Bear dog
Encyclopedia
Amphicyonidae is an extinct family
of large terrestrial
carnivore
s belonging to the suborder Caniformia
(meaning "dog-like") 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 .
Amphicyonidae was named by Haeckel (1886) [also attributed to Trouessart 1885]. It was assigned to Carnivora
by Sach and Heizmann (2001); to Arctoidea
by Hunt (2001), Hunt (2002) and Hunt (2002); affirmed as Arctoidea by Zhai et al. (2003); affirmed to Arctoidea by Carroll (1988), Hunt (1998) and Wang et al. (2005); and to Caniformia
by Morlo et al. (2007).
. The earliest to appear is the (rather large) Ysengrinia
(30—20 Mya), followed by Cynelos
(24—7 Mya) and Amphicyon
(23—5 Mya). These animals would have followed ungulate
s and other mammals to the New World for a period of approximately 7 million years. The New World
amphicyonids of the subfamilies Daphoeninae (42-16 Mya) and Temnocyoninae (33-20 Mya) coexisted with the Old World
counterparts. Note that the (often similar looking) members of the family Hemicyonidae
are often called "bear-dogs" as well (although they are increasingly referred to as "dog-bears" to avoid confusion).
Amphicyonids were as small as 5 kilograms (11 lb) and as large as 100 to 600 kg (220.5 to 1,322.8 lb) and evolved from wolf-like to bear-like. The diet of the amphicyonids was fully carnivorous as opposed to hypercarnivorous
to mesocarnivorous
in Canidae.
s), some evidence suggests that they may instead be basal caniforms. (Hunt, 2004b). They were about as tall as the American black bear and were most likely ambushers because their legs were made for short, sudden bursts of speed. Bear-dog also nested their young in underground burrows.
During the early Miocene, a number of large amphicyonids migrated from Eurasia
into North America. These taxa belong to the Old World amphicyonid sub-family Amphicyoninae. The earliest to appear is the large bear dog Ysengrinia Ginsburg, followed by Cynelos Jourdan, and then by Amphicyon. This influx of amphicyonines, accompanied by other Old World ungulates and small mammals, indicates a prolonged interval (from 23 to 16.5 Ma) of faunal exchange between Asia and North America in the early Miocene, using the trans-Beringian route. New World daphoenines (Daphoenodon, Borocyon) and temnocyonines coexisted with Old World amphicyonines (Ysengrinia, Amphicyon, Cynelos) 23.7-17.5 million years ago. These are the largest terrestrial carnivorans 50 kilograms (110.2 lb) to 200 kilograms (440.9 lb) that evolved on the North American continent up to this time. The immigrant amphicyonines Ysengrinia, Cynelos and Amphicyon appear at 23, 19.2, and 18.8 Ma, respectively, and herald the beginning of a Eurasian amphicyonine migration into North America that continued into the mid-Miocene.
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
of large 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...
(meaning "dog-like") and 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...
, Europe
Europe
Europe is, by convention, one of the world's seven continents. Comprising the westernmost peninsula of Eurasia, Europe is generally 'divided' from Asia to its east by the watershed divides of the Ural and Caucasus Mountains, the Ural River, the Caspian and Black Seas, and the waterways connecting...
, Asia
Asia
Asia is the world's largest and most populous continent, located primarily in the eastern and northern hemispheres. It covers 8.7% of the Earth's total surface area and with approximately 3.879 billion people, it hosts 60% of the world's current human population...
, and Africa
Africa
Africa is the world's second largest and second most populous continent, after Asia. At about 30.2 million km² including adjacent islands, it covers 6% of the Earth's total surface area and 20.4% of the total land area...
from the Middle Eocene subepoch to the Pleistocene
Pleistocene
The Pleistocene is the epoch from 2,588,000 to 11,700 years BP that spans the world's recent period of repeated glaciations. The name pleistocene is derived from the Greek and ....
epoch 46.2—1.8 Mya, existing for approximately .
Taxonomy
Carnivora
The diverse order Carnivora |Latin]] carō "flesh", + vorāre "to devour") includes over 260 species of placental mammals. Its members are formally referred to as carnivorans, while the word "carnivore" can refer to any meat-eating animal...
by Sach and Heizmann (2001); to Arctoidea
Arctoidea
Arctoidea is a superfamily of extinct and extant mostly carnivorous mammals which include the extinct group Hemicyonidae , and extant groups Musteloidea , Nothocyon, Pinnipedia , and Ursidae , found in all continents from the Eocene, 46 Ma ago, to the present, approximately ..-Taxonomy:Arctoidea...
by Hunt (2001), Hunt (2002) and Hunt (2002); affirmed as Arctoidea by Zhai et al. (2003); affirmed to Arctoidea by Carroll (1988), Hunt (1998) and Wang et al. (2005); and to 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...
by Morlo et al. (2007).
Origins
Amphicyonids, often referred to as "bear dogs", crossed from Europe to North America during the Miocene epoch and are considered an Old World taxonTaxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
. The earliest to appear is the (rather large) Ysengrinia
Ysengrinia
Ysengrinia is an extinct genus of large, mostly carnivorous bone-crushing mammals known as bear dogs, of the family Amphicyonidae endemic to Europe, Africa, and North America during the Miocene living from 22.4—20 Ma and existed for approximately ....
(30—20 Mya), followed by Cynelos
Cynelos
Cynelos is a large extinct genus of terrestrial carnivores belonging to the suborder Caniformia, family Amphicyonidae , and which inhabited North America, Europe Asia, and Africa from the Early Miocene subepoch to the Late Miocene subepoch 24.8—7.2 Mya, existing for approximately .Dentition of...
(24—7 Mya) and Amphicyon
Amphicyon
Amphicyon 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...
(23—5 Mya). These animals would have followed ungulate
Ungulate
Ungulates are several groups of mammals, most of which use the tips of their toes, usually hoofed, to sustain their whole body weight while moving. They make up several orders of mammals, of which six to eight survive...
s and other mammals to the New World for a period of approximately 7 million years. The New World
New World
The New World is one of the names used for the Western Hemisphere, specifically America and sometimes Oceania . The term originated in the late 15th century, when America had been recently discovered by European explorers, expanding the geographical horizon of the people of the European middle...
amphicyonids of the subfamilies Daphoeninae (42-16 Mya) and Temnocyoninae (33-20 Mya) coexisted with the Old World
Old World
The Old World consists of those parts of the world known to classical antiquity and the European Middle Ages. It is used in the context of, and contrast with, the "New World" ....
counterparts. Note that the (often similar looking) members of the family Hemicyonidae
Hemicyonidae
Hemicyonidae is an extinct family of so-called "dog-bears", literally "Half Dog" , bear-like carnivoran living in Europe, North America, Africa, and Asia during the Oligocene through Miocene epochs 33.9—5.3 Ma, existing for approximately ....
are often called "bear-dogs" as well (although they are increasingly referred to as "dog-bears" to avoid confusion).
Amphicyonids were as small as 5 kilograms (11 lb) and as large as 100 to 600 kg (220.5 to 1,322.8 lb) and evolved from wolf-like to bear-like. The diet of the amphicyonids was fully carnivorous as opposed to hypercarnivorous
Hypercarnivore
A hypercarnivore is an animal which has a diet that is more than 70% meat, with the balance consisting of non-animal foods such as fungi, fruits or other plant material. Some examples include the big cats, dolphins, eagles, snakes, marlin, most sharks, and such invertebrates as octopuses and sea...
to mesocarnivorous
Mesocarnivore
A mesocarnivore is an animal whose diet consists of 50–70% meat with the balance consisting of nonvertebrate foods which may include fungi, fruits, and other plant material...
in Canidae.
Evolution
While amphicyonids have traditionally been viewed as closely related to ursids (bearBear
Bears are mammals of the family Ursidae. Bears are classified as caniforms, or doglike carnivorans, with the pinnipeds being their closest living relatives. Although there are only eight living species of bear, they are widespread, appearing in a wide variety of habitats throughout the Northern...
s), some evidence suggests that they may instead be basal caniforms. (Hunt, 2004b). They were about as tall as the American black bear and were most likely ambushers because their legs were made for short, sudden bursts of speed. Bear-dog also nested their young in underground burrows.
During the early Miocene, a number of large amphicyonids migrated from Eurasia
Eurasia
Eurasia is a continent or supercontinent comprising the traditional continents of Europe and Asia ; covering about 52,990,000 km2 or about 10.6% of the Earth's surface located primarily in the eastern and northern hemispheres...
into North America. These taxa belong to the Old World amphicyonid sub-family Amphicyoninae. The earliest to appear is the large bear dog Ysengrinia Ginsburg, followed by Cynelos Jourdan, and then by Amphicyon. This influx of amphicyonines, accompanied by other Old World ungulates and small mammals, indicates a prolonged interval (from 23 to 16.5 Ma) of faunal exchange between Asia and North America in the early Miocene, using the trans-Beringian route. New World daphoenines (Daphoenodon, Borocyon) and temnocyonines coexisted with Old World amphicyonines (Ysengrinia, Amphicyon, Cynelos) 23.7-17.5 million years ago. These are the largest terrestrial carnivorans 50 kilograms (110.2 lb) to 200 kilograms (440.9 lb) that evolved on the North American continent up to this time. The immigrant amphicyonines Ysengrinia, Cynelos and Amphicyon appear at 23, 19.2, and 18.8 Ma, respectively, and herald the beginning of a Eurasian amphicyonine migration into North America that continued into the mid-Miocene.
Classification
- Family Amphicyonidae
- Subfamily Amphicyoninae
- Genus AgnotheriumAgnotheriumAgnotherium is an extinct genus of large terrestrial carnivores belonging to the suborder Caniformia, family Amphicyonidae , and which inhabited Euroasia and North Africa from the Early Miocene subepoch to the Middle Miocene subepoch 16.9—11.6 Mya, existing for approximately .Agnotherium was...
- A. antiquus
- A. grivense
- Genus 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. frendens
- A. bohemicus
- A. castellanus
- A. caucasicus
- A. galushai
- A. giganteus
- A. ingens
- A. intermedius (typeType speciesIn biological nomenclature, a type species is both a concept and a practical system which is used in the classification and nomenclature of animals and plants. The value of a "type species" lies in the fact that it makes clear what is meant by a particular genus name. A type species is the species...
) - A. laugnacensis
- A. longiramus
- A. major
- A. pontoni
- A. reinheimeri
- A. riggsi
- A. tairumensis
- A. ulungurensis
- Genus Amphicyonopsis
- A. serus
- Genus BrachycyonBrachycyonBrachycyon is an extinct genus of terrestrial carnivores belonging to the suborder Caniformia, family Amphicyonidae , and which inhabited Euroasia and North America. Brachycyon was named by Filhol...
- B. reyi
- B. palaeolycos
- B. gaudryi
- Genus CynelosCynelosCynelos is a large extinct genus of terrestrial carnivores belonging to the suborder Caniformia, family Amphicyonidae , and which inhabited North America, Europe Asia, and Africa from the Early Miocene subepoch to the Late Miocene subepoch 24.8—7.2 Mya, existing for approximately .Dentition of...
- C. caroniavorus
- C. crassidens
- C. helbingo
- C. idoneus
- C. jourdan
- C. lemanensis
- C. pivetaui
- C. rugosidens
- C. schlosseri
- C. sinapius
- Genus CynodictisCynodictisCynodictis, is a member of extinct terrestrial carnivores belonging to the family Amphicyonidae, suborder Caniformia, and which inhabited Euroasia and Asia from the Late Eocene subepoch to the Early Oligocene subepoch living from 37.2—28.4 Ma, existing for approximately .Cynodictis was one of the...
- C. lacustris
- Genus EuroamphicyonEuroamphicyonEuroamphicyon is a member of extinct terrestrial carnivores belonging to the family Amphicyonidae, suborder Caniformia, and which inhabited Europe during the Miocene.-Morphology:...
- E. olisiponensis
- Genus GobicyonGobicyonGobicyon is an extinct genus of terrestrial carnivore belonging to the family Canidae endemic to Central Asia from the Early Miocene subepoch through Late Miocene subepoch 13.6—11.6 Ma, existing for approximately ....
- G. macrognathus
- G. zhegalloi
- Genus GuangxicyonGuangxicyonGuangxicyon is an extinct genus of terrestrial carnivores belonging to the suborder Caniformia, family Amphicyonidae , and which inhabited Central Asia from the Late Eocene subepoch to the Late Miocene subepoch 37—33 Ma, existing for approximately .Guangxicyon was named by Zhai et al. in 2003. Its...
- G. sinoamericanus
- Genus HaplocyonHaplocyonHaplocyon is an extinct genus of terrestrial carnivores belonging to the suborder Caniformia, family Amphicyonidae named by Schlosser in 1901.-Sister genera:...
- H. elegans
- H. crucians
- Genus HaplocyonoidesHaplocyonoidesHaplocyonoides is an extinct family of terrestrial carnivores belonging to the suborder Caniformia, family Amphicyonidae , and which inhabited Europe from the Early Miocene subepoch —...
- H. mordax
- H. serbiae
- H. ponticus
- Genus HaplocyonopsisHaplocyonopsisHaplocyonopsis is an extinct genus of terrestrial carnivores belonging to the suborder Caniformia, family Amphicyonidae .Haplocyonopsis was named by de Bonis and was assigned to Amphicyonidae by Carroll .-Sister genera:...
- Genus Harpagocyon
- Genus Heducides
- Genus IschyrocyonIschyrocyonIschyrocyon is an extinct genus of large, mostly carnivorous mammals known as bear dogs, of the family Amphicyonidae, subfamily Amphicyoninae, which inhabited North America during the Miocene living from ~16.3—10.3 Ma and existed for approximately .-Taxonomy:Ischyrocyon was named by Matthew and...
- I. gidleyi
- Genus ParadaphoenusParadaphoenusParadaphoenus is a physically small member of the extinct family of terrestrial carnivores belonging to the suborder Caniformia, family Amphicyonidae , and which inhabited North America from the Early Oligocene subepoch to the Early Miocene subepoch living 33.9—16.3 Ma, existing for approximately...
- P. cuspigerus
- P. minimus
- P. tooheyi
- Genus Pericyon
- Genus PliocyonPliocyonPliocyon is a physically large member of the extinct family Amphicyonidae of terrestrial carnivores belonging to the suborder Caniformia, and which inhabited North America from the Early Miocene subepoch to the Middle Miocene subepoch 20.6—13.6 Ma, existing for approximately .Pliocyon was named by...
- P. medius
- P. robustus
- Genus Proamphicyon
- Genus Protemnocyon
- Genus PseudarctosPseudarctosPseudarctos is a member of the extinct family Amphicyonidae of terrestrial carnivores belonging to the suborder Caniformia, and which inhabited Euroasia from the Early Miocene subepoch to the Miocene epoch 16.9—11.1 Ma, existing for approximately ....
- P. bavaricus
- Genus PseudamphicyonPseudamphicyonPseudamphicyon is a member of the extinct family Amphicyonidae of terrestrial carnivores belonging to the suborder Caniformia.Pseudamphicyon was named Schlosser in 1899 and was assigned to Amphicyonidae by Carroll .-Sister genera:...
- P. bavaricus
- Genus PseudocyonPseudocyonPseudocyon, also known as Amphicyonopsis, is an extinct genus of terrestrial carnivores belonging to the suborder Caniformia, family of Amphicyonidae and which inhabited Euroasia and North America from the Miocene epoch to the Late Miocene subepoch living 23.3—7.2 Mya...
- P. sansaniensis
- P. steinheimensis
- P. styriacus
- Genus PseudocyonopsisPseudocyonopsisPseudocyonopsis is a member of the extinct family Amphicyonidae, a terrestrial carnivore belonging to the order Caniformia.Pseudocyonopsis was named by Kuss in 1965 and was assigned to Amphicyonidae by Carroll .-Sister genera:...
- P. ambiguus
- P. antiquus
- P. quercensis
- Genus Symplectocyon
- Genus YsengriniaYsengriniaYsengrinia is an extinct genus of large, mostly carnivorous bone-crushing mammals known as bear dogs, of the family Amphicyonidae endemic to Europe, Africa, and North America during the Miocene living from 22.4—20 Ma and existed for approximately ....
- Y. americanus
- Y. depereti
- Y. geraniana
- Y. ginsburg
- Y. tolosana
- Genus Agnotherium
- Subfamily Daphoeninae(North America)
- Genus AdilophontesAdilophontesAdilophontes is an extinct genus of large, mostly carnivorous bone-crushing mammals known as bear dogs, of the family Amphicyonidae, endemic to North America during the Oligocene to Miocene, living from 24.8—20.6 Ma and existed for approximately ....
- A. brachykolos
- Genus Borocyon
- Genus Brachyrhyncocyon
- B. dodgei
- B. montanus
- Genus DaphoenictisDaphoenictisDaphoenictis is an extinct cat-like genus of the family Amphicyonidae , subfamily Daphoeninae, endemic to North America during the Late Eocene-Oligocene epochs, existing for approximately 10.2 million years. Daphoenictis' geographical range was mid-western North America; from central Canada, to...
- D. tedfordi
- Genus Daphoenodon
- D. falkenbachi
- D. notionastes
- D. robustum
- D. periculosus
- D. skinneri
- D. superbus
- Genus DaphoenusDaphoenusDaphoenus is an extinct member of the family Amphicyonidae belonging to the class Mammalia, an extinct order of terrestrial carnivores belonging to the suborder Caniformia, which inhabited North America from the Early Eocene subepoch to the Early Miocene subepoch 42—16.3 Mya, existing for...
- D. dodgei or Daphoenocyon dodgei
- D. felinus
- D. hartshornianus
- D. inflatus
- D. lambei
- D. nebrascensis
- D. socialis
- D. transversus
- D. vetus
- Genus ParadaphoenusParadaphoenusParadaphoenus is a physically small member of the extinct family of terrestrial carnivores belonging to the suborder Caniformia, family Amphicyonidae , and which inhabited North America from the Early Oligocene subepoch to the Early Miocene subepoch living 33.9—16.3 Ma, existing for approximately...
- P. cuspigerus
- P. minimus
- P. tooheyi
- Genus Adilophontes
- Subfamily Temnocyoninae (North America)
- Genus MammacyonMammacyonMammacyon is an extinct genus of large, mostly carnivorous bone-crushing mammals known as bear dogs, of the family Amphicyonidae endemic to North America during the Oligocene to Miocene living from 30.8—20.6 Ma and existed for approximately .-Taxonomy:...
- M. obtusidens
- Genus Temnocyon
- T. altigenis
- T. ferox
- T. percussor
- T. venator
- Genus Mammacyon
- Subfamily Thanmastocyoninae
- Subfamily Amphicyoninae