{{Short description|Suborder of mammals}} {{Automatic taxobox | name = Caniforms | fossil_range = {{Fossil range|43|0}} <small>Eocene-Holocene</small> | image = Caniformia 2021 Montage.jpg | image_upright = 1.2 | image_caption = All extant caniform families ''(from left to right)'': Canidae, Ursidae, Procyonidae, Mephitidae, Ailuridae, Mustelidae, Otariidae, Odobenidae, Phocidae | taxon = Caniformia | authority = Kretzoi, 1943 | subdivision_ranks = Subgroups | subdivision = * Arctoidea * Cynoidea * †Amphicyonidae * ''Incertae sedis'' ** †''Lonchocyon'' ** †''Lycophocyon'' }}
'''Caniformia''' is a suborder within the order Carnivora consisting of "dog-like" carnivorans. They include dogs (wolves, foxes, etc.), bears, raccoons, mustelids,<ref>{{Cite web | author= Basic Biology | date= 2015 | title= Carnivora | url= https://basicbiology.net/animal/mammals/carnivora}}</ref> and pinnipeds (seals, walruses and sea lions). The center of diversification for the Caniformia is North America and northern Eurasia. Caniformia stands in contrast to the other suborder of Carnivora, the Feliformia ("cat-like" carnivorans), the center of diversification of which was in Africa and southern Asia.
==Description== Most members of this group have nonretractile claws (the fisher,<ref>{{cite web | last = Rhines | first = C | year = 2003 | title = Martes pennanti | work = Animal Diversity Web | access-date = March 12, 2011 | url = http://animaldiversity.ummz.umich.edu/site/accounts/information/Martes_pennanti.html }}</ref> marten,<ref>{{cite web | title = American Marten | publisher = New York State Department of Environmental Conservation | url = http://www.dec.ny.gov/animals/45531.html | access-date = March 12, 2011 }}</ref> sea otter (forepaws only),<ref>Silverstein, Alvin; Silverstein, Virginia and Robert (1995). The Sea Otter. Brookfield, Connecticut: The Millbrook Press, Inc. {{ISBN|978-1-56294-418-6}}. OCLC 30436543. p11. </ref> red panda,<ref>{{cite journal | last1 = Roberts | first1 = M. S. | last2 = Gittleman | first2 = J. L. | title = Ailurus fulgens | journal = Mammalian Species | year = 1984 | issue = 222 | page = 3 | publisher = The American Society of Mammalogists | url = http://si-pddr.si.edu/dspace/bitstream/10088/4231/1/Roberts1984.pdf | access-date = March 12, 2011 | doi = 10.2307/3503840 | jstor = 3503840 | bibcode = 1984MamSp.222....1R | s2cid = 253993605 | archive-date = May 15, 2013 | archive-url = https://web.archive.org/web/20130515022125/http://si-pddr.si.edu/dspace/bitstream/10088/4231/1/Roberts1984.pdf }}</ref> and ringtail, and some foxes have retractile or semi-retractile claws<ref>{{cite web | last = Goldberg | first = J. | title = Bassariscus astutus | work = Animal Diversity Web | year = 2003 | url = http://animaldiversity.ummz.umich.edu/site/accounts/information/Bassariscus_astutus.html | access-date = March 12, 2011 }}</ref>) and tend to be plantigrade (with the exception of the Canidae). Other traits that separate the Caniformia from the Feliformia is that caniforms have longer jaws and more teeth, with less specialized carnassial teeth. They also tend more towards omnivory and opportunistic feeding, while the feliforms, other than the viverrids, are more specialized for eating meat. Caniforms have single-chambered or partially divided auditory bullae, composed of a single bone, while in feliforms, the auditory bullae are double-chambered, composed of two bones joined by a septum.<ref name="Ewer1973">{{cite book|author=R. F. Ewer|title=The Carnivores|url=https://books.google.com/books?id=IETMd3-lSlkC|access-date=9 January 2013|year=1973|publisher=Cornell University Press|isbn=978-0-8014-8493-3}}</ref> In the Caniformia, the bulbourethral glands and vesicula seminalis are always absent. Relative to body size, the baculum is usually longer in the Caniformia than in the Feliformia.<ref name="Ewer1973" />
== Extant families == [[File:Polar-bear-arctic-wildlife-snow-53425.jpg|thumb|Polar bear, the largest terrestrial caniform]] [[image:Alaska Weasel.jpg|thumb| The smallest caniform is the least weasel.]]
Caniformia consists of nine extant families, with three extinct families also recognized. The extant families are monophyletic according to phylogenetic molecular analysis.<ref>{{cite journal |author1=Eizirik E. |author2=Murphy W.J. |author3=Koepfli K.P. |author4=Johnson W.E. |author5=Dragoo J.W. |author6=O'Brien S.J. | year = 2010 | title = Pattern and timing of the diversification of the mammalian order Carnivora inferred from multiple nuclear gene sequences | journal = Molecular Phylogenetics and Evolution | volume = 56 | issue = 1| pages = 49–63 | doi = 10.1016/j.ympev.2010.01.033 | pmid=20138220| pmc = 7034395 |bibcode=2010MolPE..56...49E }}</ref> Terrestrial caniforms in the wild are found on all continents with the exception of Antarctica, while pinnipeds are distributed throughout the world's oceans.
Family Canidae (dogs and other canids) includes wolves, dogs, coyotes, and foxes, as well as a number of less familiar animals. The family is currently divided into two major groups, the true dogs (tribe Canini), which includes nine genera, and the true foxes (tribe Vulpini) with two genera. In addition, two basal genera are described. About 35 species of extant canids are currently recognized. Canids are the most social of all caniforms, sometimes living in packs. The dog is the most diverse of all mammals in terms of body structure variants.{{Citation needed|date=January 2015}}
Family Ursidae (bears) is the largest of all the land caniforms. Eight species are recognized, divided into five genera. They range from the large polar bear ({{convert|350|–|680|kg|lb}} in males) to the small sun bear ({{convert|30|–|60|kg|lb}} in males) and from the endangered giant panda to the very common black bear. Common characteristics of modern bears include a large body with stocky legs, a long snout, shaggy hair, plantigrade paws with five nonretractile claws, and a short tail. Most bears are omnivorous, with largely varied diets that include both plants and animals. The polar bear is the most carnivorous of bears due to the arctic climate in which it lives, and shows a preference for eating seals. The giant panda is the most herbivorous bear and has evolved a number of adaptations, including a sixth "toe", specialized teeth, and strong jaw muscles, to allow it to feed nearly exclusively on bamboo, a tough member of the grass family. The sloth bear has some adaptations for ant and termite eating, with a long snout, powerful claws, and missing upper front teeth, though it also eats honey and fruit.
Family Ailuridae consists today of a single species, the red panda, which was once thought to be included in the Procyonidae or Ursidae lineages, but is now placed in its own family along with a number of extinct species. It is found in the Himalayas, including southern China, Nepal, Bhutan, India, and Pakistan. Fossil species of the family are also found in North America.<ref>{{cite web|url=http://www.nhm.org/expeditions/rrc/wang/documents/WallaceandWang2004Nature_000.pdf |title=Two new carnivores from an unusual late Tertiary forest biota in eastern North America |access-date=2007-02-27 |archive-url=https://web.archive.org/web/20070930024527/http://www.nhm.org/expeditions/rrc/wang/documents/WallaceandWang2004Nature_000.pdf |archive-date=2007-09-30 }}</ref>
Family Mephitidae (skunks and stink badgers) was once classified as mustelids, but are now recognized as a lineage in their own right. The 12 species of skunks are divided into four genera: ''Mephitis'' (hooded and striped skunks, two species), ''Spilogale'' (spotted skunks, four species), ''Mydaus'' (stink badgers, two species) and ''Conepatus'' (hog-nosed skunks, four species). The two skunk species in the genus ''Mydaus'' inhabit Indonesia and the Philippines; all other skunks inhabit the Americas from Canada to central South America.
Family Mustelidae (badgers, weasels and otters) is the largest family of carnivora, with 22 extant genera and roughly 57 extant species. While highly variable in shape, size, and behavior, most mustelids are smaller animals with short legs, short, round ears, and thick fur. Mustelids are predominantly carnivorous. While not all share identical dentition, they all possess teeth adapted for eating flesh, including the presence of shearing carnassials.
Members of Family Procyonidae (raccoons, coatis) are smallish animals, with generally slender bodies and long tails. Nineteen extant species in six genera are currently recognized. Except for the kinkajou, all procyonids have banded tails and distinct facial markings, and like bears, are plantigrade, walking on the soles of their feet. Most species have nonretractile claws. Early procyonids may have been an offshoot of the canids that adapted to more omnivorous diets.<ref name=EoM>{{cite book|editor= Macdonald, D.|author= Russell, James|year= 1984|title= The Encyclopedia of Mammals|publisher= Facts on File|location= New York|pages= [https://archive.org/details/encyclopediaofma00mals_0/page/98 98–99]|isbn= 0-87196-871-1|url-access= registration|url= https://archive.org/details/encyclopediaofma00mals_0/page/98}}</ref>
Pinnipedia (seals, sea lions, and walruses clade) is a widely distributed and diverse group of semiaquatic marine mammals which is closely related to an extinct group of pinnipeds, ''Enaliarctos''. While support for the monophyly of pinnipeds is strong, the relationship of pinnipeds to terrestrial mammals is still unclear. Some studies support the hypothesis that the bears are their closest relatives,<ref>{{cite journal |author1=Lento, G. M. |author2=Hickson, R. E. |author3=Chambers, G. K. |author4=Penny, D. |year=1995 |title=Use of spectral analysis to test hypotheses on the origin of pinnipeds |journal=Molecular Biology and Evolution |volume=12 |issue=1 |pages=28–52 |pmid=7877495 |doi=10.1093/oxfordjournals.molbev.a040189|doi-access= }}</ref><ref>{{cite journal|author1=Hunt, R. M. Jr.|author2=Barnes, L. G.|year=1994|title=Basicranial evidence for ursid affinity of the oldest pinnipeds|journal=Proceedings of the San Diego Society of Natural History|volume=29|pages=57–67|url=https://archive.org/details/cbarchive_36692_basicranialevidenceforursidaff1990}}</ref><ref name="Higdon 2007">{{Cite journal |author1=Higdon, J. W. |author2=Bininda-Emonds, O. R. |author3=Beck, R. M. |author4=Ferguson, S. H. |title=Phylogeny and divergence of the pinnipeds (Carnivora: Mammalia) assessed using a multigene dataset |doi=10.1186/1471-2148-7-216 |journal=BMC Evolutionary Biology |volume=7 |page=216 |year=2007 |issue=1 |pmid=17996107 |pmc=2245807 |bibcode=2007BMCEE...7..216H |doi-access=free }}</ref> while others support a closer relationship to the mustelids.<ref name=Sato>{{Cite journal |author1=Sato, J. J. |author2=Wolsan, M. |author3=Suzuki, H. |author4=Hosoda, T. |author5=Yamaguchi, Y. |author6=Hiyama, K. |author7=Kobayashi, M. |author8=Minami, S. |doi=10.2108/zsj.23.125 |title=Evidence from nuclear DNA sequences sheds light on the phylogenetic relationships of Pinnipedia: Single origin with affinity to Musteloidea |journal=Zoological Science |volume=23 |issue=2 |pages=125–46 |year=2006 |pmid=16603806|bibcode=2006ZooS...23..125S |hdl=2115/13508 |s2cid=25795496 |hdl-access=free }}</ref><ref name="Flynn2005">{{Cite journal |author1=Flynn, J. J. |author2=Finarelli, J. A. |author3=Zehr, S. |author4=Hsu, J. |author5=Nedbal, M. A. |title=Molecular phylogeny of the Carnivora (Mammalia): Assessing the impact of increased sampling on resolving enigmatic relationships |doi=10.1080/10635150590923326 |journal=Systematic Biology |volume=54 |issue=2 |pages=317–37 |year=2005 |pmid=16012099|doi-access=free }}</ref><ref name=leptin>{{cite journal|author=Hammond, J. A. |author2=Hauton, C. |author3=Bennett, K. A. |author4=Hall, A. J.|year=2012|title=Phocid seal leptin: Tertiary structure and hydrophobic receptor binding site preservation during distinct leptin gene evolution|journal=PLOS ONE|volume=7|issue=4|article-number=e35395|doi=10.1371/journal.pone.0035395|editor1-last=Nikolaidis|editor1-first=Nikolas |pmid=22536379 |pmc=3334926|bibcode=2012PLoSO...735395H |doi-access=free }}</ref><ref name="Dawson2009">{{Cite journal |author1=Rybczynski, N. |author2=Dawson, M. R. |author3=Tedford, R. H. |doi=10.1038/nature07985 |title=A semi-aquatic Arctic mammalian carnivore from the Miocene epoch and origin of Pinnipedia |journal=Nature |volume=458 |issue=7241 |pages=1021–24 |year=2009 |pmid=19396145|bibcode=2009Natur.458.1021R |s2cid=4371413 }}</ref>
Pinnipeds split from other caniforms 50 million years ago (Mya) during the Eocene.<ref name=leptin/>
The clade is currently divided into three families:
:Family Phocidae (true or earless seals) consists of around 19 species of highly aquatic, barrel-shaped animals ranging from {{convert|45|kg|abbr=on|sigfig=1}} and {{convert|1.2|m|ft|0|abbr=on}} in length (the ringed seal), to {{convert|2400|kg|abbr=on}} and {{convert|5|m|abbr=on}} (southern elephant seal). Phocids are found throughout the world's oceans.
:Family Otariidae (eared seals, sea lions, fur seals) is distributed throughout the world's oceans with the exception of the North Atlantic. The 15 species (divided into seven genera) of otariids are distinguished from phocids by visible external ears (pinnae), more dog-like faces, and the ability to turn their rear flippers forward.
:Family Odobenidae currently includes a single species, the walrus. A large ({{convert|2000|kg|abbr=on|disp=or}}), distinctive pinniped with long whiskers and tusks, the walrus has a discontinuous circumpolar distribution in the Arctic Ocean and sub-Arctic seas of the Northern Hemisphere. It is primarily a benthic forager of bivalve mollusks and other marine invertebrates.
thumb|''Miacis'' is the earliest known member of the order Carnivora.
== Evolution == Caniforms first appeared as tree-climbing, superficially marten-like carnivores in the Eocene around 42 Mya. ''Miacis cognitus'' was probably an early caniform. Like many other early carnivorans it was well suited for tree climbing with needle-sharp claws, and had limbs and joints that resemble those of modern carnivorans. ''M. cognitus'' was probably a very agile forest dweller that preyed on smaller animals, such as small mammals, reptiles, and birds.
[[Image:New zealand sea lion nursing.jpg|thumb|New Zealand sea lion (''Phocarctos hookeri'')]][[File:Procyon lotor (Common raccoon).jpg|thumb|right|Common raccoon (''Procyon lotor'')]] Debate continues on the origin of pinnipeds. Recent molecular evidence suggests pinnipeds evolved from a bear-like ancestor about 23 Mya during the late Oligocene or early Miocene epochs, a transitional period between the warmer Paleogene and cooler Neogene periods.<ref name="Flynn2005"/> However, discovery of the fossil ''Puijila darwini'' in early Miocene deposits in Nunavut suggests a different scenario. Like a modern otter, ''Puijila'' had a long tail, short limbs, and webbed feet instead of flippers. However, its limbs and shoulders were more robust, and ''Puijila'' likely had been a quadrupedal swimmer–retaining a form of aquatic locomotion that give rise to the major swimming types employed by modern pinnipeds. ''Puijila'' has been assigned to a clade of mustelids.
==Classification== * Suborder: '''Caniformia''' ("dog-like" carnivorans) ** Genus: †''Lycophocyon'' ** Superfamily: '''Amphicyonoidea''' *** Family: †Amphicyonidae (bear-dogs) ** Clade: '''Canoidea''' *** Infraorder: '''Cynoidea''' **** Family: Canidae (dogs and allies) *** Infraorder: '''Arctoidea''' **** Parvorder: '''Ursida''' ***** Genus: †''Adracon'' ***** Superfamily: '''Ursoidea''' ****** Family: Ursidae (bears) **** Superfamily: '''Musteloidea''' ***** Genus: †''Plesiogale'' ***** Family: Ailuridae (red panda and allies) ***** Family: Mephitidae (skunks and stink badgers) ***** Family: Mustelidae (weasels and allies) ***** Family: Procyonidae (raccoons and allies) ***** ''Incertae sedis'': ****** Genus: †''Peignictis'' **** Clade: '''Pinnipedimorpha''' ***** Genus: †''Pinnarctidion'' ***** Family: †Enaliarctidae ***** Family: †Semantoridae ***** Clade: '''Pinnipediformes''' ****** Genus: †''Pacificotaria'' ****** Genus: †''Pteronarctos'' ****** Clade: '''Pinnipedia''' ******* Superfamily: '''Otarioidea''' ******** Family: Odobenidae (walrus and allies) ******** Family: Otariidae (eared seals) ******* Superfamily: '''Phocoidea''' ******** Family: Phocidae (true seals) ******** Family: †Desmatophocidae
=== Phylogeny === The cladogram is based on molecular phylogeny of six genes in Flynn (2005),<ref name="Flynn2005"/> with the musteloids updated following the multigene analysis of Law et al. (2018).<ref name="Law-2018">{{Cite journal|last1=Law|first1=Chris J.|last2=Slater|first2=Graham J.|last3=Mehta|first3=Rita S.|date=2018-01-01|title=Lineage Diversity and Size Disparity in Musteloidea: Testing Patterns of Adaptive Radiation Using Molecular and Fossil-Based Methods|journal=Systematic Biology|language=en|volume=67|issue=1|pages=127–144|doi=10.1093/sysbio/syx047|pmid=28472434|issn=1063-5157|doi-access=free}}</ref> {{clade | style=font-size:85%;line-height:85% |label1='''Caniformia''' |1= {{clade |1= Amphicyonidae† 50px|Ysengrinia americana |2= {{clade |1= Canidae 50px|African golden wolf |label2=Arctoidea |2= {{clade |label1=Ursoidea |1= {{clade |1= Hemicyoninae† |2= Ursidae 50px|American black bear }} |2= {{clade |label1= Pinnipedia |1= {{clade |1= Enaliarctidae† 50px |2= {{clade |1= Phocidae 50px|Common seal |2= {{clade |1= Otariidae 50px|California sea lion |2= Odobenidae 50px|Pacific walrus }} }} }} }} |3= {{clade |label1=Musteloidea |1= {{clade |1= Mephitidae 50px|Striped skunk |2= Ailuridae 50px|Red panda |3= {{clade |1= Procyonidae 50px|Common raccoon |2= Mustelidae 50px|European polecat }} }} }} }} }} }} }}
== References == {{Reflist}}
== External links ==<!-- Syst.Biol.55:301 --> * [http://taxonomicon.taxonomy.nl/TaxonTree.aspx?id=103313 Taxonomicon] * [https://web.archive.org/web/20150627120653/https://caniform.co/ Caniform] {{Carnivora|Ca.}}
{{Taxonbar|from=Q27414}} {{Authority control}}
Category:Caniformia Category:Carnivora Category:Extant Lutetian first appearances