Carnivoramorpha
Encyclopedia
Carnivoramorpha are a clade
of mammals that includes the modern order Carnivora
and its closest extinct relatives in the Miacoidea
(Miacidae and Viverravidae), but excludes the creodonts. The order Creodonta are a sister taxon
to the Carnivoramorpha dating back 58.7 million years ago. The oldest carnivoramorphans are viverravids, and the oldest generally accepted viverravid is Protictis dated at 63 million years ago. Ravenictis from Canada may also be a carnivoramorphan and this would extend the date back to at least 65 million years ago.
(P4) and lower first molar
(m1) as carnassial
teeth has been considered a synapomorphy
for carnivorans, here we follow a recent convention employing the name Carnivoramorpha for that clade and restricting the meaning of the widely known name Carnivora to the smaller crown clade delimited by the extant species
regarded as carnivorans. Accordingly, Carnivoramorpha is here defined as the smallest clade containing the earliest organism to have the P4/m1 carnassial shear synapomorphic with that in Felis catus. Morphological and molecular evidence indicates that the carnivoran Aeluroid, Cynoid and Arctoid clades share an exclusive common ancestry. Species representing these three major carnivoran clades are used as specifiers in the definition of Carnivora, which is here defined as the smallest clade containing Felis catus, Canis familiaris and Mustela erminea.”
they were not the only group of terrestrial
meat-eating mammals present. The Creodonta, composed of the Oxyaenids (robust, short-limbed wolverine forms) and the Hyaenodontids (slender-limbed, semi-cursorial
forms), were also present and were well on their way toward their maximum speciation, which occurred in the middle Eocene
era (Stiles, 2005). Judging from their dentition
s, many were specialized meat eaters and must be included in any study addressing the evolution of mammalian carnivory
. In North America few creodonts survived past the Eocene
, and all were extinct by the late Oligocene
. The taxonomic decline of Creodonta at the end of the Eocene coincided with the beginning of the speciation and radiation of the Carnivora, and the origination of most modern carnivore families. Regardless of whether this was taxonomic displacement or replacement this pattern has generated the hypothesis that the diversification of carnivorans was suppressed by the incumbent creodonts early in their history.
The first carnivores likely arose from a small insectivorous mammal found in the middle Eocene era, a time of rapid differentiation for mammalian species. The earliest known members of the carnivores are rarely found as fossilized bones; most often they are recovered strictly as tooth samples and partial jaw fragments. These pioneering species are classified in the Miacidae clade, which is morphologically separable into two lineages, the Viverravines and the Miacines. Both members of these lineages display dental features that are typically characteristic of carnivores, shearing teeth known as carnassials along with the presence of a transverse
jaw hinge. The main difference in these early Miacidae members is found in their dentition, the Miacines resemble the caniforms
while the Viverravines resemble the feliforms
.
Carnivoramorpha
|?- †Aelurotherium
|?- †Eosictis
|?- †Elmensius
|?- †Intyrictis vanvaleni
|?- †Notoamphicyon
|?- †Ravenictis krausei or cimolestan
|?- †Vishnucyon
`--+-- †Miacoidea (paraphyletic)
`--+-- †Viverravidae [Viverraroidea]
`--+-- †Miacidea (paraphyletic)
`--+-- †Oodectes
`--+-- †Vulpavus
`--+-- †Miacis
`--+--+-- †Tapocyon
| `--+-- †Miacis sylvestris
| `-- †Prohesperocyon wilsoni
`--+-- †Quergygale angustidens
`-- †Nimravidae? (very unstable position with respect to Carnivora -
unresolved as of August 2007)
`-- Carnivora
`-- Caniformia
`-- Aeluroidea
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...
of mammals that includes the modern order Carnivora
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...
and its closest extinct relatives in the Miacoidea
Miacoidea
Miacoidea is paraphyletic superfamily that had been traditionally divided into two families of carnivores: Miacidae and Viverravidae. Miacoids were primitive carnivores which lived during the Paleocene and Eocene Epoch about 33-65 million years ago...
(Miacidae and Viverravidae), but excludes the creodonts. The order Creodonta are a sister taxon
Taxon
|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...
to the Carnivoramorpha dating back 58.7 million years ago. The oldest carnivoramorphans are viverravids, and the oldest generally accepted viverravid is Protictis dated at 63 million years ago. Ravenictis from Canada may also be a carnivoramorphan and this would extend the date back to at least 65 million years ago.
Definition
The First International Phylogenetic Nomenclature Meeting (2004) states: “Modification of the upper fourth premolarPremolar
The premolar teeth or bicuspids are transitional teeth located between the canine and molar teeth. In humans, there are two premolars per quadrant, making eight premolars total in the mouth. They have at least two cusps. Premolars can be considered as a 'transitional tooth' during chewing, or...
(P4) and lower first molar
Molar (tooth)
Molars are the rearmost and most complicated kind of tooth in most mammals. In many mammals they grind food; hence the Latin name mola, "millstone"....
(m1) as carnassial
Carnassial
Carnassials are large teeth found in many carnivorous mammals, used for shearing flesh and bone in a scissor- or shear-like way. In the Carnivora, the carnassials are the modified last upper premolar and the first molar, but in the prehistoric creodonts, the carnassials were further back in the...
teeth has been considered a synapomorphy
Synapomorphy
In cladistics, a synapomorphy or synapomorphic character is a trait that is shared by two or more taxa and their most recent common ancestor, whose ancestor in turn does not possess the trait. A synapomorphy is thus an apomorphy visible in multiple taxa, where the trait in question originates in...
for carnivorans, here we follow a recent convention employing the name Carnivoramorpha for that clade and restricting the meaning of the widely known name Carnivora to the smaller crown clade delimited by the extant species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
regarded as carnivorans. Accordingly, Carnivoramorpha is here defined as the smallest clade containing the earliest organism to have the P4/m1 carnassial shear synapomorphic with that in Felis catus. Morphological and molecular evidence indicates that the carnivoran Aeluroid, Cynoid and Arctoid clades share an exclusive common ancestry. Species representing these three major carnivoran clades are used as specifiers in the definition of Carnivora, which is here defined as the smallest clade containing Felis catus, Canis familiaris and Mustela erminea.”
Evolution
When Carnivoramorpha first emerged in the PaleocenePaleocene
The Paleocene or Palaeocene, the "early recent", is a geologic epoch that lasted from about . It is the first epoch of the Palaeogene Period in the modern Cenozoic Era...
they were not the only group 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...
meat-eating mammals present. The Creodonta, composed of the Oxyaenids (robust, short-limbed wolverine forms) and the Hyaenodontids (slender-limbed, semi-cursorial
Cursorial
Cursorial is a biological term that describes an organism as being adapted specifically to run. It is typically used in conjunction with an animal's feeding habits or another important adaptation. For example, a horse can be considered a "cursorial grazer", while a wolf may be considered a...
forms), were also present and were well on their way toward their maximum speciation, which occurred in the middle Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
era (Stiles, 2005). Judging from 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...
s, many were specialized meat eaters and must be included in any study addressing the evolution of mammalian carnivory
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...
. In North America few creodonts survived past the Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
, and all were extinct by the late 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...
. The taxonomic decline of Creodonta at the end of the Eocene coincided with the beginning of the speciation and radiation of the Carnivora, and the origination of most modern carnivore families. Regardless of whether this was taxonomic displacement or replacement this pattern has generated the hypothesis that the diversification of carnivorans was suppressed by the incumbent creodonts early in their history.
The first carnivores likely arose from a small insectivorous mammal found in the middle Eocene era, a time of rapid differentiation for mammalian species. The earliest known members of the carnivores are rarely found as fossilized bones; most often they are recovered strictly as tooth samples and partial jaw fragments. These pioneering species are classified in the Miacidae clade, which is morphologically separable into two lineages, the Viverravines and the Miacines. Both members of these lineages display dental features that are typically characteristic of carnivores, shearing teeth known as carnassials along with the presence of a transverse
Transverse plane
The transverse plane is an imaginary plane that divides the body into superior and inferior parts. It is perpendicular to the coronal and sagittal planes....
jaw hinge. The main difference in these early Miacidae members is found in their dentition, the Miacines resemble the caniforms
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...
while the Viverravines resemble the feliforms
Feliformia
The Feliformia are a suborder within the order Carnivora and includes cats , hyenas, mongooses, civets and related taxa. The other suborder of Carnivora is Caniformia...
.
Classification & Phylogeny
- Clade Carnivoramorpha (basalBasal (phylogenetics)In phylogenetics, a basal clade is the earliest clade to branch in a larger clade; it appears at the base of a cladogram.A basal group forms an outgroup to the rest of the clade, such as in the following example:...
to Carnivora but without Creodonts)- Superfamily †MiacoideaMiacoideaMiacoidea is paraphyletic superfamily that had been traditionally divided into two families of carnivores: Miacidae and Viverravidae. Miacoids were primitive carnivores which lived during the Paleocene and Eocene Epoch about 33-65 million years ago...
- Family †Miacidae
- genera: ChailicyonChailicyonChailicyon is an extinct genus of canidae, suborder Caniformia.-Sources:**The Terrestrial Eocene-Oligocene Transition in North America by Donald R. Prothero and Robert J. Emry ISBN 0521433878...
, Eostictis, IctognathusIctognathusIctognathus is an extinct genus of Miacidae....
, MiacisMiacisThe 'genus' Miacis contains extinct species of carnivorous mammals that appeared in the late Paleocene and continued through the Eocene. The genus Miacis is not monophyletic but a diverse collection of species that belong to the stemgroup within the Carnivoramorpha...
, MiocyonMiocyonMiocyon is an extinct genus of Miacidae, primitive carnivores which lived during the Paleocene and Eocene Epoch.-References:* Flynn, J.J., 1998. Early Cenozoic Carnivora . pp.110-123 in C.M. Janis, K.M. Scott, and L.L. Jacobs Evolution of Tertiary Mammals of North America...
, OodectesOödectesOodectes is an extinct genus of Miacidae.-Sources:**Fossil Mammalia of the Huerfano Formation, Eocene, of Colorado by Peter Robinson**...
, PalaearctonyxPalaearctonyxPalaearctonyx is an extinct genus of omnivorous Miacidae which inhabited North America during the Eocene living from 50.3—46.2 Ma and existed for approximately .-Taxonomy:Palaearctonyx was named by Matthew . Its type is Palaearctonyx meadi...
, ParamiacisParamiacisParamiacis is an extinct genus of Miacidae. Christian Mathis has defined to make a difference between the miacidae from Europe and the American genus Miacis. There are two species of it, P. exilis and P...
, ParoodectesParoodectesParoodectes was a miacid animal that lived during the early Eocene in the rain forests and swamps of the present-day Germany. It was a prehistoric predator that had the size and the appearance of a cat and was well adapted to climbing, as is apparent from its limbs, joints and shoulder bones...
, Prodaphaemus, Quercgyale, TapocyonTapocyonTapocyon is an extinct genus of Miacidae, a family of primitive carnivores. Tapocyon was first discovered in Ventura County, when part of a jaw was found in the 1930's. A representative fossil of Tapocyon robustus was found in Oceanside, California...
, UintacyonUintacyonUintacyon is an extinct genus of Miacidae. There are at least two species in the genus; Uintacyon rudis and Uintacyon gingerichi, the latter being recently discovered.-Sources:...
, VassacyonVassacyonVassacyon is an extinct genus of Miacidae. It contains two species; Vassacyon promicrodon and Vassacyon bowni. It is considered the largest of the early Eocene mammals.-References:...
, VulpavusVulpavusVulpavus is an extinct genus of Miacidae.-References:* Alexander, J. 1992. Alas poor Notharctus. Natural History 9:54-59.* Flynn, J.J., 1998. Early Cenozoic Carnivora . pp.110-123 in C.M. Janis, K.M. Scott, and L.L. Jacobs Evolution of Tertiary Mammals of North America...
, XinyuictisXinyuictisXinyuictis is an extinct genus of Miacidae. It contains a species, Xinyuictis tenuis. It was once suggested that the species was the same as Miacis, but it was eventually decided that they were different.-Sources:...
, ZiphacodonZiphacodonZiphacodon is an extinct genus of Miacidae. The species Ziphacodon rugatus was described as a new species by M. R. Thorpe in 1923. The genus itself was first described by Marsh in 1872.-Sources:...
- genera: Chailicyon
- Family †Viverravidae
- genera: BryanictisBryanictisBryanictis is an extinct genus of Viverravidae. It was named by MacIntyre in 1966. Species of Bryanictis include Bryanictis microlestes and Bryanictis paulus.-Sources:...
, DidymictisDidymictisDidymictis is an extinct genus of Viverravidae. It contains six species; Didymictis altidens, Didymictis leptomylus, Didymictis lysitensis, Didymictis protenus, Didymictis proteus, and Didymictis vancleveae.-Sources:...
, IctidopappusIctidopappusIctidopappus is an extinct genus of Viverravidae. The genus contains at least one species; Ictidopappus mustelinus. It was first described by Simpson in 1935.-Sources:**...
, MustelodonMustelodonMustelodon is an extinct carnivore, which belongs to the family Viverravidae. This genus contains only one species, Mustelodon primerus...
, PristinictisPristinictisPristinictis is an extinct genus of Viverravidae, and is considered a primitive member of the group. It was first named by Fox and Youzwyshyn in 1994. It contains at least one species, Pristinictis connata.-Sources:***...
, Protictis, RaphictisRaphictisRaphictis is an extinct genus of Didymictidae. It was first named by P. D. Gingerich and D. A. Winkler in 1985, and contains one species: R. gausion.-References:...
, Simpsonictis, Viverravus
- genera: Bryanictis
- Family †Miacidae
- Order CarnivoraCarnivoraThe 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...
- Superfamily CaniformiaCaniformiaCaniformia, 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...
or Canoidea - Superfamily FeliformiaFeliformiaThe Feliformia are a suborder within the order Carnivora and includes cats , hyenas, mongooses, civets and related taxa. The other suborder of Carnivora is Caniformia...
or Feloidea
- Superfamily Caniformia
- Superfamily †Miacoidea
Carnivoramorpha
|?- †Aelurotherium
|?- †Eosictis
|?- †Elmensius
|?- †Intyrictis vanvaleni
|?- †Notoamphicyon
|?- †Ravenictis krausei or cimolestan
|?- †Vishnucyon
`--+-- †Miacoidea (paraphyletic)
`--+-- †Viverravidae [Viverraroidea]
`--+-- †Miacidea (paraphyletic)
`--+-- †Oodectes
`--+-- †Vulpavus
`--+-- †Miacis
`--+--+-- †Tapocyon
| `--+-- †Miacis sylvestris
| `-- †Prohesperocyon wilsoni
`--+-- †Quergygale angustidens
`-- †Nimravidae? (very unstable position with respect to Carnivora -
unresolved as of August 2007)
`-- Carnivora
`-- Caniformia
`-- Aeluroidea