Daphoenus
Encyclopedia
Daphoenus is an extinct member of the family Amphicyonidae ("bear dogs") belonging to the class Mammalia, an extinct order of terrestrial
Terrestrial animal
Terrestrial animals are animals that live predominantly or entirely on land , as compared with aquatic animals, which live predominantly or entirely in the water , or amphibians, which rely on a combination of aquatic and terrestrial habitats...

 carnivore
Carnivore
A carnivore meaning 'meat eater' is an organism that derives its energy and nutrient requirements from a diet consisting mainly or exclusively of animal tissue, whether through predation or scavenging...

s belonging to the suborder Caniformia
Caniformia
Caniformia, or Canoidea , is a suborder within the order Carnivora. They typically possess a long snout and non-retractile claws . The Pinnipedia evolved from caniform ancestors and are accordingly assigned to this group...

, which inhabited North America
North America
North America is a continent wholly within the Northern Hemisphere and almost wholly within the Western Hemisphere. It is also considered a northern subcontinent of the Americas...

 from the Early Eocene subepoch to the Early Miocene
Early Miocene
The Early Miocene is a sub-epoch of the Miocene Epoch made up of two stages: the Aquitanian and Burdigalian stages....

 subepoch 42—16.3 Mya, existing for approximately .

Taxonomy

Daphoenus was named by Joseph Leidy
Joseph Leidy
Joseph Leidy was an American paleontologist.Leidy was professor of anatomy at the University of Pennsylvania, and later was a professor of natural history at Swarthmore College. His book Extinct Fauna of Dakota and Nebraska contained many species not previously described and many previously...

 (1853). Its species was Daphoenus vetus. It was assigned to Amphicyonidae by Leidy (1853) and Carroll (1988); and to Daphoeninae by Hunt (1998) and Hunt (2002).

Morphology

A single specimen was measured by Legendre and Roth in 1988 for estimated body mass..

Daphoenus was called "bear dogs" because they had characteristics of both bears and dogs. These animals were about the size of the present day coyote. Daphoenus vetus was the largest species. The male skulls could reach up to 20 cm in length. Daphoenus had short legs, and could only make quick sprints. These animals were not able to run long distances. It is thought that these animals ambushed their prey, and did some scavenging. Fossil footprints suggested that these animals walked in a flat-footed way. This is similar to the way that present day bears walk. Daphoenus dug burrows for their offspring to stay in and hide from their prey.

Species

Amphicyonids are discussed in Robert M. Hunt's article Global Climate and the Evolution of Large Mammalian Carnivores during the Later Cenozoic in North America. D. Vetus was the largest of the species. D. hartshornianus, D. lambei (syn. D. demilo), D. ruber, D. socialis, D. transversus, D. vetus (syn. Proamphicyon nebrascensis)

Fossil distribution

Daphoenus fossils found in late Oligocene rocks in the Great Plains
Great Plains
The Great Plains are a broad expanse of flat land, much of it covered in prairie, steppe and grassland, which lies west of the Mississippi River and east of the Rocky Mountains in the United States and Canada. This area covers parts of the U.S...

 are dated at ~28 Ma. Daphoenus survived
to 27 Ma in the Pacific Northwest
Pacific Northwest
The Pacific Northwest is a region in northwestern North America, bounded by the Pacific Ocean to the west and, loosely, by the Rocky Mountains on the east. Definitions of the region vary and there is no commonly agreed upon boundary, even among Pacific Northwesterners. A common concept of the...

 in the John Day
John Day Fossil Beds National Monument
John 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...

 beds of Oregon. Other sites include: Alachua County, Florida
Alachua County, Florida
Alachua County is a county located in the U.S. state of Florida. The U.S. Census Bureau 2006 estimate for the county is 227,120. Its county seat is Gainesville, Florida. Alachua County is the home of the University of Florida and is also known for its diverse culture, local music, and artisans...

 (Whitneyan
Whitneyan
The Whitneyan North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology , typically set from 33,300,000 to 30,800,000 years BP, a period of . It is usually considered to fall within the Early Oligocene...

) estimated at 31.1—24.3 Ma., Tecuya Canyon, California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...

 (Arikareean
Arikareean
The Arikareean North American Stage on the geologic timescale is the North American faunal stage according to the North American Land Mammal Ages chronology , typically set from 30,600,000 to 20,800,000 years BP, a period of . It is usually considered to overlap the Oligocene and Miocene epochs...

 age) 30.8—20.6 Ma., Haystack Member Formation, Wheeler County, Oregon
Wheeler County, Oregon
As of the census of 2000, there were 1,547 people, 653 households, and 444 families residing in the county. The population density was 1 people per square mile . There were 842 housing units at an average density of 0 per square mile...

 (Hemingfordian) 20.6—16.3 Ma., Lac Pelletier, Alberta, Canada (Duchesnean
Duchesnean
The Duchesnean North American Stage on the geologic timescale is a North American Land Mammal Age , with an age from 42 to 38 million years BP, representing . It falls within the Eocene epoch. The Duchesnean is preceded by the Uintan and followed by the Chadronian NALMA.The Duchesnean falls within...

) ~42 Ma.
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