Mammoths belong to the order Proboscidea, which also include mastodons and elephants. Species in this order can be immense in size, and the larger species have massive column-like limbs, a long and flexible trunk, and well-developed tusks.
Mammoths lived during the Pleistocene (about 1.8 million to ~10,000 years ago), when the most recent ice ages took place. Mammoths were adapted to live in these colder climates and lived in open prairies and the tundra and taiga regions of the world.
Mammoths were herbivores, which means they only ate plants. What kind of plants mammoths ate depended on the species of mammoth and what habitat they lived in. Some mammoths only ate grasses, but other mammoths could also eat shrubs, leaves, and bark. The biggest predators of mammoths were humans.
Mammoths went extinct about 10,000 years ago.
The first mammoths appeared in Africa during the early Pleistocene, about 2 million years ago. Soon after (about 1.8 to 1.5 million years ago) they spread to Europe, Asia and North America. It is thought that mammoths crossed the Bering Strait to reach North America.
They had a very wide geographic range and their fossils are found on every continent except Australia and South America. Their range was much wider than their close cousins, African elephants (Loxodonta) and Asian elephants (Elephas).
Mammoths belong to the order Proboscidea, which also include mastodons and modern African and Asian elephants. Species in this order can be immense in size, and the larger species have massive column-like limbs, a long and flexible trunk, and well-developed tusks.
Mammoth teeth were made up of molars, and these molars are made of a series of vertical flat plates. Each half of the jaw contained 6 molars. The molar plates were made of ridges of compressed enamel which covered cementum. (Human teeth also have enamel covering cementum.) These strong molars looked like washboards, and did not wear easily. They were used to shear vegetation like scissors. Mammoth skulls were high and dome-like. The lower jaw was large with a well-defined chin. The nasal bones were shortened to make room for the long trunk, and the long curved tusks projected well beyond the nasal bones.
Mammoths were similar in shape and size to modern elephants, but were covered in long, coarse hair. The hair was black or reddish-brown in color and could be up to 50cm long. Some species of mammoths also had an undercoat of wooly hair about 2.5 cm thick.
The size of a mammoth depended on the species. From foot to shoulder, they could have ranged from 2.4m to 4.0m in height.
Mammoths lived during the Pleistocene (about 1.8 million to ~10,000 years ago), when the most recent ice ages took place. During the Pleistocene, the Earth went through a cooling period and glaciers covered large areas of land. There would also be short warming periods when glaciers retreated. Most ice ages had cycles of long cold periods and short warming periods. Mammoths were adapted to live in these colder climates and lived in open prairies and the tundra and taiga regions of the world.
Mammoths were herbivores, which means they only ate plants. What kind of plants mammoths ate depended on the species of mammoth and what habitat they lived in. Some mammoths only ate grasses but other mammoths could also eat shrubs, leaves, and bark. Mammoths used their specialized teeth to grind and eat their food. Their tusks could have been used to eat food by scraping ice and snow off vegetation.
Similar to their elephant cousins, it is thought that Mammoths spent most of their time eating. A 6-ton woolly mammoth would need to eat about 90kg of food a day!
About 10,000 years ago mammoths went extinct. Mammoths were specialized to live in cold climates and open woodland and grassland habitats. Approximately 10,000 years ago the globe started to warm up and the last ice age ended. Open woodlands and grasslands changed to forests, and the mammoth’s habitats and food supply changed. It is thought that they were not able to adapt to the change in climate and habitat and thus became extinct.
However, many scientists think that the climate shift was not enough to cause the extinction of mammoths. Ice ages naturally had cycles of long cold periods and short warming periods, and the mammoths survived previous warming periods of the Pleistocene (about 1.8 million to ~10,000 years ago). One difference during the warming period at the end of the Pleistocene was the presence of humans. 10,000 years ago, humans were found in most areas of the globe and hunted mammoths. It is thought that increased hunting pressure from humans combined with the change in climate caused the extinction of mammoths. However, scientists are still debating and researching this theory.
Mammoths had few predators because of their large size and protective social groups. It is likely that large carnivores of the time (like Smilodon) carried off very young or very old members of a mammoth herd.
The biggest predators of mammoths were humans. Humans lived in direct contact with mammoths about 12,000 years ago. From excavation of the areas where these human hunters lived (called Clovis sites) and from cave paintings, scientists know that humans hunted and killed mammoths.
Life History and Behavior
Evidence from fossil sites suggests that mammoth behavior was similar to modern elephant behavior. Mammoths most likely lived in social groups that protected one another. Family groups would include females and juveniles. Juvenile males and young-adult males (aged 12-30) would leave the family group for 16 to 20 years and live by themselves or in groups with other males.
The life span of a mammoth would vary depending on the species and the environment in which the mammoth lived. A juvenile mammoth (a mammoth before it reached full maturity) could range from 10 to 19 years old. Mammoths reached adulthood at about 20 years of age and could live to be 60 to 80 years old.
Evolution and Systematics
Systematics and Taxonomy
It is important to note that mammoths are not modern elephants ancestors. Mammoths and modern elephants evolved from a common ancestor and lived on the earth together for about 4 million years.
Molecular Biology and Genetics
Statistics of barcoding coverage
|Specimen Records:||20||Public Records:||20|
|Specimens with Sequences:||20||Public Species:||1|
|Specimens with Barcodes:||20||Public BINs:||1|
|Species With Barcodes:||1|
A mammoth is any species of the extinct genus Mammuthus. These proboscideans are members of Elephantidae, the family of elephants and mammoths, and close relatives of modern elephants. They were often equipped with long curved tusks and, in northern species, a covering of long hair. They lived from the Pliocene epoch from around 4.8 million to 4,500 years ago. The word mammoth comes from the Russian мамонт mamont, probably in turn from the Vogul (Mansi) language, mang ont, meaning "earth horn".
Like their modern relative the elephant (Asian or African), mammoths were quite large; in English the noun "mammoth" has become an adjective meaning "large" or "massive". The largest known species, Songhua River mammoth (Mammuthus sungari) , reached heights of at least 5 metres (16 feet) at the shoulder. Mammoths would probably normally weigh in the region of 6 to 8 tons, but exceptionally large males may have exceeded 12 tons. However, most species of mammoth were only about as large as a modern Asian elephant. Fossils of species of dwarf mammoth have been found on the Californian Channel Islands (Mammuthus exilis) and the Mediterranean island of Sardinia (Mammuthus lamarmorae). There was also a race of dwarf woolly mammoths on Wrangel Island, north of Siberia, within the Arctic Circle.
Based on studies of their close relatives the modern elephants, mammoths probably had a gestation period of 22 months, resulting in a single calf being born. Their social structure was probably the same as that of African and Asian elephants, with females living in herds headed by a matriarch, whilst bulls lived solitary lives or formed loose groups after sexual maturity.
Well-preserved specimens and prospects for cloning
In May 2007, the carcass of a one-month-old female woolly mammoth calf was discovered in a layer of permafrost near the Yuribei River in Russia, where it had been buried for approximately 10,000 years. Alexei Tikhonov, the Russian Academy of Science's Zoological Institute's deputy director, has dismissed the prospect of cloning the animal, as the whole cells required for cloning would have burst under the freezing conditions. Nonetheless, DNA is expected to be well-enough preserved to be useful for research on mammoth phylogeny and perhaps physiology. However, Dr. Sayaka Wakayama from the RIKEN Center for Developmental Biology in Kobe, Japan, believes that a technique she has used to clone mice from specimens frozen for sixteen years could be used successfully on recovered mammoth tissue: she cites that in her experiments the dead mice had been frozen to -20°C under simulated natural conditions, without using the usual preservative chemicals.
Researchers at Penn State University have sequenced about 85% of the gene map of the woolly mammoth, using DNA taken from hair samples collected from a selection of specimens, advancing the possibility of bringing the woolly mammoth back to life by inserting mammoth DNA sequences into the genome of the modern-day elephant, transferring it into an egg cell and, in turn, into the uterus of an elephant as a variant of interspecific pregnancy. Although the samples were washed with bleach to remove possible contamination by bacteria or fungi, some DNA bases identified may be from the contaminating organisms and these have yet to be distinguished. To this end, scientists at the Broad Institute are currently generating a comparison with the genome of the African elephant. The information cannot be used to synthesize mammoth DNA, but Dr. Stephan Schuster, leader of the project, notes that the mammoth’s genes differ at only some 400,000 sites from the genome of the African elephant and it would be possible (though not with presently available technology) to modify an elephant cell at these sites to make it resemble one bearing a mammoth's genome, and implant it into a surrogate elephant mother.
In January 2011, it was reported by Yomiuri Shimbun that a team of scientists headed by Akira Iritani of Kyoto University had built upon research by Dr. Wakayama mentioned above, saying they will extract DNA from a mammoth carcass that had been preserved in a Russian laboratory and insert it into the egg cells of an African elephant in hopes of producing a mammoth embryo. The researchers said they hoped to produce a baby mammoth within six years.
Availability of remains
There is an estimate of 150 million mammoth remains in Russia's Siberian permafrost, which covers a vast sparsely inhabited area. Some of the remains are frozen complete, others in pieces of bone, tusk, tissue and wool, from less than a metre (3.3 ft) to 1 km (3300 ft) below ground.
The woolly mammoth was the last species of the genus. Most populations of the woolly mammoth in North America and Eurasia, as well all the Columbian mammoths in North America, died out around the time of the last glacial retreat, as part of a mass extinction of megafauna in northern Eurasia and the Americas. Until recently, it was generally assumed that the last woolly mammoths vanished from Europe and southern Siberia about 10,000 BC, but new findings show that some were still present there about 8000 BC. Only slightly later, the woolly mammoths also disappeared from continental northern Siberia. A small population survived on St. Paul Island, Alaska, up until 3,750 BC, and the small mammoths of Wrangel Island survived until 1,650 BC.
A definitive explanation for their mass extinction is yet to be agreed upon. The warming trend (Holocene) that occurred 12,000 years ago, accompanied by a glacial retreat and rising sea levels, has been suggested as a contributing factor. Forests replaced open woodlands and grasslands across the continent. The available habitat may have been reduced for some megafaunal species, such as the mammoth. However, such climate changes were nothing new; numerous very similar warming episodes had occurred previously within the ice age of the last several million years without producing comparable megafaunal extinctions, so climate alone is unlikely to have played a decisive role. The spread of advanced human hunters through northern Eurasia and the Americas around the time of the extinctions was a new development, and thus probably contributed significantly.
Whether the general mammoth population died out for climatic reasons or due to overhunting by humans is controversial. Another theory suggests that mammoths may have fallen victim to an infectious disease. A combination of climate change and hunting by humans has been suggested[by whom?] as the most likely explanation for their extinction.
Data derived from studies done on living elephants suggest human hunting was likely a strong contributing factor in the mammoth's final extinction. Homo erectus is known to have consumed mammoth meat as early as 1.8 million years ago.
However, the American Institute of Biological Sciences also notes bones of dead elephants, left on the ground and subsequently trampled by other elephants, tend to bear marks resembling butchery marks, which have previously been misinterpreted as such by archaeologists.
The survival of the dwarf mammoths on Russia's Wrangel Island was due to the island's very remote location and lack of inhabitants in the early Holocene period. The European discovery of the island (by American whalers) did not occur until the 1820s. A similar dwarfing occurred with the pygmy mammoth on the outer Channel Islands of California, but at an earlier period. Those animals were very likely killed by early Paleo-Native Americans, and habitat loss caused by a rising sea level that split Santa Rosae into the outer Channel Islands.
Recent research indicates that mammoths survived on the American mainland until 10,000 years ago. This conclusion is from research, by James Haile and Eske Willerslev of the University of Copenhagen, of sediments found in central Alaska, and reported in the Proceedings of the National Academy of Sciences.
Yet another theory explaining the extinction of all the North American megafuana as well as the Clovis culture is the "Clovis comet," a hypothesized asteroid or comet airburst or impact on the glacial ice-sheet event which caused effects similar to but less severe in scale to the larger global impact event theorized as responsible for the extinction of the dinosaurs.
- La Brea Tar Pits - cluster of tar pits located in Los Angeles, California, USA
- Pleistocene Park
- Capelli, Cristian; MacPhee, Ross D.E.; Roca, Alfred L.; Brisighelli, Francesca; Georgiadis, Nicholase; O'Brien, Stephen J.; Greenwood, Alex D. (2006): A nuclear DNA phylogeny of the woolly mammoth (Mammuthus primigenius). Molecular Phylogenetics and Evolution 40 (2) 620–627. doi:10.1016/j.ympev.2006.03.015 (HTML abstract). Supplemental data available to subscribers.
- Levy, Sharon (2006): Clashing with Titans. BioScience 56(4): 292-298. DOI:10.1641/0006-3568(2006)56[292:CWT]2.0.CO;2 PDF fulltext
- Lister, Adrian & Bahn, Paul (1994): Mammoths. MacMillan, London. ISBN 0-02-572985-3
- Martin, Paul S. (2005): Twilight of the mammoths: Ice Age extinctions and the rewilding of America. University of California Press, Berkeley. ISBN 0-520-23141-4
- Mercer, H.C. (1885): The Lenape Stone or The Indian and the Mammoth. DjVu fulltext PDF fulltext
- Stone, Richard (2001): Mammoth: The resurrection of an Ice Age giant. Fourth Estate, London. ISBN 1-84115-518-7
- ^ "Woolly Mammoth (Mammuthus primigenius)". Academy of Natural Sciences. http://www.ansp.org/museum/jefferson/otherFossils/mammuthus.php#top. Retrieved 2007-07-20.
- ^ a b Schirber, Michael. "Surviving Extinction: Where Woolly Mammoths Endured". Live Science. Imaginova Cororporation. http://www.livescience.com/animals/041019_Mammoth_Island.html. Retrieved 2007-07-20.
- ^ "mammoth". Oxford English Dictionary. Oxford, England: Oxford University Press. June 2009.
- ^ Recently discovered long Woolly Mammoth tusk on display at the Illinois State Museum Illinois Department of Natural Resources press release, August 14, 2006
- ^ "Columbian Mammoth & Channel Island Mammoth". San Diego Zoo. http://library.sandiegozoo.org/factsheets/_extinct/mammoth/mammoth.htm. Retrieved 2010-06-15.
- ^ Rincon, Paul (2007-07-10). "Baby mammoth discovery unveiled". news.bbc.co.uk (The BBC). http://news.bbc.co.uk/1/hi/sci/tech/6284214.stm. Retrieved 2007-07-13.
- ^ Solovyov, Dmitry (2007-07-11). "Baby mammoth find promises breakthrough". reuters.com (Reuters). http://www.reuters.com/article/scienceNews/idUSL1178205120070711. Retrieved 2007-07-13.
- ^ Wakayama, Sayaka; et al. (3 November 2008). "Production of healthy cloned mice from bodies frozen at −20°C for 16 years". PNAS (Washington, DC: The National Academy of Sciences of the USA) 105 (45): 17318. doi:10.1073/pnas.0806166105. PMID 18981419. PMC 2582269. http://www.pnas.org/content/early/2008/10/31/0806166105. Retrieved 7 November 2008.
- ^ Nicholls, H. (2008). "Darwin 200: Let's make a mammoth". Nature 456 (7220): 310–314. doi:10.1038/456310a. PMID 19020594. 
- ^ Fulka Jr, J.; Loi, P.; Ptak, G.; Fulka, H.; John, J. (2009). "Hope for the mammoth?". Cloning and stem cells 11 (1): 1–4. doi:10.1089/clo.2008.0052. PMID 19090694. 
- ^ Staff (19 November 2008). "Scientists sequence woolly-mammoth genome". Penn State Live. Penn State University. http://live.psu.edu/story/36123. Retrieved 25 November 2008.
- ^ Fox, Maggie (19 November 2008). "Mammoth genome sequence may explain extinction". Reuters. http://www.reuters.com/article/newsOne/idUSTRE4AI6DB20081119?pageNumber=1&virtualBrandChannel=0. Retrieved 20 November 2008.
- ^ Gilbert, Thomas P.; et al. (28 September 2007). "Whole-Genome Shotgun Sequencing of Mitochondria from Ancient Hair Shafts". Science (Washington DC: American Association for the Advancement of Science) 317 (5846): pp 1927–1930. doi:10.1126/science.1146971. ISSN 1095-9203. PMID 17901335. http://rw.mammoth.psu.edu/pubs/hair.pdf. Retrieved 25 November 2008.
- ^ Wade, Nicholas (19 November 2008). "Regenerating a Mammoth for $10 Million". New York Times. http://www.nytimes.com/2008/11/20/science/20mammoth.html?pagewanted=1&_r=1. Retrieved 25 November 2008.
- ^ http://www.yomiuri.co.jp/dy/features/science/T110108003296.htm
- ^ http://news.blogs.cnn.com/2011/01/17/scientists-trying-to-clone-resurrect-extinct-mammoth/?hpt=T2
- ^ a b Kramer, Andrew E. (19 November 2008). "Trade in mammoth ivory, helped by global thaw, flourishes in Russia". New York Times. http://www.nytimes.com/2008/03/25/world/europe/25iht-mammoth.4.11415717.html. Retrieved 12 December 2009.
- ^ Anthony J. Stuart, Leopold D. Sulerzhitsky, Lyobov A. Orlova, Yaroslav V. Kuzmin and Adrian M. Lister: The latest woolly mammoths (Mammuthus primigenius Blumenbach) in Europe and Asia: a review of the current evidence Quaternary Science Reviews Volume 21, Issues 14-15, August 2002, Pages 1559-1569 online
- ^ Kristine J. Crossen, “5,700-Year-Old Mammoth Remains from the Pribilof Islands, Alaska: Last Outpost of North America Megafauna”, Geological Society of America Abstracts with Programs, Volume 37, Number 7, (Geological Society of America, 2005), 463.
- ^ David R. Yesner, Douglas W. Veltre, Kristine J. Crossen, and Russell W. Graham, “5,700-year-old Mammoth Remains from Qagnax Cave, Pribilof Islands, Alaska”, Second World of Elephants Congress, (Hot Springs: Mammoth Site, 2005), 200-203
- ^ Kh. A. Arslanov, G. T. Cook, Steinar Gulliksen, D.D. Harkness, Touvi Kankainen, E. M. Scott, Sergey Vartanyan, and Ganna I. Zaitseva, S. L. Vartanyan, “Consensus Dating of Remains from Wrangel Island”, Radiocarbon, Volume 40, Number 1, (Tucson: Radiocarbon, 1998), 289-294.
- ^ Sergei L. Vartanyan, Alexei N. Tikhonov, and Lyobov A. Orlova, “The Dynamic of Mammoth Distribution in the Last Refugia in Beringia”, Second World of Elephants Congress, (Hot Springs: Mammoth Site, 2005), 195.
- ^ Vartanyan, S.L.; Kh. A. Arslanov; T. V. Tertychnaya; S. B. Chernov (1995). "Radiocarbon Dating Evidence for Mammoths on Wrangel Island, Arctic Ocean, until 2000 BC". Radiocarbon (Department of Geosciences, The University of Arizona) 37 (1): pp 1–6. http://packrat.aml.arizona.edu/Journal/v37n1/vartanyan.html. Retrieved 2008-01-10.
- ^ a b Martin, P. S. (2005). Twilight of the Mammoths: Ice Age Extinctions and the Rewilding of America. University of California Press. ISBN 0520231414. http://books.google.com/?id=eThoCsL1hRAC.
- ^ a b Burney, D. A.; Flannery, T. F. (July 2005). "Fifty millennia of catastrophic extinctions after human contact". Trends in Ecology & Evolution (Elsevier) 20 (7): 395–401. doi:10.1016/j.tree.2005.04.022. PMID 16701402. http://www.anthropology.hawaii.edu/Fieldschools/Kauai/Publications/Publication%204.pdf. Retrieved 2009-06-12.
- ^ a b Fountain, Henry (22 December 2009). "DNA Shifts Timeline For Mammoths' Exit". The New York Times: p. 3. http://www.nytimes.com/2009/12/22/science/22obtundra.html. Retrieved 8 August 2010.
- ^ Levy, Sharon (2006): Clashing with Titans. BioScience 56(4): 292-298. DOI:10.1641/0006-3568(2006)56[292:CWT]2.0.CO;2 PDF fulltext
- ^ Lee, Christopher (11 June 2007). "New Theory on Old Debate: Comet Killed the Mammoth". The Washington Post. http://www.washingtonpost.com/wp-dyn/content/article/2007/06/10/AR2007061000915.html. Retrieved 15 January 2011.