Agate Fossil Beds National Monument is a U.S. National Monument near Harrison, Nebraska. The main features of the monument are a valley of the Niobrara River and the fossils found on Carnegie Hill and University Hill. The area largely consists of grass-covered plains. Plants on the site include prairie sandreed, blue grama, little bluestem and needle and thread grass, and the wildflowers

lupin ''Lupinus'', commonly known as lupin, lupine, or regionally bluebonnet etc., is a genus of plants in the legume family Fabaceae. The genus includes over 199 species, with centers of diversity in North and South America. Smaller centers occur ...

spiderwort ''Tradescantia'' () is a genus of 85 species of herbaceous perennial wildflowers in the family Commelinaceae, native to the Americas from southern Canada to northern Argentina, including the West Indies. Members of the genus are known by many co ...

, western wallflower and

sunflower The common sunflower (''Helianthus annuus'') is a large annual forb of the genus ''Helianthus'' grown as a crop for its edible oily seeds. Apart from cooking oil production, it is also used as livestock forage (as a meal or a silage plant), as ...

History

Entering Agate Fossil Beds National Monument

Originally the Agate Springs Ranch, a working cattle ranch, was owned by Capt. James Cook. The monument's museum collection also contains more than 500 artifacts from the Cook Collection of

Plains Indians Plains Indians or Indigenous peoples of the Great Plains and Canadian Prairies are the Native American tribes and First Nation band governments who have historically lived on the Interior Plains (the Great Plains and Canadian Prairies) of N ...

artifacts. The national monument was authorized on June 5, 1965, but was not established until June 14, 1997. The Harold J. Cook Homestead (Bone Cabin Complex) was listed on the National Register of Historic Places in 1977. Agate Fossil Beds is maintained by the National Park Service.

Paleontology

The site is best known for a large number of well-preserved Miocene fossils, many of which were found at dig sites on Carnegie and University Hills. Fossils from the

Harrison Formation The Harrison Formation is a geologic group in South Dakota and Nebraska. It preserves fossils from the Miocene. See also * List of fossiliferous stratigraphic units in South Dakota * Paleontology in South Dakota Paleontology in South Dakota r ...

and

Anderson Ranch Formation Anderson or Andersson may refer to: Companies * Anderson (Carriage), a company that manufactured automobiles from 1907 to 1910 * Anderson Electric, an early 20th-century electric car * Anderson Greenwood, an industrial manufacturer * Anderson Ra ...

, which date to the Arikareean in the North American land mammal classification, about 20 to 16.3 million years ago, are among some of the best specimens of Miocene

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

s. Species found in Agate include: * '' Miohippus'', '' Merychippus'' and '' Parahippus'', ancestors of the modern day horse. * ''

Diceratherium ''Diceratherium'' (meaning "two horned beast") is an extinct genus of rhinoceros endemic to North America, Europe, and Asia during the Oligocene through Miocene living from 33.9 to 11.6 mya, existing for approximately . Mass estimates for the ...

'', two-horned rhinoceros. * ''

Menoceras ''Menoceras'' ("Crescent Horns") is a genus of extinct, small rhinoceros endemic to most of southern North America and ranged as far south as Panama during the early Miocene epoch. It lived from around 30.7—19.7 Ma, existing for approximately ...

'', pony-sized rhinoceros, the most common animal found in the fossil beds. * '' Daphoenodon'', a bear dog. * ''

Promerycochoerus ''Promerycochoerus'' ("Before '' Merycochoerus''" or "Before Ruminating Hog") is an extinct genus of hippopotamus-like oreodont artiodactyl that lived in Central North America during the Early Miocene. The 1 m (3 ft 4 in) long c ...

'', a semiaquatic hippo-like oreodont. * '' Daeodon'', the largest Entelodont (giant pig-like ungulate). * ''

Stenomylus ''Stenomylus'' is an extinct genus of miniature camelid native to North America that died out around 30 million years ago. Its name is derived from the Greek (, "narrow") and (, "molar"). ''Stenomylus'' was extremely diminutive compared to ...

'' , gazelle-like camelids. * '' Oxydactylus'', giraffe-like camelids. * ''

Palaeocastor ''Palaeocastor'' ('prehistoric beaver') is an extinct genus of beavers that lived in the North American Badlands during the late Oligocene period to early Miocene. ''Palaeocastor'' was much smaller than modern beavers. There are several specie ...

'', land beavers that dug large corkscrew-shaped burrows (''Daemonelix''). * '' Moropus'', a

chalicothere Chalicotheres (from Greek '' chalix'', "gravel" and '' therion'', "beast") are an extinct clade of herbivorous, odd-toed ungulate (perissodactyl) mammals that lived in North America, Eurasia, and Africa from the Middle Eocene until the Early Plei ...

which are relatives of rhinos and horses. * '' Merychyus'', a sheep-like oreodont. * ''

Syndyoceras ''Syndyoceras'' is a small extinct genus of Artiodactyla, of the family Protoceratidae, endemic to central North America from the Miocene epoch (24.8—20.6 Ma), existing for approximately . Taxonomy ''Syndyoceras'' was named by Barbour (1 ...

'', antelope-like mammal and extinct relatives of artiodactyls.

Gallery

References

External links

* Official NPS website
Agate Fossil Beds National Monument
{{authority control Federal lands in Nebraska National Park Service National Monuments in Nebraska Cenozoic paleontological sites of North America Miocene paleontological sites Natural history of Nebraska Protected areas established in 1997 Dinosaur museums in the United States Natural history museums in Nebraska Museums in Sioux County, Nebraska Protected areas of Sioux County, Nebraska 1997 establishments in Nebraska Fossil parks in the United States Paleontology in Nebraska Paleontological protected areas in the United States 1997 in paleontology National Register of Historic Places in Sioux County, Nebraska