would not be ideal. He also notes that the time and resources required would be enormous, and that the scientific benefits would be unclear; these resources should instead be used to preserve extant elephant species which are endangered.[106]

Cultural significance[edit]

Peter III of Russia carved in mammoth ivory

The woolly mammoth has remained culturally significant long after its extinction. Indigenous peoples of Siberia had long found what are now known to be woolly mammoth remains, collecting their tusks for the ivory trade. Native Siberians believed woolly mammoth remains to be those of giant mole-like animals that lived underground and died when burrowing to the surface.[6] Woolly mammoth tusks had been articles of trade in Asia long before Europeans became acquainted with them. Güyük, the 13th-century Khan of the Mongols, is reputed to have sat on a throne made from mammoth ivory.[89] 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.[112]

Le Mammouth by Paul Jamin, 1885

When Russia occupied Siberia, the ivory trade grew and became a widely exported commodity, with huge amounts being excavated for this market. From the 19th century and onwards, woolly mammoth ivory became a highly prized commodity, used as raw material for many different 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 Lausanne Conference, but dealers have been known to label it as mammoth ivory to get it through customs. Mammoth ivory looks similar to elephant ivory, but the former is browner and the Schreger lines are coarser in texture.[113] In the 21st century, global warming has made access to Siberian tusks easier, since the permafrost thaws more quickly, exposing the mammoths embedded within it.[114]

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.[115]

Cryptozoology[edit]

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.[116] 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 went 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.[117]

Legends from several Native American tribes have also been interpreted by some as indicating folk memory of extinct elephants.[118][119][120] In the late 19th century, there were persistent rumours about surviving mammoths in Alaska.[116] 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 existence of any mammoth corpse; the story was a hoax.[121] Bengt Sjögren believed that the myth began when the American biologist Charles Haskins Townsend travelled 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.[116]

References[edit]

  1. ^ Donald K. Grayson, David J. Meltzer. 2002. Clovis Hunting and Large Mammal Extinction: A Critical Review of the Evidence. Journal of World Prehistory. December 2002, Volume 16, Issue 4, pp 313–359. http://link.springer.com/article/10.1023/A:1022912030020
  2. ^ a b Switek, B. (2010). Written in Stone: Evolution, the Fossil Record, and Our Place in Nature. Bellevue Literary Press. pp. 174–180. ISBN 978-1-934137-29-1. 
  3. ^ Sloane, H. (1727–1728). "An Account of Elephants Teeth and Bones Found under Ground". Philosophical Transactions 35 (399–406): 457–471. Bibcode:1727RSPT...35..457S. doi:10.1098/rstl.1727.0042. 
  4. ^ Sloane, H. (1727–1728). "Of Fossile Teeth and Bones of Elephants. Part the Second". Philosophical Transactions 35 (399–406): 497–514. Bibcode:1727RSPT...35..497S. doi:10.1098/rstl.1727.0048. 
  5. ^ a b The Academy of Natural Sciences (2007). "Woolly Mammoth (Mammuthus primigenius)". The Academy of Natural Sciences. Archived from the original on 27 September 2007. Retrieved 29 September 2007. 
  6. ^ a b Breyne, J. P.; s., T.; Wolochowicz, M. (1737). "A Letter from John Phil. Breyne, M. D. F. R. S. To Sir Hans Sloane, Bart. Pres. R. S. With Observations, and a Description of Some Mammoth's Bones Dug up in Siberia, Proving Them to Have Belonged to Elephants". Philosophical Transactions of the Royal Society of London 40 (445–451): 124. doi:10.1098/rstl.1737.0026.  edit
  7. ^ Cuvier, G. (1796). "Mémoire sur les épèces d'elephans tant vivantes que fossils, lu à la séance publique de l'Institut National le 15 germinal, an IV". Magasin encyclopédique, 2e anée (in French): 440–445. 
  8. ^ Reich, M.; Gehler, A. (2008). "Giants' Bones and Unicorn Horns Ice Age Elephants Offer 21st Century Insights". Collections - Wisdom, Insight, Innovation 8: 44–50. 
  9. ^ Brookes, J. (1828). A catalogue of the anatomical & zoological museum of Joshua Brookes 1. London: Richard Taylor. p. 73. 
  10. ^ Lister, 2007. p. 49
  11. ^ Simpson, J. (2009). "Word Stories: Mammoth." Oxford English Dictionary Online, Oxford University Press. Accessed 5 June 2009.
  12. ^ Lister, 2007. pp. 18–21
  13. ^ Shoshani, J.; Tassy, P. (2005). "Advances in proboscidean taxonomy & classification, anatomy & physiology, and ecology & behavior". Quaternary International. 126–128: 5. Bibcode:2005QuInt.126....5S. doi:10.1016/j.quaint.2004.04.011.  edit
  14. ^ Gross, L. (2006). "Reading the Evolutionary History of the Woolly Mammoth in Its Mitochondrial Genome". PLoS Biology 4 (3): e74. doi:10.1371/journal.pbio.0040074. PMC 1360100. PMID 20076539.  edit
  15. ^ Krause, J.; Dear, P. H.; Pollack, J. L.; Slatkin, M.; Spriggs, H.; Barnes, I.; Lister, A. M.; Ebersberger, I.; Pääbo, S.; Hofreiter, M. (2005). "Multiplex amplification of the mammoth mitochondrial genome and the evolution of Elephantidae". Nature 439 (7077): 724–727. doi:10.1038/nature04432. PMID 16362058.  edit
  16. ^ Rohland, N.; Reich, D.; Mallick, S.; Meyer, M.; Green, R. E.; Georgiadis, N. J.; Roca, A. L.; Hofreiter, M. (2010). "Genomic DNA Sequences from Mastodon and Woolly Mammoth Reveal Deep Speciation of Forest and Savanna Elephants". In Penny, David. PLoS Biology 8 (12): e1000564. doi:10.1371/journal.pbio.1000564. PMC 3006346. PMID 21203580.  edit
  17. ^ Will findings recreate the woolly mammoth?, Pittsburgh Post-Gazette, 20 November 2008
  18. ^ "Woolly-Mammoth Genome Sequenced". Science Daily. 20 November 2008. Retrieved 22 June 2010. 
  19. ^ Cappellini, E.; Jensen, L. J.; Szklarczyk, D.; Ginolhac, A. L.; Da Fonseca, R. A. R.; Stafford, T. W.; Holen, S. R.; Collins, M. J.; Orlando, L.; Willerslev, E.; Gilbert, M. T. P.; Olsen, J. V. (2012). "Proteomic analysis of a Pleistocene mammoth femur reveals more than one hundred ancient bone proteins". Journal of Proteome Research 11 (2): 917–926. doi:10.1021/pr200721u. PMID 22103443.  edit
  20. ^ a b c Lister, A. M.; Sher, A. V.; Van Essen, H.; Wei, G. (2005). "The pattern and process of mammoth evolution in Eurasia". Quaternary International. 126–128: 49. Bibcode:2005QuInt.126...49L. doi:10.1016/j.quaint.2004.04.014.  edit
  21. ^ Ferretti, M. P. (2003). "Structure and evolution of mammoth molar enamel". Acta Palaeontologica Polonica. 3 48: 383–396. 
  22. ^ Enk, J.; Devault, A.; Debruyne, R.; King, C. E.; Treangen, T.; O'Rourke, D.; Salzberg, S. L.; Fisher, D.; MacPhee, R.; Poinar, H. (2011). "Complete Columbian mammoth mitogenome suggests interbreeding with woolly mammoths". Genome Biology 12 (5): R51. doi:10.1186/gb-2011-12-5-r51. PMC 3219973. PMID 21627792.  edit
  23. ^ Foronova, I. V.; Zudin, A. N. (2001). Discreteness of evolution and variability in mammoth lineage: method for group study. Rome: The World of Elephants - Proceedings of the 1st International Congress, Rome, 2001. pp. 540–543. 
  24. ^ Vartanyan, S. L.; Garutt, V. E.; Sher, A. V. (1993). "Holocene dwarf mammoths from Wrangel Island in the Siberian Arctic". Nature 362 (6418): 337. doi:10.1038/362337a0.  edit
  25. ^ a b Dale Guthrie, R. (2004). "Radiocarbon evidence of mid-Holocene mammoths stranded on an Alaskan Bering Sea island". Nature 429 (6993): 746–749. doi:10.1038/nature02612. PMID 15201907.  edit
  26. ^ Nystrom, V.; Dalen, L.; Vartanyan, S.; Liden, K.; Ryman, N.; Angerbjorn, A. (2010). "Temporal genetic change in the last remaining population of woolly mammoth". Proceedings of the Royal Society B: Biological Sciences 277 (1692): 2331. doi:10.1098/rspb.2010.0301.  edit
  27. ^ Lister, 2007. pp. 82–83
  28. ^ Vartanyan, S. L.; Arslanov, K. A.; Karhu, J. A.; Possnert, G. R.; Sulerzhitsky, L. D. (2008). "Collection of radiocarbon dates on the mammoths (Mammuthus primigenius) and other genera of Wrangel Island, northeast Siberia, Russia". Quaternary Research 70: 51. doi:10.1016/j.yqres.2008.03.005.  edit
  29. ^ Den Ouden, N.; Reumer, J. W. F.; Van Den Hoek Ostende, L. W. (2012). "Did mammoth end up a lilliput? Temporal body size trends in Late Pleistocene Mammoths, Mammuthus primigenius (Blumenbach, 1799) inferred from dental data". Quaternary International 255: 53. Bibcode:2012QuInt.255...53D. doi:10.1016/j.quaint.2011.07.038.  edit
  30. ^ a b c d Lister, 2007. pp. 82–87
  31. ^ Norwood, Lindsay (n.d.) Loxodonta Africana, African bush elephant. Retrieved from http://animaldiversity.ummz.umich.edu/accounts/Loxodonta_africana/
  32. ^ Lister, 2007. pp. 174–175
  33. ^ Lister, 2007. pp. 83–84
  34. ^ Valente, A. (1983). "Hair structure of the Woolly mammoth, Mammuthus primigenius and the modern elephants, Elephas maximus and Loxodonta africana". Journal of Zoology 199 (2): 271–274. doi:10.1111/j.1469-7998.1983.tb02095.x.  edit
  35. ^ Repin, V. E.; Taranov, O. S.; Ryabchikova, E. I.; Tikhonov, A. N.; Pugachev, V. G. (2004). "Sebaceous Glands of the Woolly Mammoth, Mammothus primigenius Blum.: Histological Evidence". Doklady Biological Sciences 398: 382–384. doi:10.1023/B:DOBS.0000046662.43270.66. PMID 15587793.  edit
  36. ^ Rompler, H.; Rohland, N.; Lalueza-Fox, C.; Willerslev, E.; Kuznetsova, T.; Rabeder, G.; Bertranpetit, J.; Schöneberg, T.; Hofreiter, M. (2006). "Nuclear Gene Indicates Coat-Color Polymorphism in Mammoths". Science 313 (5783): 62. doi:10.1126/science.1128994. PMID 16825562.  edit
  37. ^ Workman, C.; Dalen, L.; Vartanyan, S.; Shapiro, B.; Kosintsev, P.; Sher, A.; Gotherstrom, A.; Barnes, I. (2011). "Population-level genotyping of coat colour polymorphism in woolly mammoth (Mammuthus primigenius)". Quaternary Science Reviews 30 (17–18): 2304. Bibcode:2011QSRv...30.2304W. doi:10.1016/j.quascirev.2010.08.020.  edit
  38. ^ Lister, 2007. pp. 94–95
  39. ^ Lister, 2007. pp. 92–93
  40. ^ Lister, 2007. pp. 108–109
  41. ^ Lister, 2007. pp. 95–105
  42. ^ Campbell, K. L.; Roberts, J. E. E.; Watson, L. N.; Stetefeld, J. R.; Sloan, A. M.; Signore, A. V.; Howatt, J. W.; Tame, J. R. H.; Rohland, N.; Shen, T. J.; Austin, J. J.; Hofreiter, M.; Ho, C.; Weber, R. E.; Cooper, A. (2010). "Substitutions in woolly mammoth hemoglobin confer biochemical properties adaptive for cold tolerance". Nature Genetics 42 (6): 536–540. doi:10.1038/ng.574. PMID 20436470.  edit
  43. ^ Lister, 2007. pp. 62–63
  44. ^ a b McNeil, P.; Hills, L.; Kooyman, B.; Tolman, S. (2005). "Mammoth tracks indicate a declining Late Pleistocene population in southwestern Alberta, Canada". Quaternary Science Reviews 24 (10–11): 1253. Bibcode:2005QSRv...24.1253M. doi:10.1016/j.quascirev.2004.08.019.  edit
  45. ^ Lister, 2007. pp. 108–111
  46. ^ Lister, 2007. p. 87
  47. ^ Lister, 2007. pp. 88–91
  48. ^ Bocherens, H.; Fizet, M.; Mariotti, A.; Gangloff, R. A.; Burns, J. A. (1994). "Contribution of isotopic biogeochemistry (13C,15N,18O) to the paleoecology of mammoths (Mammuthus primigenius)". Historical Biology 7 (3): 187. doi:10.1080/10292389409380453.  edit
  49. ^ Van Geel, B.; Fisher, D. C.; Rountrey, A. N.; Van Arkel, J.; Duivenvoorden, J. F.; Nieman, A. M.; Van Reenen, G. B. A.; Tikhonov, A. N.; Buigues, B.; Gravendeel, B. (2011). "Palaeo-environmental and dietary analysis of intestinal contents of a mammoth calf (Yamal Peninsula, northwest Siberia)". Quaternary Science Reviews 30 (27–28): 3935. Bibcode:2011QSRv...30.3935V. doi:10.1016/j.quascirev.2011.10.009.  edit
  50. ^ a b c d Fisher, D. C.; Tikhonov, A. N.; Kosintsev, P. A.; Rountrey, A. N.; Buigues, B.; Van Der Plicht, J. (2012). "Anatomy, death, and preservation of a woolly mammoth (Mammuthus primigenius) calf, Yamal Peninsula, northwest Siberia". Quaternary International 255: 94. Bibcode:2012QuInt.255...94F. doi:10.1016/j.quaint.2011.05.040.  edit
  51. ^ Metcalfe, J. Z.; Longstaffe, F. J.; Zazula, G. D. (2010). "Nursing, weaning, and tooth development in woolly mammoths from Old Crow, Yukon, Canada: Implications for Pleistocene extinctions". Palaeogeography, Palaeoclimatology, Palaeoecology 298 (3–4): 257. doi:10.1016/j.palaeo.2010.09.032.  edit
  52. ^ Lister, 2007. pp. 92–95
  53. ^ Lister, 2007. pp. 83–107.
  54. ^ Mol, D.; Shoshani, J.; Thikhonov, A.; van Geel, B.; Sano, S.; Lasarev, P.; Agenbroad, L. (2006). "The Yukagir mammoth: brief history, 14c dates, individual age, gender, size, physical and environmental conditions and storage". Scientific Annals, School of Geology Aristotle University of Thessaloniki 98: 299–314 
  55. ^ Lister, 2007. pp. 102–103
  56. ^ Lister, 2007. pp. 104–105
  57. ^ a b Rountrey, A. N.; Fisher, D. C.; Tikhonov, A. N.; Kosintsev, P. A.; Lazarev, P. A.; Boeskorov, G.; Buigues, B. (2012). "Early tooth development, gestation, and season of birth in mammoths". Quaternary International 255: 196. Bibcode:2012QuInt.255..196R. doi:10.1016/j.quaint.2011.06.006.  edit
  58. ^ Lister, 2007. pp. 88–89
  59. ^ Takahashi, K.; Wei, G.; Uno, H.; Yoneda, M.; Jin, C.; Sun, C.; Zhang, S.; Zhong, B. (2007). "AMS 14C chronology of the world's southernmost woolly mammoth (Mammuthus primigenius Blum.)". Quaternary Science Reviews 26 (7–8): 954. Bibcode:2007QSRv...26..954T. doi:10.1016/j.quascirev.2006.12.001.  edit
  60. ^ Álvarez-Lao, D. J.; García, N. (2012). "Comparative revision of the Iberian woolly mammoth (Mammuthus primigenius) record into a European context". Quaternary Science Reviews 32: 64. doi:10.1016/j.quascirev.2011.11.004.  edit
  61. ^ Gilbert, M. T. P.; Drautz, D. I.; Lesk, A. M.; Ho, S. Y. W.; Qi, J.; Ratan, A.; Hsu, C. -H.; Sher, A.; Dalen, L.; Gotherstrom, A.; Tomsho, L. P.; Rendulic, S.; Packard, M.; Campos, P. F.; Kuznetsova, T. V.; Shidlovskiy, F.; Tikhonov, A.; Willerslev, E.; Iacumin, P.; Buigues, B.; Ericson, P. G. P.; Germonpre, M.; Kosintsev, P.; Nikolaev, V.; Nowak-Kemp, M.; Knight, J. R.; Irzyk, G. P.; Perbost, C. S.; Fredrikson, K. M.; Harkins, T. T. (2008). "Intraspecific phylogenetic analysis of Siberian woolly mammoths using complete mitochondrial genomes". Proceedings of the National Academy of Sciences 105 (24): 8327. doi:10.1073/pnas.0802315105.  edit
  62. ^ Szpak, P.; Gröcke, D. R.; Debruyne, R.; MacPhee, R. D. E.; Guthrie, R. D.; Froese, D.; Zazula, G. D.; Patterson, W. P.; Poinar, H. N. (2010). "Regional differences in bone collagen δ13C and δ15N of Pleistocene mammoths: Implications for paleoecology of the mammoth steppe". Palaeogeography, Palaeoclimatology, Palaeoecology 286: 88. doi:10.1016/j.palaeo.2009.12.009.  edit
  63. ^ Stuart, A. J. (2005). "The extinction of woolly mammoth (Mammuthus primigenius) and straight-tusked elephant (Palaeoloxodon antiquus) in Europe". Quaternary International. 126–128: 171–177. Bibcode:2005QuInt.126..171S. doi:10.1016/j.quaint.2004.04.021.  edit
  64. ^ Debruyne, R.; Chu, G.; King, C. E.; Bos, K.; Kuch, M.; Schwarz, C.; Szpak, P.; Gröcke, D. R.; Matheus, P.; Zazula, G.; Guthrie, D.; Froese, D.; Buigues, B.; De Marliave, C.; Flemming, C.; Poinar, D.; Fisher, D.; Southon, J.; Tikhonov, A. N.; MacPhee, R. D. E.; Poinar, H. N. (2008). "Out of America: Ancient DNA Evidence for a New World Origin of Late Quaternary Woolly Mammoths". Current Biology 18 (17): 1320–1326. doi:10.1016/j.cub.2008.07.061. PMID 18771918.  edit
  65. ^ Lister, 2007. pp. 116–117
  66. ^ a b Lister, 2007. pp. 118–125
  67. ^ a b Braun, I. M.; Palombo, M. R. (2012). "Mammuthus primigenius in the cave and portable art: An overview with a short account on the elephant fossil record in Southern Europe during the last glacial". Quaternary International. 276-277: 61. doi:10.1016/j.quaint.2012.07.010.  edit
  68. ^ Lister, 2007. pp. 128–132
  69. ^ Lister, 2007. pp. 131–137
  70. ^ Lister, 2007. pp. 151–155
  71. ^ Mussi, M.; Villa, P. (2008). "Single carcass of Mammuthus primigenius with lithic artifacts in the Upper Pleistocene of northern Italy". Journal of Archaeological Science 35 (9): 2606. doi:10.1016/j.jas.2008.04.014.  edit
  72. ^ a b Aviss, B. (4 April 2012). "Woolly mammoth carcass may have been cut into by humans". BBC. Retrieved 9 April 2012. 
  73. ^ Nikolskiy, P.; Pitulko, V. (2013). "Evidence from the Yana Palaeolithic site, Arctic Siberia, yields clues to the riddle of mammoth hunting". Journal of Archaeological Science 40 (12): 4189. doi:10.1016/j.jas.2013.05.020.  edit
  74. ^ Stuart, A. J.; Sulerzhitsky, L. D.; Orlova, L. A.; Kuzmin, Y. V.; Lister, A. M. (2002). "The latest woolly mammoths (Mammuthus primigenius Blumenbach) in Europe and Asia: A review of the current evidence". Quaternary Science Reviews 21 (14–15): 1559. doi:10.1016/S0277-3791(02)00026-4.  edit
  75. ^ Lister, 2007. pp. 146–148
  76. ^ Yesner, D. R.; Veltre, D. W.; Crossen, K. J.; Graham, R. W. "5,700-year-old Mammoth Remains from Qagnax Cave, Pribilof Islands, Alaska". Second World of Elephants Congress, (Hot Springs: Mammoth Site, 2005): 200–203. 
  77. ^ Crossen, K. S. (2005). "5,700-Year-Old Mammoth Remains from the Pribilof Islands, Alaska: Last Outpost of North America Megafauna". Geological Society of America 37: 463. 
  78. ^ Stuart, A. J.; Kosintsev, P. A.; Higham, T. F. G.; Lister, A. M. (2004). "Pleistocene to Holocene extinction dynamics in giant deer and woolly mammoth". Nature 431 (7009): 684–689. doi:10.1038/nature02890. PMID 15470427.  edit
  79. ^ Vartanyan, S. L.; et al. (1995). "Radiocarbon Dating Evidence for Mammoths on Wrangel Island, Arctic Ocean, until 2000 BC". Radiocarbon 37 (1): 1–6. ISSN 0033-8222. 
  80. ^ Nyström, V.; Humphrey, J.; Skoglund, P.; McKeown, N. J.; Vartanyan, S.; Shaw, P. W.; Lidén, K.; Jakobsson, M.; Barnes, I. A. N.; Angerbjörn, A.; Lister, A.; Dalén, L. (2012). "Microsatellite genotyping reveals end-Pleistocene decline in mammoth autosomal genetic variation". Molecular Ecology 21 (14): 3391–3402. doi:10.1111/j.1365-294X.2012.05525.x. PMID 22443459.  edit
  81. ^ Nogués-Bravo, D.; Rodríguez, J. S.; Hortal, J. N.; Batra, P.; Araújo, M. B. (2008). "Climate Change, Humans, and the Extinction of the Woolly Mammoth". In Barnosky, Anthony. PLoS Biology 6 (4): e79. doi:10.1371/journal.pbio.0060079. PMC 2276529. PMID 18384234.  edit
  82. ^ Sedwick, C. (2008). "What Killed the Woolly Mammoth?". PLoS Biology 6 (4): e99. doi:10.1371/journal.pbio.0060099. PMC 2276526. PMID 20076709.  edit
  83. ^ Martin, P. S (2005). Twilight of the Mammoths: Ice Age Extinctions and the Rewilding of America. University of California Press. pp. 165–173. ISBN 0-520-23141-4. 
  84. ^ Burney, D.; Flannery, T. (2005). "Fifty millennia of catastrophic extinctions after human contact". Trends in Ecology & Evolution 20 (7): 395–401. doi:10.1016/j.tree.2005.04.022. PMID 16701402.  edit
  85. ^ Doughty, C. E.; Wolf, A.; Field, C. B. (2010). "Biophysical feedbacks between the Pleistocene megafauna extinction and climate: the first human-induced global warming?". Geophysical Research Letters 37 (15). Bibcode:2010GeoRL..3715703D. doi:10.1029/2010GL043985.  edit
  86. ^ Lister, 2007. pp. 50–51
  87. ^ a b Pfizenmayer, E. W. (1939). Siberian Man and Mammoth. London: Blackie and Son. pp. 46–61. 
  88. ^ Vereshchagin, N. K. (2009). "The mammoth "cemeteries" of north-east Siberia". Polar Record 17 (106): 3. doi:10.1017/S0032247400031296.  edit
  89. ^ a b Tolmachoff, I. P. (1929). "The carcasses of the mammoth and rhinoceros found in the frozen ground of Siberia". Transactions of the American Philosophical Society (American Philosophical Society) 23 (1): 11–23. doi:10.2307/1005437. JSTOR 1005437.  edit
  90. ^ Adams, M. (1808). "Some Account of a Journey to the Frozen-Sea, and of the Discovery of the Remains of a Mammoth". The Philadelphia Medical and Physical Journal 3: 120–137. 
  91. ^ Tilesio, W. G. (1815). "De skeleto mammonteo Sibirico ad maris glacialis littora anno 1807 effosso, cui praemissae Elephantini generis specierum distinctiones". Mémoires de l'Académie Impériale des Sciences de St. Pétersbourg (in Latin) 5: 406–514. 
  92. ^ Cohen, C. (2002). The Fate of the Mammoth: Fossils, Myth, and History. University of Chicago Press. p. 113. ISBN 978-0-226-11292-3. 
  93. ^ Pfitzenmayer, E. (1907). "A Contribution to the Morphology of the Mammoth, Elephas Primigenius Blumenbach; With an Explanation of My Attempt at a Restoration". Annual report of the Board of Regents of the Smithsonian Institution: 326–334. 
  94. ^ Farrand, W. R. (1961). "Frozen Mammoths and Modern Geology: The death of the giants can be explained as a hazard of tundra life, without evoking catastrophic events". Science 133 (3455): 729–735. Bibcode:1961Sci...133..729F. doi:10.1126/science.133.3455.729. PMID 17777646.  edit
  95. ^ Lister, 2007. p. 59
  96. ^ Lister, 2007. pp. 57–58
  97. ^ Mol, D. et al. (2001). The Jarkov Mammoth: 20,000-Year-Old carcass of a Siberian woolly mammoth Mammuthus primigenius (Blumenbach, 1799). The World of Elephants, Proceedings of the 1st International Congress ( 16–20 October 2001, Rome): 305–309. Full text pdf[dead link]
  98. ^ Debruyne, R. G.; Barriel, V. R.; Tassy, P. (2003). "Mitochondrial cytochrome b of the Lyakhov mammoth (Proboscidea, Mammalia): New data and phylogenetic analyses of Elephantidae". Molecular Phylogenetics and Evolution 26 (3): 421–434. doi:10.1016/S1055-7903(02)00292-0. PMID 12644401.  edit
  99. ^ Kosintsev, P. A.; Lapteva, E. G.; Trofimova, S. S.; Zanina, O. G.; Tikhonov, A. N.; Van Der Plicht, J. (2012). "Environmental reconstruction inferred from the intestinal contents of the Yamal baby mammoth Lyuba (Mammuthus primigenius Blumenbach, 1799)". Quaternary International 255: 231. Bibcode:2012QuInt.255..231K. doi:10.1016/j.quaint.2011.03.027.  edit
  100. ^ Rincon, P. (10 July 2007). "Baby mammoth discovery unveiled". news.bbc.co.uk (BBC News). Retrieved 13 July 2007. 
  101. ^ Solovyov, D. (11 July 2007). "Baby mammoth find promises breakthrough". reuters.com (Reuters). Retrieved 13 July 2007. 
  102. ^ Smith, O. (21 April 2009). "Baby mammoth Lyuba, pristinely preserved, offers scientists rare look into mysteries of Ice Age". Daily News (New York). 
  103. ^ Fisher, Daniel C. (2014). "X-ray computed tomography of two mammoth calf mummies". Journal of Paleontology 88 (4): 664–675. doi:10.1666/13-092.  edit
  104. ^ "Child finds 30,000 year old mammoth in North Russia". Russia Today. 4 October 2012. Retrieved 4 October 2012. 
  105. ^ Wong, K. (2013). "Can a mammoth carcass really preserve flowing blood and possibly live cells?". Nature. doi:10.1038/nature.2013.13103.  edit
  106. ^ a b c Lister, 2007. pp. 42–43
  107. ^ Stone, R. (1999). "Cloning the Woolly Mammoth". Discover Magazine. 
  108. ^ "Cloned Mammoths Made More Likely by Frozen Mice". FOX News. 5 November 2008. Retrieved 4 November 2008. 
  109. ^ Lendon, B. (2011). "Scientists trying to clone, resurrect extinct mammoth". CNN. Retrieved 22 May 2013. 
  110. ^ "Extinct ibex is resurrected by cloning". Telegraph Online. 2009. Retrieved 9 April 2012. 
  111. ^ "Mammoth Genome Project". Pennsylvania State University. Retrieved 18 March 2013. 
  112. ^ Lister, 2007. p. 137
  113. ^ Lister, 2007. pp. 137–139
  114. ^ Of Mammoths and Men April 2013 National Geographic (magazine)
  115. ^ Lister, 2007. p. 54
  116. ^ a b c Sjögren, B. (1962). Farliga djur och djur som inte finns (in Swedish). Prisma. p. 168. 
  117. ^ Lister, 2007. p. 55
  118. ^ Strong, W. D. (1934). "North American Indian traditions suggesting a knowledge of the mammoth". American Anthropologist 36: 81–88. doi:10.1525/aa.1934.36.1.02a00060.  edit
  119. ^ Lankford, G. E. (1980). "Pleistocene Animals in Folk Memory". The Journal of American Folklore 93 (369): 293–304. doi:10.2307/540573. JSTOR 540573.  {subscription required}
  120. ^ Mayor, A. (2005). Fossil Legends of the First Americans. Princeton: Princeton University Press. p. 97. ISBN 0-691-11345-9. 
  121. ^ Murray, M. (1960). "Henry Tukeman: Mammoth's Roar was Heard All The Way to the Smithsonian". Tacoma Public Library. Retrieved 17 January 2008. 

Bibliography[edit]