Borophaginae
Encyclopedia
The subfamily Borophaginae is an extinct group of canids called "bone crushing dogs" that were endemic to North America
during the Oligocene
to Pliocene
and lived roughly 36—2.5 million years ago and existing for approximately .
. The earliest and most primitive borophagine is the genus Archaeocyon
, which is a small fox-sized animal mostly found in the fossil beds in western North America. The borophagines soon diversified into several major groups. They evolved to become considerably larger than their predecessors, and filled a wide range of niches in late Cenozoic
North America, from small omnivore
s to powerful, bear
-sized carnivores such as Epicyon
.
through Blancan
ages. A phylogenetic analysis using cladistic
methods with Hesperocyoninae as an archaic group of canids, as the outgroup. Most of the Borophaginae, aside from some transitional forms, can be organized in four major clades: Phlaocyonini
, Cynarctina
, Aelurodontina, and Borophagina
(all erected from as new tribes or subtribes). The Borophaginae begins with a group of small fox-sized genera, such as Archaeocyon
, Oxetocyon
, Otarocyon
, and Rhizocyon
, in the Orellan
through early Arikareean
stages. These canids reached their maximum diversity of species around 28 million years ago.
Often generically referred to as "bone-crushing dogs" for their powerful teeth and jaws, and hyena
-like features (although their dentition
was more primitive than that of hyenas), their fossil
s are abundant and widespread; in all likelihood, they were probably one of the top predators of their ecosystem
. Their good fossil record has also allowed a detailed reconstruction of their phylogeny, showing that the group was highly diverse in its heyday.
Noteworthy genera in this group are Aelurodon
, Epicyon
, and Borophagus
(=Osteoborus). According to Xiaoming Wang
, the Borophaginae played broad ecological roles that are performed by at least three living carnivoran families, Canidae, Hyaenidae, and Procyonidae
.
(million years=in existence)
Cladogram showing borophagine interrelationships, following Wang et al., figure 141:
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...
during the Oligocene
Oligocene
The Oligocene is a geologic epoch of the Paleogene Period and extends from about 34 million to 23 million years before the present . As with other older geologic periods, the rock beds that define the period are well identified but the exact dates of the start and end of the period are slightly...
to Pliocene
Pliocene
The Pliocene Epoch is the period in the geologic timescale that extends from 5.332 million to 2.588 million years before present. It is the second and youngest epoch of the Neogene Period in the Cenozoic Era. The Pliocene follows the Miocene Epoch and is followed by the Pleistocene Epoch...
and lived roughly 36—2.5 million years ago and existing for approximately .
Origin
The Borophaginae apparently descended from the subfamily HesperocyoninaeHesperocyoninae
Hesperocyoninae is a subfamily of extinct canids.-Taxonomic history:Hesperocyoninae was named by Martin . The members of this subfamily were reassigned to the family Canidae by Xiaoming Wang in 1999....
. The earliest and most primitive borophagine is the genus Archaeocyon
Archaeocyon
Archaeocyon is a small extinct genus of the Borophaginae within the family Canidae which inhabited most of North America during the Whitneyan stage through Geringian stage of the Oligocene epoch 33.3—26.3 Ma Archaeocyon existed for approximately .Species of Archaeocyon are among the earliest...
, which is a small fox-sized animal mostly found in the fossil beds in western North America. The borophagines soon diversified into several major groups. They evolved to become considerably larger than their predecessors, and filled a wide range of niches in late Cenozoic
Cenozoic
The Cenozoic era is the current and most recent of the three Phanerozoic geological eras and covers the period from 65.5 mya to the present. The era began in the wake of the Cretaceous–Tertiary extinction event at the end of the Cretaceous that saw the demise of the last non-avian dinosaurs and...
North America, from small omnivore
Omnivore
Omnivores are species that eat both plants and animals as their primary food source...
s to powerful, bear
Bear
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...
-sized carnivores such as Epicyon
Epicyon
Epicyon is a large extinct canid genus of the subfamily Borophaginae , native to North America. It lived from the Hemingfordian age of the Early Miocene to the Hemphillian of the Late Miocene Epicyon ("near dog") is a large extinct canid genus of the subfamily Borophaginae ("bone-crushing dogs"),...
.
Species
Borophagines are a total of 66 species that includes 18 new species which range from OrellanOrellan
The Orellan 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 33,900,000 to 33,300,000 years BP, a period of . It is usually considered to fall within the Early Oligocene...
through Blancan
Blancan
The Blancan 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 4,750,000 to 1,808,000 years BP, a period of .. It is usually considered to start in the early-mid Pliocene epoch and end...
ages. A phylogenetic analysis using cladistic
Clade
A clade is a group consisting of a species and all its descendants. In the terms of biological systematics, a clade is a single "branch" on the "tree of life". The idea that such a "natural group" of organisms should be grouped together and given a taxonomic name is central to biological...
methods with Hesperocyoninae as an archaic group of canids, as the outgroup. Most of the Borophaginae, aside from some transitional forms, can be organized in four major clades: Phlaocyonini
Phlaocyonini
Phlaocyonini † is a hypocarnivorous clade or tribe of Borophaginae. This is an extinct group of canids that were endemic to North America and which lived during the Oligocene epoch to the Miocene living ~33.3–5.3 Ma, existing for approximately . PhlaocyoniniThe clade includes Cynarctoides and...
, Cynarctina
Cynarctina
Cynarctina is an extinct hypocarnivorous canine sub-tribe clade of Borophaginae . Cynarctina lived during the Hemingfordian stage of Early Miocene through Clarendonian stage of the Middle Miocene 20.6—10.3 Ma, existing for approximately ....
, Aelurodontina, and Borophagina
Borophagina
Borophagina is a hypocarnivorous subfamily or clade of Borophaginae, a group of terrestrial canines which inhabited most of North America during the Hemingfordian stage of the Early Miocene subepoch to the Zanclean stage of the Pliocene epoch 20.6—3.6 Mya existing approximately...
(all erected from as new tribes or subtribes). The Borophaginae begins with a group of small fox-sized genera, such as Archaeocyon
Archaeocyon
Archaeocyon is a small extinct genus of the Borophaginae within the family Canidae which inhabited most of North America during the Whitneyan stage through Geringian stage of the Oligocene epoch 33.3—26.3 Ma Archaeocyon existed for approximately .Species of Archaeocyon are among the earliest...
, Oxetocyon
Oxetocyon
Oxetocyon is an extinct genus of the subfamily Borophaginae and a terrestrial canine which inhabited North America during the Whitneyan stage — of the Oligocene epoch...
, Otarocyon
Otarocyon
Otarocyon is an extinct genus "bone crushing dog" of the family Borophaginae and a terrestrial canine which was small in size endemic to North America during of the Oligocene epoch, ~33.9—20.6 Ma...
, and Rhizocyon
Rhizocyon
Rhizocyon is an early member of the subfamily Borophaginae, an extinct subgroup of canids that were endemic to western North America during the Whitneyan and Arikareean stages) of the Oligocene epoch, living from ~33.3—20.6 Ma., existing for approximately .Rhizocyon was similar to a contemporary...
, in the Orellan
Orellan
The Orellan 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 33,900,000 to 33,300,000 years BP, a period of . It is usually considered to fall within the Early Oligocene...
through early 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...
stages. These canids reached their maximum diversity of species around 28 million years ago.
Often generically referred to as "bone-crushing dogs" for their powerful teeth and jaws, and hyena
Hyena
Hyenas or Hyaenas are the animals of the family Hyaenidae of suborder feliforms of the Carnivora. It is the fourth smallest biological family in the Carnivora , and one of the smallest in the mammalia...
-like features (although their dentition
Dentition
Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, the characteristic arrangement, kind, and number of teeth in a given species at a given age...
was more primitive than that of hyenas), their fossil
Fossil
Fossils are the preserved remains or traces of animals , plants, and other organisms from the remote past...
s are abundant and widespread; in all likelihood, they were probably one of the top predators of their ecosystem
Ecosystem
An ecosystem is a biological environment consisting of all the organisms living in a particular area, as well as all the nonliving , physical components of the environment with which the organisms interact, such as air, soil, water and sunlight....
. Their good fossil record has also allowed a detailed reconstruction of their phylogeny, showing that the group was highly diverse in its heyday.
Noteworthy genera in this group are Aelurodon
Aelurodon
Aelurodon is an extinct canine genus of the subfamily Borophaginae which lived from the Barstovian land mammal age of the middle Miocene to the Clarendonian age of the late Miocene...
, Epicyon
Epicyon
Epicyon is a large extinct canid genus of the subfamily Borophaginae , native to North America. It lived from the Hemingfordian age of the Early Miocene to the Hemphillian of the Late Miocene Epicyon ("near dog") is a large extinct canid genus of the subfamily Borophaginae ("bone-crushing dogs"),...
, and Borophagus
Borophagus
Borophagus is an extinct genus of the subfamily Borophaginae, a group of canids endemic to North America from the early Miocene epoch through the Zanclean stage of the Pliocene epoch 23.3—3.6 Mya. Borophagus existed for approximately .-Overview:Borophagus, like other borophagines, are loosely...
(=Osteoborus). According to Xiaoming Wang
Xiaoming Wang
Xiaoming Wang is a noted paleontologist and geologist born in People's Republic of China living in the United States.-Area of expertise:Dr. Wang specializes in the fossil evolution, systematics, and phylogeny of mammals of the Cenozoic...
, the Borophaginae played broad ecological roles that are performed by at least three living carnivoran families, Canidae, Hyaenidae, and Procyonidae
Procyonidae
Procyonidae is a New World family of the order Carnivora. It includes the raccoons, coatis, kinkajous, olingos, ringtails and cacomistles. Procyonids inhabit a wide range of environments, and are generally omnivorous.-Characteristics:...
.
Classification
Borophagine taxonomy, following Wang et al.- Family CanidaeCanidaeCanidae is the biological family of carnivorous and omnivorous mammals that includes wolves, foxes, jackals, coyotes, and domestic dogs. A member of this family is called a canid . The Canidae family is divided into two tribes: Canini and Vulpini...
(million years=in existence)
-
- Subfamily †Borophaginae
- †ArchaeocyonArchaeocyonArchaeocyon is a small extinct genus of the Borophaginae within the family Canidae which inhabited most of North America during the Whitneyan stage through Geringian stage of the Oligocene epoch 33.3—26.3 Ma Archaeocyon existed for approximately .Species of Archaeocyon are among the earliest...
33—26 Ma, existing - †OxetocyonOxetocyonOxetocyon is an extinct genus of the subfamily Borophaginae and a terrestrial canine which inhabited North America during the Whitneyan stage — of the Oligocene epoch...
33—28 Ma, existing - †OtarocyonOtarocyonOtarocyon is an extinct genus "bone crushing dog" of the family Borophaginae and a terrestrial canine which was small in size endemic to North America during of the Oligocene epoch, ~33.9—20.6 Ma...
34—30 Ma, existing - †RhizocyonRhizocyonRhizocyon is an early member of the subfamily Borophaginae, an extinct subgroup of canids that were endemic to western North America during the Whitneyan and Arikareean stages) of the Oligocene epoch, living from ~33.3—20.6 Ma., existing for approximately .Rhizocyon was similar to a contemporary...
33—26 Ma, existing - Tribe †PhlaocyoniniPhlaocyoniniPhlaocyonini † is a hypocarnivorous clade or tribe of Borophaginae. This is an extinct group of canids that were endemic to North America and which lived during the Oligocene epoch to the Miocene living ~33.3–5.3 Ma, existing for approximately . PhlaocyoniniThe clade includes Cynarctoides and...
33—13 Ma, existing- †CynarctoidesCynarctoidesCynarctoides is an extinct genus of terrestrial canine of the family Borophaginae and tribe Phlaocyonini which inhabited most of North America during the Whitneyan stage of the Early Oligocene to the Barstovian stage of the Middle Miocene 33.3—13.6 Mya existing approximately .-Origin:Cynarctoides...
30—18 Ma, existing - †PhlaocyonPhlaocyonPhlaocyon is an extinct genus of the Borophaginae and a terrestrial canine which inhabited most of North America during the Whitneyan stage of the Early Oligocene through Late Hemingfordian stage of the Early Miocene epoch 33.3—16.3 Mya existing for approximately .-Taxonomy:Phlaocyon was about in...
30—19 Ma,
- †Cynarctoides
- Tribe †BorophaginiBorophaginiBorophagini is a clade or tribe of the subfamily Borophaginae. This is an extinct group of terrestrial canids that were endemic and widespread throughout North America and Central America which lived during the Geringian stage of the Oligocene epoch to the Zanclean age of the Early Pliocene living...
30—3 Ma, existing- †CormocyonCormocyonCormocyon is an extinct genus of the Borophaginae and a terrestrial canine which inhabited most of North America during the Geringian stage of the Paleogene through Harrisonian stage of the Oligocene epoch living 30.8—20.6 Mya, existing for about ....
30—20 Ma, existing - †DesmocyonDesmocyonDesmocyon is an extinct genus of the Borophaginae and a terrestrial canine which inhabited most of North America during the Harrisonian stage of the Late Oligocene through Early Hemingfordian stage of the Early Miocene epoch living 24.8—16.3 Mya existing for approximately .-Fossil record:It is a...
25—16 Ma, existing - †MetatomarctusMetatomarctusMetatomarctus is an extinct genus of Borophaginae and a terrestrial canine which inhabited most of North America during the Early Hemingfordian stage of the Miocene epoch living 23.0—5.3 Mya, existing for approximately -Taxonomy:...
19—16 Ma, existing - †EuoplocyonEuoplocyonEuoplocyon is an extinct genus of the Borophaginae and a small terrestrial canine which inhabited most of North America during the Hemingfordian stage of the Early Miocene subepoch through the Barstovian stage of the Middle Miocene subepoch living 20.6—13.6 Mya, existing for about...
18—16 Ma, existing ) - †PsalidocyonPsalidocyonPsalidocyon is an extinct genus of the Borophaginae and a small terrestrial canine which inhabited most of North America during the Hemingfordian stage of the Early Miocene subepoch through the Barstovian stage of the Middle Miocene subepoch 20.6—13.6 Ma, existing for about ..-Morphology:Fossil...
16—13 Ma, existing - †MicrotomarctusMicrotomarctusMicrotomarctus is an extinct genus of the Borophaginae and a small terrestrial canine which inhabited most of North America during the Whitneyan stage of the Early Miocene subepoch through the Barstovian stage of the Middle Miocene subepoch.Microtomarctus existed for approximately .Like other...
21—13 Ma, existing ( - †ProtomarctusProtomarctusProtomarctus is an extinct member of the Borophaginae and a small terrestrial canine which inhabited most of North America during the Burdigalian stage of the Miocene epoch 20.4—15.9 Mya, existing for approximately .-Taxonomy:...
20—16 Ma, existing ( - †TephrocyonTephrocyonTephrocyon is an extinct genus of the Borophaginae and a small to medium sized terrestrial canine which inhabited most of North America during the Barstovian stage of the Middle Miocene 16.3—13.6 Ma, existing for approximately .-Morphology:...
16—14 Ma, existing - Subtribe †CynarctinaCynarctinaCynarctina is an extinct hypocarnivorous canine sub-tribe clade of Borophaginae . Cynarctina lived during the Hemingfordian stage of Early Miocene through Clarendonian stage of the Middle Miocene 20.6—10.3 Ma, existing for approximately ....
20—10 Ma, existing- †ParacynarctusParacynarctusParacynarctus is an extinct genus of the Borophaginae and a terrestrial canine which inhabited most of North America during the Early Hemingfordian stage of the Early Miocene subepoch through the Early Barstovian stage of the Middle Miocene subepoch 20.6—13.6 Ma, existing for approximately .As...
19—16 Ma, existing - †CynarctusCynarctusCynarctus is an extinct canid of the subfamily Borophaginae which inhabited most of North America during the Late Miocene subepoch . Cynarctus existed for approximately .-Taxonomy:...
16—12 Ma, existing
- †Paracynarctus
- Subtribe †Aelurodontina 20—5 Ma, existing
- †TomarctusTomarctusTomarctus is a canine of the extinct subfamily Borophaginae which inhabited most of North America during the late Early Miocene to the Early Barstovian age of the Middle Miocene . Tomarctus existed for approximately ....
23—16 Ma, existing - †AelurodonAelurodonAelurodon is an extinct canine genus of the subfamily Borophaginae which lived from the Barstovian land mammal age of the middle Miocene to the Clarendonian age of the late Miocene...
16—12 Ma, existing
- †Tomarctus
- Subtribe †BorophaginaBorophaginaBorophagina is a hypocarnivorous subfamily or clade of Borophaginae, a group of terrestrial canines which inhabited most of North America during the Hemingfordian stage of the Early Miocene subepoch to the Zanclean stage of the Pliocene epoch 20.6—3.6 Mya existing approximately...
- †ParatomarctusParatomarctusParatomarctus an extinct member of the Borophaginae, subtribe Borophagina, a terrestrial canine which inhabited most of North America from the Harrisonian stage to Early Barstovian stage of the Miocene epoch living 16.3—5.3 mya, existed for approximately .-Canid competitors:Paratomarctus was one...
16—5 Ma, existing - †CarpocyonCarpocyonCarpocyon is an extinct member of the Borophaginae, and a terrestrial canine which inhabited most of North America during the Barstovian stage of the Middle Miocene through the Hemphillian stage of the Late Miocene epoch 20.4—3.9 Mya. Carpocyon existed for approximately .-Taxonomy:Carpocyon was...
16—5 Ma, existing - †ProtepicyonProtepicyonProtepicyon is an extinct genus of the family Borophaginae which lived during the Barstovian stage of the Middle Miocene subepoch living 16.3—13.6 mya, existing for approximately ....
16—12 Ma, existing - †EpicyonEpicyonEpicyon is a large extinct canid genus of the subfamily Borophaginae , native to North America. It lived from the Hemingfordian age of the Early Miocene to the Hemphillian of the Late Miocene Epicyon ("near dog") is a large extinct canid genus of the subfamily Borophaginae ("bone-crushing dogs"),...
12—10 Ma, existing - †BorophagusBorophagusBorophagus is an extinct genus of the subfamily Borophaginae, a group of canids endemic to North America from the early Miocene epoch through the Zanclean stage of the Pliocene epoch 23.3—3.6 Mya. Borophagus existed for approximately .-Overview:Borophagus, like other borophagines, are loosely...
(=Osteoborus) 12—5 Ma, existing (
- †Paratomarctus
- †Cormocyon
- †Archaeocyon
- Subfamily †Borophaginae
Cladogram showing borophagine interrelationships, following Wang et al., figure 141:
Additional Reading
- Xiaoming Wang, Richard H. Tedford, Mauricio Antón, Dogs: Their Fossil Relatives and Evolutionary History, New York : Columbia University Press, 2008; ISBN 978-0-231-13528-3