Mammal classification
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Jc-S0CO
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/* Subclass Placentalia */ correction
[[Image:Mammal species pie chart.png|thumb|300px|right|Over 70% of mammal species are in the orders [[Rodent]]ia (blue), [[Chiroptera]] (red), and [[Soricomorpha]] (yellow)]]
[[Mammalia]] is a class of animal within the Phylum [[Chordata]]. '''Mammal classification''' has been through several iterations since [[Carolus Linnaeus]] initially defined the class. Many earlier ideas have been completely abandoned by modern taxonomists, among these are the idea that [[bat]]s are related to [[bird]]s or that [[human]]s represent a completely distinct group. Competing ideas about the relationships of mammal orders do persist and are currently in development. Most significantly in recent years, [[cladistics|cladistic]] thinking has led to an effort to ensure that all taxonomic designations represent [[monophyletic]] groups. The field has also seen a recent surge in interest and modification due to the results of [[molecular phylogeny|molecular phylogenetics]].
[[George Gaylord Simpson]]'s classic "Principles of Classification and a Classification of Mammals" ([[#References|Simpson, 1945]]) was the original source for the [[taxonomy]] listed here. Simpson laid out a [[systematics]] of [[mammal]] origins and relationships that was universally taught until the end of the 20th century.
Since Simpson's 1945 [[scientific classification|classification]], the [[fossil record|paleontological record]] has been recalibrated, and the intervening years have seen much debate and progress concerning the theoretical underpinnings of systematization itself, partly through the new concept of [[cladistics]]. Though field work gradually made Simpson's classification outdated, it remained the closest thing to an official classification of mammals.
==Molecular classification of mammals==
Molecular studies by [[molecular phylogeny|molecular systematist]]s, based on [[DNA]] analysis, have revealed new relationships among mammal families over the last few years. The most recent classification systems based on molecular studies reveal four groups or lineages of [[placental]] mammals which diverged from early common ancestors in the [[Cretaceous]].
The first divergence was that of the [[Afrotheria]] 110–100 [[million years ago]] (mya). The Afrotheria proceeded to evolve and diversify in the isolation of the African-Arabian continent. The [[Xenarthra]], isolated in [[South America]], diverged from the [[Boreoeutheria]] approximately 100–95 mya. The Boreoeutheria split into the [[Laurasiatheria]] and [[Euarchontoglires]] between 95 and 85 mya; both of these groups evolved on the northern continent of [[Laurasia]].
After tens of millions of years of relative isolation, Africa-Arabia collided with Eurasia, and the formation of the [[Isthmus of Panama]] linked [[South America]] and [[North America]], facilitating the distribution of mammals seen today. With the exception of bats and [[Murinae|murine]] rodents, no placental land mammals reached [[Australasia]] until the first human settlers arrived approximately 50,000 years ago.
It should however be noted that these molecular results are still controversial mainly because they are not reflected by [[morphology (biology)|morphological]] data and thus not accepted by many systematists. It is also important to note that fossil taxa are not and, in most cases cannot, be included. Although there are instances of DNA being recovered from prehistoric mammals such as the [[ground sloth]] ''[[Mylodon]]'' and [[Neanderthal]] humans, ''Homo neanderthalensis'', fossils can generally only be incorporated in morphological analyses.
The following taxonomy only includes living placentals (infraclass [[Eutheria]]):
===Clade [[Atlantogenata]]===
====Group I: [[Afrotheria]]====
*Clade [[Afroinsectiphilia]]
**Order [[Macroscelidea]]
***Family [[Macroscelididae]]: elephant shrews (Africa).
**Order [[Afrosoricida]]
***Family [[Tenrecidae]]: tenrecs (Madagascar) and otter-shrews (West and Central Africa).
***Family [[Chrysochloridae]]: golden moles (Africa south of the Sahara).
**Order [[Tubulidentata]]
***Family [[Orycteropodidae]]: aardvark (Africa south of the Sahara).
*Clade [[Paenungulata]]
**Order [[Proboscidea]]
***Family [[Elephantidae]]: elephants (Africa, Southeast Asia).
**Order [[Hyracoidea]]
***Family [[Procaviidae]]: hyraxes, dassies (Africa, Arabia).
**Order [[Sirenia]]
***Family [[Dugongidae]]: dugong (East Africa, Red Sea, North Australia).
***Family [[Trichechidae]]: manatees (tropical Atlantic coasts and adjacent rivers).
====Group II: [[Xenarthra]]====
*Order [[Cingulata]]
**Family [[Dasypodidae]]: armadillos (Neotropical and Nearctic)
*Order [[Pilosa]]
**Family [[Myrmecophagidae]]: anteaters (Neotropical)
**Family [[Megalonychidae]]: two-toed sloths
**Family [[Bradypodidae]]: three-toed sloths
===Clade [[Boreoeutheria]]===
====Group III [[Euarchontoglires]]====
*Superorder [[Euarchonta]]
**Order [[Scandentia]]
***Family [[Ptilocercidae]]
***Family [[Tupaiidae]]: tree shrews (Southeast Asia).
**Clade [[Primatomorpha]]
***Order [[Dermoptera]]
****Family [[Cynocephalidae]]: flying lemurs or colugos (Southeast Asia).
***Order [[Primates]]: lemurs, bushbabies, monkeys, apes ([[cosmopolitan distribution|cosmopolitan]]).
****Family [[Cheirogaleidae]]: dwarf lemurs (Madagascar)
****Family [[Lemuridae]]: lemurs (Madagascar)
****Family [[Lepilemuridae]]: mongoose lemurs (Madagascar)
****Family [[Indriidae]]: indri and sifakas (Madagascar)
****Family [[Daubentoniidae]]: aye-aye (Madagascar area)
****Family [[Lorisidae]]: lorises and potto (Africa and Southeast Asia)
****Family [[Galagidae]]: galagos (Africa)
****Family [[Tarsiidae]]: tarsiers (Southeast Asia)
****Family [[Callitrichidae]]: marmosets and tamarins (South America)
****Family [[Cebidae]]: New World monkeys (South America)
****Family [[Cercopithecidae]]: Old World monkeys (Africa and Eurasia)
****Family [[Hylobatidae]]: gibbons (Southeast Asia)
****Family [[Hominidae]]: great apes (worldwide)
*Superorder [[Glires]]
**Order [[Lagomorpha]]: pikas, rabbits, hares (Eurasia, Africa, Americas).
***Family Leporidae: rabbits and hares (Eurasia, Africa, Americas)
***Family Ochotonidae: pikas (Holarctic)
**Order [[Rodentia]]: rodents (cosmopolitan)
***Family [[Aplodontiidae]]: mountain beaver (North America)
***Family [[Sciuridae]]: squirrels, chipmunks, and marmots (cosmopolitan except Australia)
***Family [[Gliridae]]: dormice (Africa, Eurasia)
***Family [[Castoridae]]: beavers (Holarctic)
***Family [[Geomyidae]]: pocket gophers (North America)
***Family [[Heteromyidae]]: kangaroo rats (North America)
***Family [[Dipodidae]]: jerboas and jumping mice (Africa, Eurasia, North America)
***Family [[Platacanthomyidae]]: spiny dormouse (Southeast Asia)
***Family [[Spalacidae]]: zokors, root rats, blind mole rats (Africa, Eurasia)
***Family [[Calomyscidae]]: mouse-like hamsters (Asia)
***Family [[Nesomyidae]]: old endemic African muroids (Africa, Madagascar)
***Family [[Cricetidae]]: hamsters, voles, and New World rats and mice (Holarctic, South America)
***Family [[Muridae]]: Old World rats and mice and gerbils (Africa, Eurasia, Australia)
***Family [[Anomaluridae]]: scaly-tailed flying squirrels (Africa)
***Family [[Pedetidae]]: springhaas (Africa)
***Family [[Ctenodactylidae]]: gundis (Africa, Asia)
***Family [[Hystricidae]]: Old World porcupines (Africa, Asia)
***Family [[Bathyergidae]]: African mole-rats (Africa)
***Family [[Petromuridae]]: rock dassies (Africa)
***Family [[Thryonomyidae]]: cane rats (Africa)
***Family [[Erethizontidae]]: New World porcupines (New World)
***Family [[Chinchillidae]]: chinchillas and viscachas (South America)
***Family [[Dinomyidae]]: pacarana (South America)
***Family [[Caviidae]]: cavies and capybara (South America)
***Family [[Dasyproctidae]]: agoutis and acouchis (South America)
***Family [[Agoutidae]]: paca (South America)
***Family [[Ctenomyidae]]: tuco-tucos (South America)
***Family [[Octodontidae]]: degus (South America)
***Family [[Abrocomidae]]: chinchilla-rats (South America)
***Family [[Echimyidae]]: spiny rats (South America)
***Family [[Capromyidae]]: hutias (South America)
***Family [[Myocastoridae]]: nutrias (South America)
====Group IV: [[Laurasiatheria]]====
*Order [[Soricomorpha]]
**Family [[Solenodontidae]]: solenodons (Cuba, Hispaniola).
**Family [[Soricidae]]: shrews (Eurasia, Africa, North America to northern South America).
**Family [[Talpidae]]: moles, shrew-moles, desmans (Eurasia, North America).
*Order [[Erinaceomorpha]]
**Family [[Erinaceidae]]: hedgehogs, moonrats (Eurasia, Africa).
*Clade [[Ferungulata]]
**Order [[Cetartiodactyla]]: includes former orders [[Artiodactyla]] and [[Cetacea]]
***Family [[Camelidae]]: camels (South America, Asia)
***Family [[Suidae]]: pigs (Africa, Eurasia)
***Family [[Tayassuidae]]: peccaries (New World)
***Family [[Hippopotamidae]]: hippos (Africa)
***Family [[Balaenopteridae]]: rorquals and grey whales
***Family [[Balaenidae]]: right and bowhead whales
***Family [[Physeteridae]]: sperm whales
***Family [[Hyperoodontidae]]: beaked whales
***Family [[Platanistidae]]: river dolphins
***Family [[Delphinidae]]: dolphins
***Family [[Pontoporiidae]]: La Plata River dolphin
***Family [[Lipotidae]]: baiji
***Family [[Iniidae]]: Amazon River dolphin
***Family [[Monodontidae]]: beluga and narwhal
***Family [[Phocoenidae]]: porpoises
***Family [[Tragulidae]]: mouse-deer (Africa, Asia)
***Family [[Antilocapridae]]: pronghorn (North America)
***Family [[Giraffidae]]: giraffe and okapi (Africa)
***Family [[Cervidae]]: deer (Holarctic, South America)
***Family [[Moschidae]]: musk deer (Asia)
***Family [[Bovidae]]: cattle, antelope, sheep, etc. (Africa, Holarctic)
**Clade [[Pegasoferae]]
***Order [[Chiroptera]]: bats (cosmopolitan)
****Family [[Pteropodidae]]: flying foxes (Africa, Eurasia, Australia)
****Family [[Rhinolophidae]]: Old World horseshoe and leaf-nosed bats (Old World)
****Family [[Emballonuridae]]: sac-winged bats (southern continents)
****Family [[Craseonycteridae]]: Kitti's hog-nosed bat (Thailand)
****Family [[Rhinopomatidae]]: mouse-tailed bats (Africa, Southeast Asia)
****Family [[Nycteridae]]: slit-faced bats (Africa, Southeast Asia)
****Family [[Megadermatidae]]: false vampire bats (Africa, Southeast Asia, Australia)
****Family [[Phyllostomidae]]: leaf-nosed bats (South America)
****Family [[Mormoopidae]]: leaf-chinned bats (South America)
****Family [[Noctilionidae]]: fishing bats (South America)
****Family [[Mystacinidae]]: short-tailed bats (New Zealand)
****Family [[Molossidae]]: free-tailed bats (cosmopolitan)
****Family [[Myzopodidae]]: sucker-footed bats (Madagascar)
****Family [[Thyropteridae]]: sucker-footed bats (South America)
****Family [[Furipteridae]]: smoky bats (South America)
****Family [[Natalidae]]: funnel-eared bats (South America)
****Family [[Vespertilionidae]]: vesper bats (cosmopolitan)
***Order [[Perissodactyla]]: odd-toed ungulates
****Family [[Equidae]]: horses, zebras, donkeys (Africa, West and Central Asia).
****Family [[Tapiridae]]: tapirs (Central and South America, Southeast Asia).
****Family [[Rhinocerotidae]]: rhinoceroses (Africa, Southeast Asia).
***Clade [[Ferae]]
****Order [[Pholidota]]
*****Family [[Manidae]]: pangolins, scaly anteaters (Africa, South Asia).
****Order [[Carnivora]]: carnivorans (cosmopolitan)
*****Family [[Felidae]]: cats
*****Family [[Viverridae]]: civets, Asiatic palm civets
*****Family [[Herpestidae]]: mongooses
*****Family [[Hyaenidae]]: hyaenas, aardwolf
*****Family [[Canidae]]: dogs
*****Family [[Ursidae]]: bears
*****Family [[Otariidae]]: eared seals
*****Family [[Odobenidae]]: walrus
*****Family [[Phocidae]]: seals, walrus
*****Family [[Ailuridae]]: red panda
*****Family [[Mephitidae]]: skunks
*****Family [[Mustelidae]]: weasels and relatives
*****Family [[Procyonidae]]: ringtails, olingos, kinkajou, raccoons, coatis, red panda
==Standardized textbook classification==
A somewhat standardized classification system has been adopted by most current [[mammalogy]] classroom textbooks. The following taxonomy of extant and recently extinct mammals is taken from [[#References|Vaughan et al. (2000)]]. This approach emphasizes an initial split between egg-laying prototherians and live-bearing therians. The therians are further divided into the marsupial Metatheria and the "placental" Eutheria. No attempt is made here to further distinguish among the orders within these subclasses and infraclasses. This system also makes no note of the position of entirely fossil groups.
In this and later taxonomies listed here, families are merely listed under the order to which they belong. Please see the pages associated with specific orders to see more detailed relationships among families in that order.
===Subclass [[Prototheria]]===
*Order [[Monotremata]]
**Family [[Tachyglossidae]] (echidnas)
**Family [[Ornithorhynchidae]] (platypuses)
===Subclass [[Theria]]===
*Infraclass [[Metatheria]] (marsupials and their nearest ancestors)
**Order [[Didelphimorphia]]
***Family [[Didelphidae]] (opossums, etc.)
**Order [[Paucituberculata]]
***Family [[Caenolestidae]] (shrew opossums)
**Order [[Microbiotheria]]
***Family [[Microbiotheriidae]] (monito del montes)
**Order [[Dasyuromorphia]] (most carnivorous marsupials)
***Family [[Thylacinidae]] (Tasmanian tigers)
***Family [[Myrmecobiidae]] (numbats)
***Family [[Dasyuridae]] (Tasmanian devils, quolls, dunnarts, planigale, etc.)
**Order [[Peramelemorphia]] (bandicoots, bilbies, etc.)
***Family [[Peramelidae]]
***Family [[Peroryctidae]]
**Order [[Notoryctemorphia]] (marsupial moles)
***Family [[Notoryctidae]]
**Order [[Diprotodontia]]
***Family [[Phascolarctidae]] (koalas)
***Family [[Vombatidae]] (wombats)
***Family [[Phalangeridae]] (brushtail possums and cuscuses)
***Family [[Potoroidae]] (bettongs, potaroos and rat kangaroos)
***Family [[Macropodidae]] (kangaroos, wallabies, etc.)
***Family [[Burramyidae]] (pygmy possums)
***Family [[Pseudocheiridae]] (ringtailed possums, etc.)
***Family [[Petauridae]] ([[Striped Possum]], [[Leadbeater's Possum]], [[Yellow-bellied Glider]], [[Sugar Glider]], [[Mahogany Glider]] and [[Squirrel Glider]])
***Family [[Tarsipedidae]] (honey possum)
***Family [[Acrobatidae]] ([[Feathertail Glider]] and [[Feather-tailed Possum]])
*Infraclass [[Eutheria]]
**Order [[Xenarthra]]
***Family [[Bradypodidae]]
***Family [[Megalonychidae]]
***Family [[Dasypodidae]]
***Family [[Myrmecophagidae]]
**Order [[Insectivora]]
***Family [[Solenodontidae]]
***Family [[Nesophontidae]]
***Family [[Tenrecidae]]
***Family [[Chrysochloridae]]
***Family [[Erinaceidae]]
***Family [[Soricidae]]
***Family [[Talpidae]]
**Order [[Scandentia]]
***Family [[Tupaiidae]]
**Order [[Dermoptera]]
***Family [[Cynocephalidae]]
**Order [[Chiroptera]]
***Family [[Pteropodidae]]
***Family [[Emballonuridae]]
***Family [[Craseonycteridae]]
***Family [[Rhinopomatidae]]
***Family [[Nycteridae]]
***Family [[Megadermatidae]]
***Family [[Rhinolophidae]]
***Family [[Phyllostomidae]]
***Family [[Mormoopidae]]
***Family [[Noctilionidae]]
***Family [[Mystacinidae]]
***Family [[Molossidae]]
***Family [[Myzopodidae]]
***Family [[Thyropteridae]]
***Family [[Furipteridae]]
***Family [[Natalidae]]
***Family [[Vespertilionidae]]
**Order [[Primates]]
***Family [[Daubentoniidae]]
***Family [[Lemuridae]]
***Family [[Lepilemuridae]]
***Family [[Galagidae]]
***Family [[Lorisidae]]
***Family [[Cheirogaleidae]]
***Family [[Indriidae]]
***Family [[Tarsiidae]]
***Family [[Cercopithecidae]]
***Family [[Hominidae]]
***Family [[Hylobatidae]]
***Family [[Callitrichidae]]
***Family [[Cebidae]]
**Order [[Carnivora]]
***Family [[Felidae]]
***Family [[Viverridae]]
***Family [[Herpestidae]]
***Family [[Hyaenidae]]
***Family [[Canidae]]
***Family [[Ursidae]]
***Family [[Otariidae]]
***Family [[Phocidae]]
***Family [[Odobenidae]]
***Family [[Mustelidae]]
***Family [[Procyonidae]]
**Order [[Cetacea]]
***Family [[Balaenopteridae]]
***Family [[Eschrichtiidae]]
***Family [[Balaenidae]]
***Family [[Neobalaenidae]]
***Family [[Physeteridae]]
***Family [[Ziphiidae]]
***Family [[Platanistidae]]
***Family [[Delphinidae]]
***Family [[Monodontidae]]
***Family [[Phocoenidae]]
**Order [[Sirenia]]
***Family [[Dugongidae]]
***Family [[Trichechidae]]
**Order [[Proboscidea]]
***Family [[Elephantidae]]
**Order [[Perissodactyla]]
***Family [[Equidae]]
***Family [[Tapiridae]]
***Family [[Rhinocerotidae]]
**Order [[Hyracoidea]]
***Family [[Procaviidae]]
**Order [[Tubulidentata]]
***Family [[Orycteropodidae]]
**Order [[Artiodactyla]]
***Family [[Suidae]]
***Family [[Tayassuidae]]
***Family [[Hippopotamidae]]
***Family [[Camelidae]]
***Family [[Tragulidae]]
***Family [[Giraffidae]]
***Family [[Moschidae]]
***Family [[Cervidae]]
***Family [[Antilocapridae]]
***Family [[Bovidae]]
**Order [[Pholidota]]
***Family [[Manidae]]
**Order [[Rodentia]]
***Family [[Aplodontiidae]]
***Family [[Sciuridae]]
***Family [[Castoridae]]
***Family [[Geomyidae]]
***Family [[Heteromyidae]]
***Family [[Dipodidae]]
***Family [[Muroidea|Muridae]]
***Family [[Anomaluridae]]
***Family [[Pedetidae]]
***Family [[Ctenodactylidae]]
***Family [[Myoxidae]]
***Family [[Bathyergidae]]
***Family [[Hystricidae]]
***Family [[Petromuridae]]
***Family [[Thryonomyidae]]
***Family [[Erethizontidae]]
***Family [[Chinchillidae]]
***Family [[Dinomyidae]]
***Family [[Caviidae]]
***Family [[Hydrochaeridae]]
***Family [[Dasyproctidae]]
***Family [[Agoutidae]]
***Family [[Ctenomyidae]]
***Family [[Octodontidae]]
***Family [[Abrocomidae]]
***Family [[Echimyidae]]
***Family [[Capromyidae]]
***Family [[Heptaxodontidae]]
***Family [[Myocastoridae]]
**Order [[Lagomorpha]]
***Family [[Ochotonidae]]
***Family [[Leporidae]]
**Order [[Macroscelidea]]
***Family [[Macroscelididae]]
==McKenna/Bell classification==
In 1997, the mammals were comprehensively revised by Malcolm C. McKenna and Susan K. Bell, which has resulted in the "McKenna/Bell classification".
McKenna and Bell, ''Classification of Mammals: Above the species level,'' ([[#References|McKenna & Bell, 1997)]] is the most comprehensive work to date on the systematics, relationships, and occurrences of all mammal taxa, living and extinct, down through the rank of genus. The new McKenna/Bell classification was quickly accepted by paleontologists. The authors work together as [[paleontologists]] at the [[American Museum of Natural History]], New York. McKenna inherited the project from Simpson and, with Bell, constructed a completely updated hierarchical system, covering living and extinct taxa that reflects the historical genealogy of Mammalia.
The McKenna/Bell hierarchical listing of all of the terms used for mammal groups above the species includes extinct mammals as well as modern groups, and introduces some fine distinctions such as [[legion (biology)|legions]] and [[sublegions]] (ranks which fall between classes and orders) that are likely to be glossed over by the layman.
The published re-classification forms both a comprehensive and authoritative record of approved names and classifications and a list of invalid names.
Click on the highlighted link for a [http://www.utep.edu/leb/classification/table1a.htm table comparing the traditional and the new McKenna/Bell classifications of mammals]
[[Extinct]] groups are represented by †.
===Subclass [[Prototheria]]===
(monotremes)
*Order [[Platypoda]]: platypuses
**Family [[Ornithorhynchidae]]: platypuses
*Order [[Tachyglossa]]: echidnas (spiny anteaters)
**Family [[Tachyglossidae]]: echidnas
===Subclass [[Theriiformes]]===
*Infraclass †[[Allotheria]]
**Order †[[Multituberculata]]: multituberculates
***Family †[[Plagiaulacidae]]
***Family †[[Bolodontidae]]
***Family †[[Hahnodontidae]]
***Family †[[Albionbaataridae]]
***Family †[[Arginbaataridae]]
***Family †[[Kogaionidae]]
***Family †[[Sloanbaataridae]]
***Family †[[Cimolodontidae]]
***Family †[[Ptilodontidae]]
***Family †[[Cimolomyidae]]
***Family †[[Eucosmodontidae]]
***Family †[[Taeniolabididae]]
***Family †[[Ferugliotheriidae]]
***Family †[[Sudamericidae]]
*Infraclass †[[Triconodonta]]
**Family †[[Austrotriconodontidae]]
**Family †[[Amphilestidae]]
**Family †[[Triconodontidae]]
*Infraclass [[Holotheria]]
**Family †[[Chronoperatidae]]
**Superlegion †[[Kuehneotheria]]
***Family †[[Kuehneotheriidae]]
***Family †[[Woutersiidae]]
**Superlegion [[Trechnotheria]]
***Legion †[[Symmetrodonta]]
****Family †[[Shuotheriidae]]
****Order †[[Amphidontoidea]]
*****Family †[[Amphidontidae]]
****Order †[[Spalacotherioidea]]
*****Family †[[Tinodontidae]]
*****Family †[[Spalacotheriidae]]
*****Family †[[Barbereniidae]]
***Legion [[Cladotheria]]
****Sublegion †[[Dryolestoidea]]
*****Order †[[Dryolestida]]
******Family †[[Dryolestidae]]
******Family †[[Paurodontidae]]
******Family †[[Donodontidae]]
******Family †[[Mesungulatidae]]
******Family †[[Reigitheriidae]]
******Family †[[Brandoniidae]]
*****Order †[[Amphitheriida]]
******Family †[[Amphitheriidae]]
****Sublegion [[Zatheria]]
*****Family †[[Arguitheriidae]]
*****Family †[[Arguimuridae]]
*****Family †[[Vincelestidae]]
*****Infralegion †[[Peramura]]
******Family †[[Peramuridae]]
*****Infralegion [[Tribosphenida]]
******Family †[[Necrolestidae]]
******Supercohort †[[Aegialodontia]]
*******Family †[[Aegialodontidae]]
******Supercohort [[Theria]]: therian mammals
*******Family †[[Pappotheriidae]]
*******Family †[[Holoclemensiidae]]
*******Family †[[Kermackiidae]]
*******Family †[[Endotheriidae]]
*******Family †[[Picopsidae]]
*******Family †[[Potamotelsidae]]
*******Family †[[Plicatodontidae]]
*******Order †[[Deltatheroida]]
********Family †[[Deltatheridiidae]]
********Family †[[Deltatheroididae]]
*******Order †[[Asiadelphia]]
********Family †[[Asiatheriidae]]
*******Cohort [[Marsupialia]]: marsupials
********Family †[[Yingabalanaridae]]
********Family †[[Stagodontidae]]
********Family †[[Pediomyidae]]
********Magnorder [[Australidelphia]]
*********Superorder [[Microbiotheria]]
**********Family [[Microbiotheriidae]]: monito del monte
*********Superorder [[Eometatheria]]
**********Order †[[Yalkaparidontia]]
***********Family †[[Yalkaparidontidae]]
**********Order [[Notoryctemorphia]]: marsupial moles
***********Family [[Notoryctidae]]: marsupial moles
**********Grandorder [[Dasyuromorphia]]: marsupial carnivores
***********Family †[[Thylacinidae]]: recently extinct Tasmanian tiger and relatives
***********Family [[Dasyuridae]]: Tasmanian devil, quolls, etc.
***********Family [[Myrmecobiidae]]: numbat
**********Grandorder [[Syndactyli]]: syndactylous marsupials
***********Order [[Peramelia]]: bandicoots
************Family [[Peramelidae]]
************Family [[Peroryctidae]]
***********Order [[Diprotodontia]]
************Family †[[Palorchestidae]]
************Family †[[Wynardiidae]]
************Family †[[Thylacoleonidae]]
************Family [[Tarsipedidae]]: honey possum
************Family †[[Ilariidae]]
************Family †[[Diprotodontidae]]
************Family [[Vombatidae]]: wombats
************Family [[Phalangeridae]]: phalangers
************Family [[Burramyidae]]: pygmy possums
************Family [[Macropodidae]]: rat kangaroos, kangaroos and wallabies
************Family [[Petauridae]]: gliders
************Family †[[Ektopodontidae]]
************Family [[Phascolarctidae]]: koala
************Family †[[Pilkipildridae]]
************Family †[[Miralinidae]]
************Family [[Acrobatidae]]: feather-tail glider, pen-tailed phalanger
********Magnorder [[Ameridelphia]]
*********Order [[Didelphimorphia]]: opossums
**********Family [[Didelphidae]]: opossums
**********Family †[[Sparassocynidae]]
*********Order [[Paucituberculata]]
**********Family †[[Sternbergiidae]]
**********Family [[Caenolestidae]]: rat or shrew opossums
**********Family †[[Paleothentidae]]
**********Family †[[Abderitidae]]
**********Family †[[Sillustaniidae]]
**********Family †[[Polydolopidae]]
**********Family †[[Prepidolopidae]]
**********Family †[[Bonapartheriidae]]
**********Family †[[Argyrolagidae]]
**********Family †[[Patagoniidae]]
**********Family †[[Groeberiidae]]
**********Family †[[Glasbiidae]]
**********Family †[[Caroloameghiniidae]]
*********Order †[[Sparassodonta]]
**********Family †[[Mayulestidae]]
**********Family †[[Hondadelphidae]]
**********Family †[[Borhyaenidae]]
*******Cohort [[Placentalia]]: placentals
********Order †[[Bibymalagasia]]
********Magnorder [[Xenarthra]]: edentates
*********Order [[Cingulata]]: armadillos and relatives
**********Family [[Dasypodidae]]: armadillos
**********Family †[[Peltephilidae]]
**********Family †[[Pampatheriidae]]
**********Family †[[Palaeopeltidae]]
**********Family †[[Glyptodontidae]]: glyptodonts
*********Order [[Pilosa]]: anteaters, sloths, and relatives
**********Family †[[Entelopidae]]
**********Family [[Myrmecophagidae]]: giant anteaters and relatives
**********Family [[Cyclopedidae]]: pygmy anteater
**********Family †[[Rathymotheriidae]]
**********Family †[[Scelidotheriidae]]
**********Family †[[Mylodontidae]]
**********Family †[[Megatheriidae]]: ground sloths
**********Family [[Megalonychidae]]: two-toed sloths
**********Family [[Bradypodidae]]: three-toed sloths
********Magnorder [[Epitheria]]: epitheres
*********Superorder †[[Leptictida]]
**********Family †[[Gypsonictopidae]]
**********Family †[[Kulbeckiidae]]
**********Family †[[Didymoconidae]]
**********Family †[[Leptictidae]]
*********Superorder [[Preptotheria]]
**********Grandorder [[Anagalida]]
***********Family †[[Zambdalestidae]]
***********Family †[[Anagalidae]]
***********Family †[[Pseudictopidae]]
***********Mirorder [[Macroscelidea]]: elephant shrews
************Family [[Macroscelididae]]: elephant shrews
***********Mirorder [[Duplicidentata]]
************Order †[[Mimotonida]]
*************Family †[[Mimotonidae]]
************Order [[Lagomorpha]]
*************Family [[Ochotonidae]]: pikas
*************Family [[Leporidae]]: rabbits
***********Mirorder [[Simplicidentata]]
************Order †[[Mixodontia]]
*************Family †[[Eurymylidae]]
************Order [[Rodentia]]: rodents
*************Family †[[Alagomyidae]]
*************Family †[[Laredomyidae]]
*************Family †[[Ischyromyidae]]
*************Family †[[Allomyidae]]
*************Family [[Aplodontiidae]]: mountain beaver
*************Family †[[Mylagaulidae]]
*************Family †[[Theridomyidae]]
*************Family †[[Reithroparamyidae]]
*************Family [[Sciuridae]]: squirrels
*************Family †[[Eutypomyidae]]
*************Family [[Castoridae]]: beavers
*************Family †[[Rhizospalacidae]]
*************Family †[[Protoptychidae]]
*************Family †[[Armintomyidae]]
*************Family [[Dipodidae]]: jumping mice, jerboas
*************Family †[[Simimyidae]]
*************Family [[Muroidea|Muridae]]: rats, mice, and relatives
*************Family [[Myoxidae]]: dormice
*************Family †[[Eomyidae]]
*************Family †[[Florentiamyidae]]
*************Family [[Geomyidae]]: pocket gophers, pocket mice, and kangaroo rats
*************Family [[Pedetidae]]: springhaas
*************Family †[[Parapedetidae]]
*************Family †[[Zegdoumyidae]]
*************Family [[Anomaluridae]]: scaly-tailed squirrels
*************Family †[[Ivanantoniidae]]
*************Family †[[Sciuravidae]]
*************Family †[[Chapattimyidae]]
*************Family †[[Cylindrodontidae]]
*************Family [[Ctenodactylidae]]: gundis
*************Family †[[Tsaganomyidae]]
*************Family [[Hystricidae]]: Old World porcupines
*************Family [[Erethizontidae]]: New World porcupines
*************Family †[[Myophiomyidae]]
*************Family †[[Diamantomyidae]]
*************Family †[[Phiomyidae]]
*************Family †[[Kenyamyidae]]
*************Family [[Petromuridae]]: rock rats
*************Family [[Thryonomyidae]]: cane rats
*************Family [[Bathyergidae]]: mole-rats
*************Family †[[Bathyergoididae]]
*************Family [[Agoutidae]]: agoutis and pacas
*************Family †[[Eocardiidae]]
*************Family [[Dinomyidae]]: pacarana
*************Family [[Caviidae]]: cavies
*************Family [[Hydrochoeridae]]: capybara
*************Family [[Octodontidae]]: degus, tuco-tucos
*************Family [[Echimyidae]]: spiny rats, nutria
*************Family [[Capromyidae]]: hutias
*************Family †[[Heptaxodontidae]]
*************Family [[Chinchillidae]]: chinchillas, viscachas
*************Family †[[Neoepiblemidae]]
*************Family [[Abrocomidae]]: rat chinchillas
**********Grandorder [[Ferae]]
***********Order [[Cimolesta]] - pangolins and relatives
************Family †[[Palaeoryctidae]]
************Family †[[Cimolestidae]]
************Family †[[Apatemyidae]]
************Family †[[Taeniodont|Stylinodontidae]]
************Family †[[Tillotheriidae]]
************Family †[[Wangliidae]]
************Family †[[Harpyodidae]]
************Family †[[Bemalambdidae]]
************Family †[[Pastoralodontidae]]
************Family †[[Titanoideidae]]
************Family †[[Pantolambdidae]]
************Family †[[Barylambdidae]]
************Family †[[Cyriacotheriidae]]
************Family †[[Pantolambdodontidae]]
************Family †[[Coryphodontidae]]
************Family †[[Pantolestidae]]
************Family †[[Paroxyclaenidae]]
************Family †[[Ptolemaiidae]]
************Family †[[Epoicotheriidae]]
************Family †[[Metacheiromyidae]]
************Family [[Manidae]]: pangolins
************Family †[[Ernanodontidae]]
***********Order †[[Creodonta]]: creodonts
************Family †[[Hyaenodontidae]]
************Family †[[Oxyaenidae]]
***********Order [[Carnivora]]
************Family †[[Viverravidae]]
************Family †[[Nimravidae]]
************Family [[Felidae]]: cats
************Family [[Viverridae]]: civets, Asiatic palm civets
************Family [[Herpestidae]]: mongooses
************Family [[Hyaenidae]]: hyaenas, aardwolf
************Family [[Nandiniidae]]: African palm civets
************Family †[[Miacidae]]
************Family [[Canidae]]: dogs
************Family †[[Amphicyonidae]]
************Family [[Ursidae]]: bears
************Family †[[Hemicyonidae]]
************Family [[Otariidae]]: eared seals
************Family [[Phocidae]]: seals, walrus
************Family [[Mustelidae]]: weasels, skunks, and relatives
************Family [[Procyonidae]]: ringtails, olingos, kinkajou, raccoons, coatis, red panda
**********Grandorder [[Lipotyphla]]
***********Family †[[Adapisoriculidae]]
************Order [[Chrysochloridea]]
*************Family [[Chrysochloridae]]: golden moles
************Order [[Erinaceomorpha]]
*************Family †[[Sespedectidae]]
*************Family †[[Amphilemuridae]]
*************Family †[[Adapisoricidae]]
*************Family †[[Creotarsidae]]
*************Family [[Erinaceidae]]: hedgehogs and relatives
*************Family †[[Proscalopidae]]
*************Family [[Talpidae]]: moles
*************Family †[[Dimylidae]]
************Order [[Soricomorpha]]
*************Family †[[Otlestidae]]
*************Family †[[Geolabididae]]
*************Family †[[Nesophontidae]]: recently extinct west Indian shrews
*************Family †[[Micropternodontidae]]
*************Family †[[Apternodontidae]]
*************Family [[Solenodontidae]]: solenodons
*************Family †[[Plesiosoricidae]]
*************Family †[[Nyctitheriidae]]
*************Family [[Soricidae]]: shrews
*************Family [[Tenrecidae]]: tenrecs
**********Grandorder [[Archonta]]
***********Order [[Chiroptera]]: bats
************Family [[Pteropodidae]]: flying foxes
************Family †[[Archaeonycteridae]]
************Family †[[Paleochiropterygidae]]
************Family †[[Hassianycterididae]]
************Family [[Emballonuridae]]: sac-winged bats
************Family [[Rhinopomatidae]]: mouse-tailed bats
************Family [[Craseonycteridae]]: bumblebee bats
************Family [[Megadermatidae]]: false vampire bats
************Family [[Nycteridae]]: hispid bats
************Family [[Rhinolophidae]]: horseshoe and Old World leaf-nosed bats
************Family [[Mystacinidae]]: New Zealand short-tailed bats
************Family [[Noctilionidae]]: fishing bats
************Family [[Mormoopidae]]: spectacled bats
************Family [[Phyllostomidae]]: New World leaf-nosed and vampire bats
************Family †[[Philisidae]]
************Family [[Molossidae]]: free-tailed bats
************Family [[Natalidae]]: funnel-eared bats
************Family [[Furipteridae]]: smoky bats
************Family [[Thyropteridae]]: New World sucker-footed bats
************Family [[Myzopodidae]]: Old World sucker-footed bats
************Family [[Vespertilionidae]]: common bats
***********Order [[Primates]]: primates
************Family †[[Purgatoriidae]]
************Family †[[Microsyopidae]]
************Family †[[Micromomyidae]]
************Family †[[Picromomyidae]]
************Family †[[Plesiadapidae]]
************Family †[[Palaechthonidae]]
************Family †[[Picrodontidae]]
************Family †[[Paramomyidae]]
************Family †[[Plagiomenidae]]
************Family †[[Mixodectidae]]
************Family [[Galeopithecidae]]: colugos
************Family †[[Plesiopithecidae]]
************Family [[Daubentoniidae]]: aye-aye
************Family †[[Adapidae]]
************Family [[Lemuridae]]: lemurs
************Family [[Lorisidae]]: lorises and galagos
************Family [[Cheirogaleidae]]: dwarf lemurs
************Family †[[Archaeolemuridae]]
************Family †[[Palaeopropithecidae]]
************Family [[Indriidae]]: indris and sifakas
************Family †[[Carpolestidae]]
************Family †[[Omomyidae]]
************Family †[[Microchoeridae]]
************Family †[[Afrotarsiidae]]
************Family [[Tarsiidae]]: tarsiers
************Family †[[Eosimiidae]]
************Family †[[Parapithecidae]]
************Family †[[Pliopithecidae]]
************Family [[Cercopithecidae]]: Old World monkeys including colobuses
************Family [[Hominidae]]: humans, greater apes, lesser apes
************Family [[Callitrichidae]]: marmosets
************Family [[Atelidae]]: New World monkeys
***********Order [[Scandentia]]
************Family [[Tupaiidae]]: tree shrews
**********Grandorder [[Ungulata]]: ungulates
***********Order [[Tubulidentata]]
************Family [[Orycteropodidae]]: aardvark
***********Order †[[Dinocerata]]
************Family †[[Uintatheriidae]]
***********Mirorder [[Eparctocyona]]
************Order †[[Procreodi]]
*************Family †[[Oxyclaenidae]]
*************Family †[[Arctocyonidae]]
************Order †[[Condylarthra]]
*************Family †[[Hyopsodontidae]]
*************Family †[[Mioclaenidae]]
*************Family †[[Phenacodontidae]]
*************Family †[[Periptychidae]]
*************Family †[[Peligrotheriidae]]
*************Family †[[Didolodontidae]]
************Order †[[Arctostylopida]]
*************Family †[[Arctostylopidae]]
************Order [[Cete]]: whales and relatives
*************Family †[[Triisodontidae]]
*************Family †[[Mesonychidae]]: mesonychids
*************Family †[[Hapalodectidae]]
*************Family †[[Basilosauridae]]
*************Family †[[Protocetidae]]
*************Family †[[Remingtonocetidae]]
*************Family †[[Agorophiidae]]
*************Family †[[Squalodontidae]]
*************Family †[[Rhabdosteidae]]
*************Family †[[Aetiocetidae]]
*************Family †[[Mammalodontidae]]
*************Family †[[Cetotheriidae]]
*************Family [[Balaenopteridae]]: rorquals and grey whales
*************Family [[Balaenidae]]: right and bowhead whales
*************Family [[Physeteridae]]: sperm whales
*************Family [[Hyperoodontidae]]: beaked whales
*************Family [[Platanistidae]]: river dolphins
*************Family [[Delphinidae]]: dolphins
*************Family [[Pontoporiidae]]: La Plata River dolphin
*************Family [[Lipotidae]]: baiiji
*************Family [[Iniidae]]: Amazon River dolphin
*************Family †[[Kentridontidae]]
*************Family [[Monodontidae]]: beluga and narwhal
*************Family †[[Odobenocetopsidae]]
*************Family †[[Dalpiazinidae]]
*************Family †[[Acrodelphinidae]]
*************Family [[Phocoenidae]]: porpoises
*************Family †[[Albireonidae]]
*************Family †[[Hemisyntrachelidae]]
************Order [[Artiodactyla]]: even-toed ungulates
*************Family †[[Raoellidae]]
*************Family †[[Choeropotamidae]]
*************Family [[Suidae]]: pigs
*************Family [[Tayassuidae]]: peccaries
*************Family †[[Santheriidae]]
*************Family [[Hippopotamidae]]: hippos
*************Family †[[Dichobunidae]]
*************Family †[[Cebochoeridae]]
*************Family †[[Mixtotheriidae]]
*************Family †[[Helohyidae]]
*************Family †[[Haplobunodontidae]]
*************Family †[[Anthracotheriidae]]
*************Family †[[Dacrytheriidae]]
*************Family †[[Anoplotheriidae]]
*************Family †[[Cainotheriidae]]
*************Family †[[Agriochoeridae]]
*************Family †[[Oreodont]]idae
*************Family †[[Entelodontidae]]
*************Family †[[Xiphodontidae]]
*************Family [[Camelidae]]: camels and llamas
*************Family †[[Oromerycidae]]
*************Family †[[Protoceratidae]]
*************Family †[[Amphimerycidae]]
*************Family †[[Hypertragulidae]]
*************Family [[Tragulidae]]: mouse deer
*************Family †[[Leptomerycidae]]
*************Family †[[Bachitheriidae]]
*************Family †[[Lophiomerycidae]]
*************Family †[[Gelocidae]]
*************Family [[Moschidae]]: musk deer
*************Family [[Antilocapridae]]: pronghorn
*************Family †[[Palaeomerycidae]]
*************Family †[[Hoplitomerycidae]]
*************Family [[Cervidae]]: deer
*************Family †[[Climacoceratidae]]
*************Family [[Giraffidae]]: giraffe and okapi
*************Family [[Bovidae]]: cattle, antelope, and relatives
***********Mirorder †[[Meridiungulata]]
************Family †[[Perutheriidae]]
************Family †[[Amilnedwardsiidae]]
************Order †[[Litopterna]]
*************Family †[[Protolipternidae]]
*************Family †[[Macraucheniidae]]
*************Family †[[Notonychopidae]]
*************Family †[[Adianthidae]]
*************Family †[[Proterotheriidae]]
************Order †[[Notoungulata]]: notoungulates
*************Family †[[Henricosborniidae]]
*************Family †[[Notostylopidae]]
*************Family †[[Isotemnidae]]
*************Family †[[Leontiniidae]]
*************Family †[[Notohippidae]]
*************Family †[[Toxodontidae]]
*************Family †[[Homalodotheriidae]]
*************Family †[[Archaeopithecidae]]
*************Family †[[Oldfieldthomasiidae]]
*************Family †[[Interatheriidae]]
*************Family †[[Campanorcidae]]
*************Family †[[Mesotheriidae]]
*************Family †[[Archaeohyracidae]]
*************Family †[[Hegetotheriidae]]
************Order †[[Astrapotheria]]
*************Family †[[Eoastrapostylopidae]]
*************Family †[[Trigonostylopidae]]
*************Family †[[Astrapotheriidae]]
************Order †[[Xenungulata]]
*************Family †[[Carodniidae]]
************Order †[[Pyrotheria]]
*************Family †[[Pyrotheriidae]]
***********Mirorder [[Altungulata]]
************Order [[Perissodactyla]]: odd-toed ungulates
*************Family [[Equidae]]: horses
*************Family †[[Palaeotheriidae]]
*************Family †[[Brontotheriidae]]
*************Family †[[Anchilophidae]]
*************Family †[[Eomoropidae]]
*************Family †[[Chalicotheriidae]]
*************Family †[[Hyracodontidae]]
*************Family [[Rhinocerotidae]]: rhinoceroses
*************Family †[[Helaletidae]]
*************Family †[[Isectolophidae]]
*************Family †[[Lophiodontidae]]
*************Family †[[Deperetellidae]]
*************Family †[[Lophialetidae]]
*************Family [[Tapiridae]]: tapirs
************Order [[Uranotheria]]: elephants, manatees, hyraxes, and relatives
*************Family †[[Pliohyracidae]]
*************Family [[Procaviidae]]: hyraxes
*************Family †[[Phenacolophidae]]
*************Family †[[Arsinoitheriidae]]
*************Family †[[Prorastomidae]]
*************Family [[Dugongidae]]: dugongs
*************Family [[Trichechidae]]: manatees
*************Family †[[Desmostylidae]]
*************Family †[[Anthracobunidae]]
*************Family †[[Moeritheriidae]]
*************Family †[[Numidotheriidae]]
*************Family †[[Barytheriidae]]
*************Family †[[Deinotheriidae]]
*************Family †[[Palaeomastodontidae]]
*************Family †[[Phiomiidae]]
*************Family †[[Hemimastodontidae]]
*************Family †[[Mammutidae]]: mastodons and relatives
*************Family †[[Gomphotheriidae]]: gomphotheres
*************Family [[Elephantidae]]: modern elephants
==Luo, Kielan-Jaworowska, and Cifelli classification==
Several important fossil mammal discoveries have been made that have led researchers to question many of the relationships proposed by McKenna and Bell (1997). Additionally, researchers are subjecting taxonomic hypotheses to more rigorous [[cladistic]] analyses of early mammal fossils. Luo et al. (2002) summarized existing ideas and proposed new ideas of relationships among mammals at the most [[Basal (phylogenetics)|basal]] level. They argued that the term mammal should be defined based on characters (especially the dentary-squamosal jaw articulation) instead of a crown-based definition (the group that contains most recent common ancestor of [[monotreme]]s and [[theria]]ns and all of its descendants). Their definition of Mammalia is roughly equal to the [[Mammaliaformes]] as defined by McKenna and Bell (1997) and other authors. They also define their taxonomic levels as clades and do not apply [[Rank (zoology)|Linnean hierarchies]].
'''Mammalia'''
*†''[[Sinoconodon]]'' - earliest and most basal of mammals
*Unnamed clade 1 - a clade that contains all other mammals. These are characterized by [[determinant growth]] and occlusal features of the cheek teeth.
**†[[Morganucodontidae]] - morganucodontids, including †''[[Morganucodon]]'', †''[[Megazostrodon]]'', and others
**†[[Docodonta]] - docodonts, including †''[[Haldanodon]]'' and †''[[Castorocauda]]'' (Ji et al., 2006)
**Unnamed clade 2 - a clade containing all living mammals and some fossil relatives. It is characterized by the loss of a post[[dentary]] trough and a widened braincase.
***†''[[Hadrocodium]]''
***†''[[Kuenotherium]]''
***Crown-group [[Mammalia]] - the group that contains most recent common ancestor of [[monotreme]]s and [[theria]]ns and all of its descendants. This group is defined by additional characters relating the occlusion of [[Molar (tooth)|molar]]s and the presence of a well-developed [[masseteric fossa]].
****[[Australosphenida]] - a clade that contains [[monotreme]]s and their fossil relatives. These fossils include †''[[Ambondro]]'', †''[[Asfaltomylos]]'', †''[[Ausktribosphenos]]'', and †''Bishops''. If correct, this clade represents an independent evolution of the [[tribosphenic]] molar in [[Gondwana|southern continents]].
****[[Trechnotheria]] - [[Theria]]ns, [[Spalacotheriidae|spalacotheriids]] and their relatives. They are characterized by features of the [[scapula]], [[tibia]], and [[humerus]].
*****†[[Spalacotheriidae]] - including ''[[Akidolestes]]'', ''[[Zhangheotherium]]'', and ''[[Maotherium]]''.
*****[[Cladotheria]] - Therians, [[Dryolestidae|dryolestids]], and their relatives. They are characterized by features of the tribosphenic molar and the [[angular process]] of the [[dentary]].
******†[[Dryolestidae]]
******†''[[Amphitherium]]'' - ''[[incertae sedis]]'' (it may be a prototribosphenidan)
******[[Prototribosphenida]] - Therians and fossil relatives including †''[[Vincelestes]]''. Characterized by features of the [[cochlea]] including coiling.
*******†''[[Vincelestes]]''
*******[[Zatheria]] - Therians and fossil relatives including the "peramurids". Characterized by the presence of wear in the [[talonid]] of the lower molars.
********†"[[Peramuridae]]" - †''[[Peramus]]'' and relatives. Known only from preserved mandibles and distinctly zatherian molars.
********[[Boreosphenida]] - Therians and fossil relatives including †''[[Kielantherium]]''. They are characterized by molar features.
*********†''[[Kielantherium]]''
*********†[[Deltatheroida]] including †''[[Deltatheridium]]'' - ''incertae sedis'' (it may represent a metatherian)
*********Crown-group [[Theria]] - the group that contains most recent common ancestor of [[marsupial]]s and [[placental]]s and all of its descendants. Characterized by a host of molar features, aspects of the [[alispenoid]], and aspects of the [[talus bone|astragalus]] region.
****†[[Eutriconodonta]] - ''incertae sedis''. [[Triconodont]]s appear to be a member of the crown-Mammalia clade, but their relationships within it are unknown. It is also not certain that they represent a [[monophyly|monophyletic]] group. Examples include ''[[Repenomamus]]''.
***†[[Multituberculata]] - ''incertae sedis''. Luo e al. (2002) argue that multituberculates cannot be confidently placed in a particular clade of mammals. They suggest that they represent either basal mammals or are sister to the Trechnotheria.
==Classification system used in related articles==
In light of all the options available, the following classification system has been adopted for use in related articles.
===Subclass/Order [[Monotremata]]===
*Order [[Monotremata]]
**Family [[Tachyglossidae]]: echidnas
**Family [[Ornithorhynchidae]]: platypus
**Family [[Kollikodon]]tidae: ancient, extinct monotreme somewhat similar to platypus
===Subclass [[Marsupialia]]===
*Order [[Didelphimorphia]]
**Family [[Didelphidae]]: opossums
*Order [[Paucituberculata]]
**Family [[Caenolestidae]]: shrew or rat opossums
*Order [[Microbiotheria]]
**Family [[Microbiotheriidae]]: Monito del Monte
*Order [[Dasyuromorphia]]
**Family [[Thylacinidae]]: Thylacine
**Family [[Dasyuridae]]: marsupial carnivores
**Family [[Myrmecobiidae]]: Numbat
*Order [[Notoryctemorphia]]
**Family [[Notoryctidae]]: marsupial moles
*Order [[Peramelemorphia]]
**Family [[Peramelidae]]: bandicoots and bilbies
**Family [[Peroryctidae]]: rainforest bandicoots
*Order [[Diprotodontia]]
**Family [[Phascolarctidae]]: Koala
**Family [[Vombatidae]]: wombats
**Family [[Phalangeridae]]: cuscuses, brushtail possums
**Family [[Burramyidae]]: pygmy possums
**Family [[Tarsipedidae]]: Honey Possum
**Family [[Petauridae]]: striped possums, wrist-ringed gliders
**Family [[Pseudocheiridae]]: ringtailed possums and allies
**Family [[Potoroidae]]: potoroos, bettongs
**Family [[Acrobatidae]]: Feathertail Glider
**Family [[Hypsiprymnodontidae]]: Musky Rat Kangaroo
**Family [[Macropodidae]]: kangaroos, wallabies, and allies
===Subclass [[Placentalia]]===
*Order [[Xenarthra]]
**Family [[Bradypodidae]]: three-toed sloths
**Family [[Megalonychidae]]: two-toed sloths
**Family [[Cyclopedidae]]: silky anteaters
**Family [[Dasypodidae]]: armadillos
**Family [[Myrmecophagidae]]: true anteaters
*Superorder Glires
**Order [[Rodentia]]
***Suborder Sciurognathi
****Family [[Aplodontiidae]]: Mountain Beaver
****Family [[Sciuridae]]: squirrels, marmots
****Family [[Castoridae]]: beavers
****Family [[Geomyidae]]: pocket gophers
****Family [[Heteromyidae]]: pocket mice, kangaroo rats
****Family [[Dipodidae]]: jerboas, birch mice, jumping mice
****Family [[Muridae]]: rats and mice
****Family [[Anomaluridae]]: scaly-tailed squirrels
****Family [[Pedetidae]]: Springhaas
****Family [[Ctenodactylidae]]: gundis
****Family [[Gliridae]]: dormice
***Suborder Hystricognathi
****Family [[Diatomyidae]]: Laotian rock rat
****Family [[Bathyergidae]]: mole rats
****Family [[Hystricidae]]: Old World porcupines
****Family [[Petromuridae]]: Dassie Rat
****Family [[Thryonomyidae]]: cane rats
****Family [[Erethizontidae]]: New World porcupines
****Family [[Chinchillidae]]: chinchillas, viscachias
****Family [[Dinomyidae]]: Paracana
****Family [[Caviidae]]: cavies, guinea pigs, Patagonian Hare
****Family [[Hydrochoeridae]]: Capybara
****Family [[Dasyproctidae]]: agoutis, acouchis
****Family [[Agoutidae]]: pacas
****Family [[Ctenomyidae]]: tuco-tucos
****Family [[Octodontidae]]: viscacha rats, coruro
****Family [[Abrocomidae]]: chinchilla rats
****Family [[Echimyidae]]: spiny rats
****Family [[Capromyidae]]: hutias
****Family [[Myocastoridae]]: Nutria
**Order [[Lagomorpha]]
***Family [[Ochotonidae]]: pikas
***Family [[Leporidae]]: rabbits, hares
*Superorder [[Euarchonta]]
**Order [[Primates]]
***Suborder [[Strepsirrhini]]
****Family [[Cheirogaleidae]]: dwarf and mouse lemurs
****Family [[Lemuridae]]: lemurs
****Family [[Lepilemuridae]]: sportive lemurs
****Family [[Indriidae]]: indrid lemurs, sifakas
****Family [[Daubentoniidae]]: Aye-aye
****Family [[Lorisidae]]: lorises, Potto
****Family [[Galagidae]]: galagos
***Suborder [[Haplorrhini]]
****Family [[Tarsiidae]]: tarsiers
****Family [[Cebidae]]: marmosets, tamarins, capuchins and squirrel monkeys
****Family [[Aotidae]]: night or owl monkeys (douroucoulis)
****Family [[Pitheciidae]]: titis, sakis and uakaris
****Family [[Atelidae]]: howler, spider and woolly monkeys
****Family [[Cercopithecidae]]: Old World monkeys
****Family [[Hylobatidae]]: gibbons, siamangs
****Family [[Hominidae]]: Gorilla, chimpanzees, Orangutan, Human
**Order [[Scandentia]]: tree shrews
***Family [[Tupaiidae]]
***Family [[Ptilocercidae]]
**Order [[Dermoptera]]
***Family [[Cynocephalidae]]: colugos
*Order [[Insectivora]]
**Family [[Solenodontidae]]: solenodons
**Family [[Nesophontidae]]: nesophontids
**Family [[Erinaceidae]]: hedgehogs, gymnures
**Family [[Soricidae]]: shrews
**Family [[Talpidae]]: moles and desmans
*Order [[Chiroptera]]
**Suborder Megachiroptera
***Family [[Pteropodidae]]: Old World fruit bats
**Suborder Microchiroptera
***Family [[Rhinopomatidae]]: mouse-tailed bats
***Family [[Craseonycteridae]]: Kitti's Hog-nosed Bat
***Family [[Emballonuridae]]: sac-winged or sheath-tailed bats
***Family [[Nycteridae]]: slit-faced bats
***Family [[Megadermatidae]]: false vampire bats
***Family [[Rhinolophidae]]: horseshoe bats
***Family [[Noctilionidae]]: fishing bats
***Family [[Mormoopidae]]: leaf-chinned bats
***Family [[Phyllostomidae]]: New World leaf-nosed bats
***Family [[Natalidae]]: funnel-eared bats
***Family [[Furipteridae]]: smoky bats
***Family [[Thyropteridae]]: disk-winged bats
***Family [[Myzopodidae]]: Sucker-footed Bat
***Family [[Vespertilionidae]]: common bats
***Family [[Mystacinidae]]: short-tailed bats
***Family [[Molossidae]]: free-tailed bats
*Order [[Carnivora]]
**Suborder Fissipedia
***Superfamily Caniformia
****Family [[Canidae]]: wolves, coyotes, foxes, jackals
****Family [[Procyonidae]]: raccoons, coatis, olingos, kinkajou
****Family [[Mustelidae]]: weasels, otters, badgers
****Family [[Ailuridae]]: red panda
****Family [[Mephitidae]]: skunks
****Family [[Ursidae]]: bears, Giant Panda
***Superfamily Feliformia
****Family [[Felidae]]: cats
****Family [[Herpestidae]]: mongooses
****Family [[Hyaenidae]]: hyenas, Aardwolf
****Family [[Viverridae]]: civets, genets, linsangs
****Family [[Nandiniidae]]: African palm civet
**Suborder Pinnipedia
***Superfamily Otarioidae
****Family [[Odobenidae]]: Walrus
****Family [[Otariidae]]: sea lions
***Superfamily Phocoidae
****Family [[Phocidae]]: seals
*Order [[Pholidota]]
**Family [[Manidae]]: pangolins
*Superorder Ungulata
**Order [[Afrosoricida]]
***Family [[Tenrecidae]]: tenrecs
***Family [[Chrysochloridae]]: golden moles
**Order [[Macroscelidea]]
***Family [[Macroscelididae]]: elephant shrews
**Order [[Tubulidentata]]
***Family [[Orycteropodidae]]: Aardvark
**Order [[Hyracoidea]]
***Family [[Procaviidae]]: hyraxes
**Order [[Proboscidea]]
***Family [[Elephantidae]]: elephants
**Order [[Sirenia]]
***Family [[Dugongidae]]: Dugong, Stellar Sea Cow
***Family [[Trichechidae]]: manatees
**Order [[Perissodactyla]]
***Family [[Equidae]]: horses, asses, zebras
***Family [[Tapiridae]]: tapirs
***Family [[Rhinocerotidae]]: rhinceroses
**Order [[Artiodactyla]]
***Suborder Suiformes (also known as [[Suina]])
****Family [[Suidae]]: pigs, warthogs
****Family [[Tayassuidae]]: peccaries
****Family [[Hippopotamidae]]: hippopotamuses
***Suborder Tylopoda
****Family [[Camelidae]]: camels, llamas, Vicuna
***Suborder Ruminantia
****Family [[Tragulidae]]: chevrotains
****Family [[Giraffidae]]: Giraffe, Okapi
****Family [[Moschidae]]: musk deer
****Family [[Cervidae]]: true deer
****Family [[Antilocapridae]]: Pronghorn
****Family [[Bovidae]]: antelope, sheep, goats, buffalo, bison, cattle
**Order [[Cetacea]]
***Suborder Mysticeti
****Family [[Balaenidae]]: Bowhead and right whales
****Family [[Balaenopteridae]]: rorquals
****Family [[Eschrichtiidae]]: Gray Whale
****Family [[Neobalaenidae]]: Pigmy Right Whale
***Suborder Odontoceti
****Family [[Delphinidae]]: oceanic dolphins
****Family [[Monodontidae]]: Narwhal, Beluga
****Family [[Phocoenidae]]: porpoises
****Family [[Physeteridae]]: sperm whales
****Family [[Platanistoidea]]: river dolphins
****Family [[Ziphiidae]]: beaked whales
==See also==
*[[Animal]]
*[[List of mammals]]
*[[List of prehistoric mammals]]
*[[Mammal]]
==References==
{{Wikibookspar|Dichotomous Key|Mammalia}}
*Ji, Q., Z.-X. Luo, C.-X. Yuan, A. R. Tabrum. 2006. A swimming mammaliaform from the Middle Jurassic and ecomorphological diversification of early mammals. Science, 311:1123-1127.
*Luo, Z.-X., Z. Kielan-Jaworowska, and R. L. Cifelli. 2002. In quest for a phylogeny of Mesozoic mammals. Acta Palaeontologica Polonica, 47:1-78.
*McKenna, Malcolm C., and Bell, Susan K. 1997. ''Classification of Mammals Above the Species Level.'' Columbia University Press, New York, 631 pp. ISBN 0-231-11013-8
*Nowak, Ronald M. 1999. ''Walker's Mammals of the World'', 6th edition. Johns Hopkins University Press, 1936 pp. ISBN 0-8018-5789-9
*Simpson, George Gaylord. 1945. "The principles of classification and a classification of mammals". ''Bulletin of the American Museum of Natural History'', '''85''':1–350. ([http://digitallibrary.amnh.org/dspace/handle/2246/1104 pdf version])
*Springer, Mark S., Michael J. Stanhope, Ole Madsen, and Wilfried W. de Jong. 2004. "Molecules consolidate the placental mammal tree". Trends in Ecology and Evolution, '''19''':430–438. ([http://www.zi.ku.dk/evolbiology/courses/ME04/7_9/springer200-phyl.pdf pdf version])
*Vaughan, Terry A., James M. Ryan, and Nicholas J. Capzaplewski. 2000. ''Mammalogy: Fourth Edition''. Saunders College Publishing, 565 pp. ISBN 0-03-025034-X (Brooks Cole, 1999)
*Wilson, Don E., and Deeann M. Reeder (eds). 1993. ''Mammal Species of the World''. Smithsonian Institution Press, 1206 pp. ISBN 1-56098-217-9
[[Category:Mammals|Mammal classification]]
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[[es:Taxonomía de los mamíferos]]
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[[hu:Az emlősök rendszerezése]]
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[[simple:Mammalia (taxonomy)]]
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[[zh-yue:哺乳動物分類表]]