The Mammoth Site is a

museum A museum ( ; plural museums or, rarely, musea) is a building or institution that cares for and displays a collection of artifacts and other objects of artistic, cultural, historical, or scientific importance. Many public museums make th ...

and

paleontological Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of foss ...

site near Hot Springs, South Dakota, in the

Black Hills The Black Hills ( lkt, Ȟe Sápa; chy, Moʼȯhta-voʼhonáaeva; hid, awaxaawi shiibisha) is an isolated mountain range rising from the Great Plains of North America in western South Dakota and extending into Wyoming, United States. Black ...

. It is an active paleontological excavation site at which research and excavations are continuing. The facility encloses a prehistoric

sinkhole A sinkhole is a depression or hole in the ground caused by some form of collapse of the surface layer. The term is sometimes used to refer to doline, enclosed depressions that are locally also known as ''vrtače'' and shakeholes, and to openi ...

that formed and was slowly filled with

sediment Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sand ...

s during the

Pleistocene The Pleistocene ( , often referred to as the ''Ice age'') is the geological Epoch (geology), epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was fina ...

era. The

sedimentary Sedimentary rocks are types of rock that are formed by the accumulation or deposition of mineral or organic particles at Earth's surface, followed by cementation. Sedimentation is the collective name for processes that cause these particles ...

fill of the sinkhole contains the remains of Pleistocene

fauna Fauna is all of the animal life present in a particular region or time. The corresponding term for plants is '' flora'', and for fungi, it is '' funga''. Flora, fauna, funga and other forms of life are collectively referred to as '' biota''. ...

and

flora Flora is all the plant life present in a particular region or time, generally the naturally occurring ( indigenous) native plants. Sometimes bacteria and fungi are also referred to as flora, as in the terms '' gut flora'' or '' skin flora''. ...

preserved by entrapment and burial within a

. As of 2016, the remains of 61

mammoth A mammoth is any species of the extinct elephantid genus ''Mammuthus'', one of the many genera that make up the order of trunked mammals called proboscideans. The various species of mammoth were commonly equipped with long, curved tusks an ...

s, including 58 North American Columbian and 3 woolly mammoths had been recovered. Mammoth bones were found at the site in 1974, and a museum and building enclosing the site were established. The museum now contains an extensive collection of mammoth remains.Agenbroad, L.D., 1994. "Geology, hydrology, and excavation of the site." In Agenbroad, L.D. and Mead, J.I., eds., pp. 15-27. "The Hot Springs Mammoth Site: A Decade of Field and Laboratory Research in the Paleontology, Geology, and Paleoecology." The Mammoth Site of South Dakota. Inc. Hot Springs, South Dakota.Laury, R.L., 1980. "Paleoenvironment of a late Quaternary mammoth-bearing sinkhole deposit, Hot Springs, South Dakota." Geological Society of America Bulletin, 91(8), pp.465-475.

Formation

During the Late

, the sinkhole at Mammoth Site of Hot Springs formed when a cavern in the Minnelusa Limestone collapsed. This cavern collapse created a steep-sided

, that was about deep and by wide at the surface within a Pleistocene terrace underlain by Spearfish Shale. The sinkhole is the surface expression of a vertical breccia pipe which provided a chimney-like path that allowed warm artesian water to percolate upward and fill the sinkhole with a steeply-sided pond. Arctodus Simus, Hot Springs, South Dakota

Arctodus Simus, Hot Springs, South Dakota

Based on observations from modern ponds and lakes, it is estimated that this pond slowly infilled with silt over a period of 350–700 years. The presence of worm burrows and mammoth footprints found throughout these sediments, demonstrate that the laminated sediments within this sinkhole accumulated slowly and contemporaneously along with the mammoth remains over a long period of time. Likely enticed by warm water and pond vegetation, mammoths entered the pond to eat, drink or bathe. Because of the steep sides of very slippery Spearfish Shale, mammoths were occasionally trapped as they were unable to find a foothold and climb out of the sinkhole during periods of low water. Trapped in the sinkhole, the mammoths ultimately died of starvation, exhaustion, or drowned in the pond. MammothFootImpressions25

Eventually the sinkhole filled, and the artesian spring diverted to the lower elevation of Fall River, as the river cut deeper in the valley floor. Over thousands of years, the "hardened mud plug" inside the dried-up pond has remained stable. The surrounding sediment was subsequently eroded, leaving the sinkhole as a high point on the landscape.

Paleontology

Warm artesian-fed spring waters created a pond that was attractive to wildlife. Findings at the site include the remains of

megafauna In terrestrial zoology, the megafauna (from Greek μέγας ''megas'' "large" and New Latin ''fauna'' "animal life") comprises the large or giant animals of an area, habitat, or geological period, extinct and/or extant. The most common thresho ...

such as giant short-faced bears along with those of shrub oxen, American camel,

llama The llama (; ) (''Lama glama'') is a domesticated South American camelid, widely used as a meat and pack animal by Andean cultures since the Pre-Columbian era. Llamas are social animals and live with others as a herd. Their wool is soft ...

wolves The wolf (''Canis lupus''; : wolves), also known as the gray wolf or grey wolf, is a large canine native to Eurasia and North America. More than thirty subspecies of ''Canis lupus'' have been recognized, and gray wolves, as popularly un ...

coyote The coyote (''Canis latrans'') is a species of canine native to North America. It is smaller than its close relative, the wolf, and slightly smaller than the closely related eastern wolf and red wolf. It fills much of the same ecological nich ...

s, birds,

mink Mink are dark-colored, semiaquatic, carnivorous mammals of the genera '' Neogale'' and '' Mustela'' and part of the family Mustelidae, which also includes weasels, otters, and ferrets. There are two extant species referred to as "mink": ...

ferret The ferret (''Mustela furo'') is a small, domesticated species belonging to the family Mustelidae. The ferret is most likely a domesticated form of the wild European polecat (''Mustela putorius''), evidenced by their interfertility. Other mus ...

prairie dog Prairie dogs (genus ''Cynomys'') are herbivorous Burrow, burrowing Marmotini , ground squirrels native to the grasslands of North America. Within the genus are five species: black-tailed prairie dog, black-tailed, white-tailed prairie dog, wh ...

vole Voles are small rodents that are relatives of lemmings and hamsters, but with a stouter body; a longer, hairy tail; a slightly rounder head; smaller eyes and ears; and differently formed molars (high-crowned with angular cusps instead of lo ...

s, and moles.

Invertebrate Invertebrates are a paraphyletic group of animals that neither possess nor develop a vertebral column (commonly known as a ''backbone'' or ''spine''), derived from the notochord. This is a grouping including all animals apart from the chorda ...

discoveries include several species of

clam Clam is a common name for several kinds of bivalve molluscs. The word is often applied only to those that are edible and live as infauna, spending most of their lives halfway buried in the sand of the seafloor or riverbeds. Clams have two shel ...

snail A snail is, in loose terms, a shelled gastropod. The name is most often applied to land snails, terrestrial pulmonate gastropod molluscs. However, the common name ''snail'' is also used for most of the members of the molluscan class ...

s, and

slug Slug, or land slug, is a common name for any apparently shell-less terrestrial gastropod mollusc. The word ''slug'' is also often used as part of the common name of any gastropod mollusc that has no shell, a very reduced shell, or only a ...

s.Anonymous, 2008
List of recovered species at the Hot Springs Mammoth Site (85 species on January 2008)
Mammoth Site of South Dakota. Inc. Hot Springs, South Dakota. The majority of the mammoth remains have been identified as those of

Columbian Mammoth The Columbian mammoth (''Mammuthus columbi'') is an extinct species of mammoth that inhabited the Americas as far north as the Northern United States and as far south as Costa Rica during the Pleistocene epoch. It was one of the last in a line ...

s, although the remains of three

Woolly mammoth The woolly mammoth (''Mammuthus primigenius'') is an extinct species of mammoth that lived during the Pleistocene until its extinction in the Holocene epoch. It was one of the last in a line of mammoth species, beginning with '' Mammuthus s ...

s have been found as well. Mammoths that slipped into the sinkhole found it difficult to escape. Researchers measuring the pelvic bones of the remains have determined that most of the victims were young males.Agenbroad, L.D., 1997. "This Land/South Dakota: Mammoth Site." Natural History Magazine. (October 1997) 106(9):77-79. A hypothesis drawn from observations of modern

elephant Elephants are the largest existing land animals. Three living species are currently recognised: the African bush elephant, the African forest elephant, and the Asian elephant. They are the only surviving members of the family Elephantida ...

matriarchal Matriarchy is a social system in which women hold the primary power positions in roles of authority. In a broader sense it can also extend to moral authority, social privilege and control of property. While those definitions apply in general En ...

societies, in which these group members are expelled, concludes that this group was inclined to the risk-taking behavior that led to their entrapment.

Chronology

Initially, The Mammoth Site was estimated to be about 20,000 years old. This estimate was made on the basis of the faunal remains that are found in association with the mammoth remains. The presence of the remains of Pleistocene bear, camel, antelope, and shrub-ox indicated to geologists and paleontologists that sinkhole at this site might be filled with Late Pleistocene, possibly terminal Pleistocene, sediments. Numerous attempts have been made to radiocarbon date these sediments. Initially, several attempts were made to radiocarbon date collagen from scrap mammoth bone recovered from the site. All of these attempts failed to recover sufficient collagen from the bone samples to allow dating of this fraction. Later, samples of the bone apatite (hydroxyapatite) fraction from mammoth bones were radiocarbon dated. Two samples of the heat treated apatite fraction yielded radiocarbon dates of 19,260±1520 B.P and 20,770±350 B.P. Samples of bone apatite, which were not heat treated, yielded radiocarbon dates of 21,000±700, 25,640±320, and 26,075+975/-790 B.P. A single sample of bone carbonate was radiocarbon dated at 36,960±1170 B.P. The circa 26,000 B.P. time frame has been widely used by researchers as the approximate the time that sediments and mammoths bones accumulated within the sinkhole within The Mammoth Site. However, radiocarbon dates derived from bone apatite are now known to be highly unreliable and at best represent the minimum age of the bone datedMahan, S.A., Hanson, P.R., Mead, J., Holen, S., and Wilkins, J., 2016
“Dating the Hot Springs, South Dakota Mammoth Sinkhole Site.”
Geological Society of America Abstracts with Programs. 48:7. doi: 10.1130/abs/2016AM-281798 Because of the limitations of radiocarbon dates derived from bone apatite, a tooth plate from a mammoth was dated and uranium series dating and sediments enclosing the mammoth bones were dated using thermoluminescence (TL) and optically stimulated luminescence (OSL). The tooth plate yielded a uranium series date of 128,966 B.P. The results of the TL dating were apparently never published and preliminary OSL ages indicate that the sinkhole and its associated sediments and mammoth bones are indeed older than 26 ka. Digger, and bones, Mammoth Site, Hot Springs

Digger, and bones, Mammoth Site, Hot Springs

Museum

In 1974, a construction worker, George Hanson, unearthed unusual bones while the area was being prepared for a new subdivision. His son recognized one of the finds as a mammoth tooth. The landowner Phil Anderson agreed to further investigation, and a complete skull and tusk were found in 1974. Phil Anderson agreed to donate the entire bone bed and mineral rights to the nonprofit organization and along with the work performed by amateur and professional excavators, led to its status as a museum, and it was designated a

National Natural Landmark The National Natural Landmarks (NNL) Program recognizes and encourages the conservation of outstanding examples of the natural history of the United States. It is the only national natural areas program that identifies and recognizes the best ...

in 1980. Initially the finds were mapped on a string grid; since then the mapping systems have increasingly relied on computerized technologies.Esker, D.A., 2009
“It's All about Context - Remapping mammoth bone bed with ArcGIS.”
Esri, ArcUser, Spring 2009. pp. 24-26. The Mammoth Site is a

501(c) A 501(c) organization is a nonprofit organization in the federal law of the United States according to Internal Revenue Code (26 U.S.C. § 501(c)) and is one of over 29 types of nonprofit organizations exempt from some federal income taxes. ...

-3 non-profit organization. The museum is open to the public. Earthwatch volunteers participate in excavations during July. The museum's visiting scientists have included specialists from

Mexico Mexico (Spanish language, Spanish: México), officially the United Mexican States, is a List of sovereign states, country in the southern portion of North America. It is borders of Mexico, bordered to the north by the United States; to the so ...

Italy Italy ( it, Italia ), officially the Italian Republic, ) or the Republic of Italy, is a country in Southern Europe. It is located in the middle of the Mediterranean Sea, and its territory largely coincides with the homonymous geographical ...

Netherlands ) , anthem = ( en, "William of Nassau") , image_map = , map_caption = , subdivision_type = Sovereign state , subdivision_name = Kingdom of the Netherlands , established_title = Before independence , established_date = Spanish Netherl ...

Great Britain Great Britain is an island in the North Atlantic Ocean off the northwest coast of continental Europe. With an area of , it is the largest of the British Isles, the largest European island and the ninth-largest island in the world. It ...

Russia Russia (, , ), or the Russian Federation, is a transcontinental country spanning Eastern Europe and Northern Asia. It is the largest country in the world, with its internationally recognised territory covering , and encompassing one-ei ...

, and

Germany Germany,, officially the Federal Republic of Germany, is a country in Central Europe. It is the second most populous country in Europe after Russia, and the most populous member state of the European Union. Germany is situated betwee ...

. The museum also houses a collection of Clovis and

Folsom Folsom may refer to: People * Folsom (surname) Places in the United States * Folsom, Perry County, Alabama * Folsom, Randolph County, Alabama * Folsom, California * Folsom, Georgia * Folsom, Louisiana * Folsom, Missouri * Folsom, New Jerse ...

artifacts. and sponsors outreach programs for students from elementary to graduate-school levels.Thompson, K.M., 2004
"The Mammoth Site of Hot Springs South Dakota: Strategies for educational development in a paleontological site."
Geological Society of America Abstracts with Programs, Vol. 36, No. 5, p. 350, Retrieved 2017-09-24.

References

External links

The Mammoth Site of Hot Springs, South Dakota
- official site
Magazine article
{{authority control 1974 in paleontology Archaeological museums in South Dakota Black Hills Fossil parks in the United States Museums in Fall River County, South Dakota National Natural Landmarks in South Dakota Native American museums in South Dakota Natural history museums in South Dakota Paleontology in South Dakota Pleistocene paleontological sites of North America