Ailuridae is a

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

in the

mammal Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur or ...

order

Carnivora Carnivora is a Clade, monophyletic order of Placentalia, placental mammals consisting of the most recent common ancestor of all felidae, cat-like and canidae, dog-like animals, and all descendants of that ancestor. Members of this group are f ...

. The family consists of the

red panda The red panda (''Ailurus fulgens''), also known as the lesser panda, is a small mammal native to the eastern Himalayas and southwestern China. It has dense reddish-brown fur with a black belly and legs, white-lined ears, a mostly white muzzle ...

(the sole living representative) and its extinct relatives.

Georges Cuvier Jean Léopold Nicolas Frédéric, Baron Cuvier (; 23 August 1769 – 13 May 1832), known as Georges Cuvier, was a French natural history, naturalist and zoology, zoologist, sometimes referred to as the "founding father of paleontology". Cuvier ...

first described ''Ailurus'' as belonging to the raccoon family in 1825; this classification has been controversial ever since. It was classified in the raccoon family because of morphological similarities of the head, colored ringed tail, and other morphological and

ecological Ecology () is the study of the relationships between living organisms, including humans, and their physical environment. Ecology considers organisms at the individual, population, community, ecosystem, and biosphere level. Ecology overlaps wi ...

characteristics. Somewhat later, it was assigned to the

bear Bears are carnivoran mammals of the family Ursidae. They are classified as caniforms, or doglike carnivorans. Although only eight species of bears are extant, they are widespread, appearing in a wide variety of habitats throughout the Nor ...

family. Molecular

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

studies had shown that, as an ancient species in the order

, the red panda is relatively close to the American

raccoon The raccoon ( or , ''Procyon lotor''), sometimes called the common raccoon to distinguish it from other species, is a mammal native to North America. It is the largest of the procyonid family, having a body length of , and a body weight of ...

and may be either a monotypic family or a subfamily within the

procyonid Procyonidae is a New World family of the order Carnivora. It comprises the raccoons, ringtails, cacomistles, coatis, kinkajous, olingos, and olinguitos. Procyonids inhabit a wide range of environments and are generally omnivorous. Character ...

family. An in-depth

mitochondrial DNA Mitochondrial DNA (mtDNA or mDNA) is the DNA located in mitochondria, cellular organelles within eukaryotic cells that convert chemical energy from food into a form that cells can use, such as adenosine triphosphate (ATP). Mitochondrial D ...

population analysis study stated: "According to the fossil record, the Red Panda diverged from its common ancestor with bears about 40 million years ago." With this divergence, by comparing the

sequence In mathematics, a sequence is an enumerated collection of objects in which repetitions are allowed and order matters. Like a set, it contains members (also called ''elements'', or ''terms''). The number of elements (possibly infinite) is calle ...

difference between the red panda and the raccoon, the observed

mutation rate In genetics, the mutation rate is the frequency of new mutations in a single gene or organism over time. Mutation rates are not constant and are not limited to a single type of mutation; there are many different types of mutations. Mutation rates ...

for the red panda was calculated to be on the order of 10⁹, which is apparently an underestimate compared with the average rate in mammals. This underestimation is probably due to multiple recurrent mutations as the

divergence In vector calculus, divergence is a vector operator that operates on a vector field, producing a scalar field giving the quantity of the vector field's source at each point. More technically, the divergence represents the volume density of the ...

between the red panda and the raccoon is extremely deep. The most recent molecular-systematic DNA research places the red panda into its own independent family, Ailuridae. Ailuridae are, in turn, part of a trichotomy within the broad superfamily

Musteloidea Musteloidea is a superfamily of carnivoran mammals united by shared characters of the skull and teeth. Musteloids are the sister group of pinnipeds, the group which includes seals. The Musteloidea consists of the families Ailuridae (red pandas), ...

that also includes the

Procyonidae Procyonidae is a New World family of the order Carnivora. It comprises the raccoons, ringtails, cacomistles, coatis, kinkajous, olingos, and olinguitos. Procyonids inhabit a wide range of environments and are generally omnivorous. Character ...

(

s) and a group that further subdivides into the Mephitidae (

skunk Skunks are mammals in the family Mephitidae. They are known for their ability to spray a liquid with a strong, unpleasant scent from their anal glands. Different species of skunk vary in appearance from black-and-white to brown, cream or ginge ...

s) and

Mustelidae The Mustelidae (; from Latin ''mustela'', weasel) are a family of carnivorous mammals, including weasels, badgers, otters, ferrets, martens, minks and wolverines, among others. Mustelids () are a diverse group and form the largest family in ...

(

weasel Weasels are mammals of the genus ''Mustela'' of the family Mustelidae. The genus ''Mustela'' includes the least weasels, polecats, stoats, ferrets and European mink. Members of this genus are small, active predators, with long and slender bo ...

s); but it is not a

(Ursidae). Ailurids appear to have originated during the Late

Oligocene The Oligocene ( ) is a geologic epoch of the Paleogene Period and extends from about 33.9 million to 23 million years before the present ( to ). As with other older geologic periods, the rock beds that define the epoch are well identified but the ...

to Early

Miocene The Miocene ( ) is the first geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and means "less recen ...

in Europe. The earliest known member, ''

Amphictis ''Amphictis'' was an extinct genus of ailurid that existed from the Late Oligocene to the Middle Miocene with fossils found in Eurasia and North America with a total of nine described species. The interrelationships of the different species as w ...

'', was likely an unspecialised carnivore, based on its dentition. Ailurids subsequently dispersed into Asia and North America. The puma-sized ''

Simocyon ''Simocyon'' ("short-snouted dog") is a genus of extinct carnivoran mammal in the family Ailuridae. ''Simocyon'', which was about the size of a mountain lion, lived in the late Miocene and early Pliocene epochs, and has been found in Europe, Asi ...

'' found in Middle

-Early

Pliocene The Pliocene ( ; also Pleiocene) is the epoch in the geologic time scale that extends from 5.333 million to 2.58hypercarnivore A hypercarnivore is an animal which has a diet that is more than 70% meat, either via active predation or by scavenging. The remaining non-meat diet may consist of non-animal foods such as fungi, fruits or other plant material. Some extant examp ...

. Like modern red panda it had a "false thumb" to aid in climbing. Members of the subfamily Ailurinae, which includes the modern red panda as well as the extinct genera ''

Pristinailurus ''Pristinailurus bristoli'' is a fossil species in the carnivoran family Ailuridae, well-represented in the Hemphillian deposits at the Gray Fossil Site in Gray, Tennessee Gray is a census-designated place (CDP) in Washington County, Tennessee ...

'' and '' Parailurus'', developed a specialised dental morphology with blunted cusps, creating an effective grinding surface to process plant material.

Classification

The relationship of the Ailuridae with other carnivorans is shown in the following

phylogenetic tree A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological spec ...

, which is based on the molecular phylogenetic analysis of six genes in Flynn, 2005. In addition to ''Ailurus'', the family Ailuridae includes seven extinct genera, most of which are assigned to three subfamilies: Amphictinae, Simocyoninae, and Ailurinae. * Family Ailuridae J.E. Gray, 1856 ** Subfamily † Amphictinae ?Winge, 1896 *** †''

'' ?Pomel, 1853 **** †''Amphictis borbonica'' Viret, 1929 **** †''Amphictis ambigua'' (Gervais, 1872) **** †''Amphictis milloquensis'' (Helbing, 1936) **** †''Amphictis antiqua'' (de Blainville, 1842) **** †''Amphictis schlosseri'' Heizmann & Morlo, 1994 **** †''Amphictis prolongata'' Morlo, 1996 **** †''Amphictis wintershofensis'' Roth, 1994 **** †''Amphictis cuspida'' Nagel, 2003 **** †''Amphictis timucua'' J.A. Baskin, 2017 ** Subfamily †

Simocyoninae Simocyoninae is an extinct subfamily of Ailuridae (of which the only recent member is the red panda). The taxonomic history of this group was complicated, as researchers placed various fossil caniform genera into the subfamily. In addition to ''S ...

Dawkins, 1868 *** †''

Actiocyon ''Actiocyon'' was an extinct genus of ailurid that existed from the Middle Miocene of North America. The type species, ''Actiocyon leardi'', was described in 1947 by the American paleontologist Chester Stock. Description The holotype consist ...

'' Stock, 1947 **** †''Actiocyon parverratis'' Smith et al., 2016 **** †''Actiocyon leardi'' Stock, 1947 *** †''

Alopecocyon ''Alopecocyon'' was a small relative of the modern red panda. It weighed only about 11 lb (5 kg). It was closely related to ''Simocyon'', a larger member of its group. Its fossils have been found in France, Poland, and Slovakia S ...

'' Camp & Vanderhoof, 1940 **** †''Alopecocyon getti'' Mein, 1958 **** †''Alopecocyon goeriachensis'' (Toula, 1884) *** †'' Protursus'' Crusafont & Kurtén, 1976 **** †''Protursus simpsoni'' Crusafont & Kurtén, 1976 *** †''

'' Wagner, 1858 **** †''Simocyon primigenius'' (Roth & Wagner, 1854) **** †''Simocyon diaphorus'' (Kaup, 1832) **** †''Simocyon batalleri'' Viret, 1929 **** †''Simocyon hungaricus'' Kadic & Kretzoi, 1927 ** Subfamily

Ailurinae Ailurinae is a subfamily of Ailuridae (of which this is the only extant subfamily out of three). While it is represented by the extant genus '' Ailurus'', there were a handful of genera whose fossils have been found across the Holarctic region. T ...

J.E. Gray, 1843 *** †'' Magerictis'' Ginsburg et al., 1997 **** †''Magerictis imperialensis'' Ginsburg et al., 1997 *** Tribe Pristinailurini Wallace & Lyon, 2022 **** †''

'' Wallace & Wang, 2004 ***** †''Pristinailurus bristoli'' Wallace & Wang, 2004 **** †'' Parailurus'' Schlosser, 1899 ***** †''Parailurus anglicus'' (Dawkins, 1888) 'Parailurus hungaricus'' Kormos, 1935***** †''Parailurus tedfordi'' Wallace & Lyon, 2022 ***** †''Parailurus baikalicus'' Sotnikova, 2008 *** Tribe Ailurini **** ''

Ailurus The red panda (''Ailurus fulgens''), also known as the lesser panda, is a small mammal native to the eastern Himalayas and southwestern China. It has dense reddish-brown fur with a black belly and legs, white-lined ears, a mostly white muzzle ...

'' F. Cuvier, 1825 ***** ''Ailurus fulgens'' - Red panda ****** ''Ailurus fulgens styani'' Thomas, 1902 – Eastern red panda ****** ''Ailurus fulgens fulgens'' F. Cuvier, 1825 – Western red panda

Classification

References

Further reading