Agate Fossil Beds National Monument
Encyclopedia
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 plain
s. Plants on the site include prairie sandreed, blue grama
, little bluestem
and needle and thread grass, and the wildflowers lupin
, spiderwort, western wallflower
and sunflower
s.
fossil
s, many of which were found at dig sites on Carnegie and University Hills. Fossils from the site, which date from about 20 million years ago, are among some of the best specimens of Miocene mammal
s. Species found at Agate include:
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 Indian 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
on August 24, 1977. Agate Fossil Beds is maintained by the National Park Service
.
U.S. National Monument
A National Monument in the United States is a protected area that is similar to a National Park except that the President of the United States can quickly declare an area of the United States to be a National Monument without the approval of Congress. National monuments receive less funding and...
near Harrison, Nebraska
Harrison, Nebraska
Harrison is a village in Sioux County, Nebraska, United States. The population was 279 at the 2000 census. It is the county seat of Sioux County.-Geography:Harrison is located at ....
. The main features of the Monument are a valley
Valley
In geology, a valley or dale is a depression with predominant extent in one direction. A very deep river valley may be called a canyon or gorge.The terms U-shaped and V-shaped are descriptive terms of geography to characterize the form of valleys...
of the Niobrara River
Niobrara River
The Niobrara River is a tributary of the Missouri River, approximately long, running through the U.S. states of Wyoming and Nebraska. The river drains one of the most arid sections of the Great Plains, and has a low flow for a river of its length...
, and the fossils found on Carnegie Hill and University Hill.
The area largely consists of grass
Grass
Grasses, or more technically graminoids, are monocotyledonous, usually herbaceous plants with narrow leaves growing from the base. They include the "true grasses", of the Poaceae family, as well as the sedges and the rushes . The true grasses include cereals, bamboo and the grasses of lawns ...
-covered plain
Plain
In geography, a plain is land with relatively low relief, that is flat or gently rolling. Prairies and steppes are types of plains, and the archetype for a plain is often thought of as a grassland, but plains in their natural state may also be covered in shrublands, woodland and forest, or...
s. Plants on the site include prairie sandreed, blue grama
Blue grama
Blue Grama, Bouteloua gracilis, is a long-lived, warm season, C4 perennial grass native to North America. It is most commonly found from Alberta east to Manitoba and south across the Rocky Mountains, Great Plains, and Midwest states to Mexico...
, little bluestem
Little bluestem
Schizachyrium scoparium, commonly known as little bluestem or beard grass, is a North American prairie grass. Little bluestem is a perennial bunchgrass and is prominent in tallgrass prairie, along with big bluestem , indiangrass and switchgrass...
and needle and thread grass, and the wildflowers lupin
Lupin
Lupinus, commonly known as Lupins or lupines , is a genus in the legume family . The genus comprises about 280 species , with major centers of diversity in South and western North America , and the Andes and secondary centers in the Mediterranean region and Africa Lupinus, commonly known as Lupins...
, spiderwort, western wallflower
Wallflower
Erysimum is a genus that includes about 180 species, both popular garden plants and many wild forms. The genus Cheiranthus is sometimes included herein whole or in part. Erysimum has recently adscribed to a monogeneric cruciferous tribe, Erysimeae...
and sunflower
Sunflower
Sunflower is an annual plant native to the Americas. It possesses a large inflorescence . The sunflower got its name from its huge, fiery blooms, whose shape and image is often used to depict the sun. The sunflower has a rough, hairy stem, broad, coarsely toothed, rough leaves and circular heads...
s.
History
The site is best known for the large number of well-preserved MioceneMiocene
The Miocene is a geological epoch of the Neogene Period and extends from about . The Miocene was named by Sir Charles Lyell. Its name comes from the Greek words and and means "less recent" because it has 18% fewer modern sea invertebrates than the Pliocene. The Miocene follows the Oligocene...
fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s, many of which were found at dig sites on Carnegie and University Hills. Fossils from the site, which date from about 20 million years ago, are among some of the best specimens of Miocene mammal
Mammal
Mammals are members of a class of air-breathing vertebrate animals characterised by the possession of endothermy, hair, three middle ear bones, and mammary glands functional in mothers with young...
s. Species found at Agate include:
- MiohippusMiohippusMiohippus was a genus of prehistoric horse existing longer than most Equidae. Miohippus lived in what is now North America during the Oligocene approximately 32-25 million years ago. While descending genera of this species lived during the Miocene period, the Miohippus was a horse of the Oligocene...
, an ancestor of the modern horseEvolution of the horseThe evolution of the horse pertains to the phylogenetic ancestry of the modern horse from the small dog-sized, forest-dwelling Hyracotherium over geologic time scales...
, - MenocerasMenocerasMenoceras 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 .-Behaviour:...
, a pony-sized rhinocerosRhinocerosRhinoceros , also known as rhino, is a group of five extant species of odd-toed ungulates in the family Rhinocerotidae. Two of these species are native to Africa and three to southern Asia....
, - AmphicyonAmphicyonAmphicyon is an extinct genus of large carnivorous bone-crushing mammals, known as bear-dogs, of the family Amphicyonidae, subfamily Amphicyoninae, from the Aquitanian Epoch until the Tortonian...
, a bear dogBear dogAmphicyonidae is an extinct family of large terrestrial carnivores belonging to the suborder Caniformia and which inhabited North America, Europe, Asia, and Africa from the Middle Eocene subepoch to the Pleistocene epoch 46.2—1.8 Mya, existing for approximately .-Taxonomy:Amphicyonidae was named...
, - Daeodon, the largest EntelodontEntelodontEntelodonts, sometimes nicknamed hell pigs or terminator pigs, is an extinct family of pig-like omnivores endemic to forests and plains of North America, Europe, and Asia from the middle Eocene to early Miocene epochs , existing for approximately .-Taxonomy:Entelodontidae was named by Richard...
(giant pig-like ungulate), - StenomylusStenomylusStenomylus is an extinct genus of miniature camelid native to North America. Its name is derived from the Greek στείνος, "narrow" and μύλος, "molar."...
, a gazelle-like camelidCamelidCamelids are members of the biological family Camelidae, the only living family in the suborder Tylopoda. Dromedaries, Bactrian Camels, llamas, alpacas, vicuñas, and guanacos are in this group....
, and - PalaeocastorPalaeocastorPalaeocastor is an extinct genus of beaver that lived in the North American Badlands during the late Oligocene period.-Habitat:...
, land beavers that dug large corkscrew-shaped burrows (Daemonelix)
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 Indian 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
National Register of Historic Places
The National Register of Historic Places is the United States government's official list of districts, sites, buildings, structures, and objects deemed worthy of preservation...
on August 24, 1977. Agate Fossil Beds is maintained by the National Park Service
National Park Service
The National Park Service is the U.S. federal agency that manages all national parks, many national monuments, and other conservation and historical properties with various title designations...
.
See also
- List of fossil sites
- Ashfall Fossil BedsAshfall Fossil BedsThe Ashfall Fossil Beds of Antelope County in northeastern Nebraska are among the rare preservation sites called lagerstätten, which preserve ecological "snapshots" from a moment in time, due to extraordinary local conditions that have preserved a range of fossilized organisms undisturbed.The...
- Florissant Fossil Beds National MonumentFlorissant Fossil Beds National MonumentFlorissant Fossil Beds National Monument is a United States National Monument in Teller County, Colorado, that is noted for its fossils. It is located in a mountain valley just west of Pikes Peak and holds spectacular remnants of prehistoric life...
- John Day Fossil Beds National MonumentJohn Day Fossil Beds National MonumentJohn Day Fossil Beds National Monument is a U.S. National Monument in Wheeler and Grant counties in east-central Oregon. Located within the John Day River basin and managed by the National Park Service, the park is known for its well-preserved layers of fossil plants and mammals that lived in the...
- Scotts Bluff National MonumentScotts Bluff National MonumentScotts Bluff National Monument in western Nebraska includes an important 19th century landmark on the Oregon Trail and Mormon Trail. The National Monument contains multiple bluffs located on the south side of the North Platte River; it is named for one prominent bluff called Scotts Bluff, which...
External links
- Official NPS website: Agate Fossil Beds National Monument