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 and a ringed tail. Its head-to-body length is 51–63.5 cm (20.1–25.0 in) with a 28–48.5 cm (11.0–19.1 in) tail, and it weighs between 3.2 and 15 kg (7.1 and 33.1 lb). It is well adapted to climbing due to its flexible joints and curved semi-retractile claws.
The red panda was first formally described in 1825. The two currently recognised subspecies, the Himalayan and the Chinese red panda, genetically diverged about 250,000 years ago. The red panda's place on the evolutionary tree has been debated, but modern genetic evidence places it in close affinity with raccoons, weasels, and skunks. It is not closely related to the giant panda, which is a bear, though both possess elongated wrist bones or "false thumbs" used for grasping bamboo. The evolutionary lineage of the red panda (Ailuridae) stretches back around 25 to 18 million years ago, as indicated by extinct fossil relatives found in Eurasia and North America.
The red panda inhabits coniferous forests as well as temperate broadleaf and mixed forests, favouring steep slopes with dense bamboo cover close to water sources. It is solitary and largely arboreal. It feeds mainly on bamboo shoots and leaves, but also on fruits and blossoms. Red pandas mate in early spring, with the females giving birth to litters of up to four cubs in summer. It is threatened by poaching as well as destruction and fragmentation of habitat due to deforestation. The species has been listed as Endangered on the IUCN Red List since 2015. It is protected in all range countries.
Community-based conservation programmes have been initiated in Nepal, Bhutan and northeastern India; in China, it benefits from nature conservation projects. Regional captive breeding programmes for the red panda have been established in zoos around the world. It is featured in animated movies, video games, comic books and as the namesake of companies and music bands.
Contents
- Etymology
- Taxonomy
- Description
- Distribution and Habitat
- Bahvior and Ecology
- Threats
- Conservation
- Cultural Significance
Etymology
The name "panda" is thought to have originated from the red panda's local Nepali name पञ्जा pajā "claw" or पौँजा paũjā "paw".[3][4] In English, it was simply called "panda"; it became known as the "red panda" or "lesser panda" to distinguish it from the giant panda, which was formally described and named in 1869.[4] The genus name Ailurus is adopted from the ancient Greek word αἴλουρος (ailouros), meaning "cat".[5] The specific epithet fulgens is Latin for "shining, bright".[4][6]
Taxonomy
The red panda was described and named in 1825 by Frederic Cuvier, who gave it its current scientific name Ailurus fulgens. Cuvier's description was based on zoological specimens, including skin, paws, jawbones and teeth "from the mountains north of India", as well as an account by Alfred Duvaucel.[8][9] The red panda was described earlier by Thomas Hardwicke in 1821, but his paper was only published in 1827.[4][10] In 1902, Oldfield Thomas described a skull of a male red panda specimen under the name Ailurus fulgens styani in honour of Frederick William Styan who had collected this specimen in Sichuan.[2]
Subspecies and Species
The modern red panda is the only recognised species in the genus Ailurus. It is traditionally divided into two subspecies: the Himalayan red panda (A. f. fulgens) and the Chinese red panda (A. f. styani). The Himalayan subspecies has a straighter profile, a lighter coloured forehead and ochre-tipped hairs on the lower back and rump. The Chinese subspecies has a more curved forehead, a more sloping snout, a darker coat with a less white face and more contrast between the tail rings.[11]
In 2020, results of a genetic analysis of red panda samples showed that the red panda populations in the Himalayas and China were separated about 250,000 years ago. The researchers suggested that the two subspecies should be treated as distinct species. Red Pandas in southeastern Tibet and northern Myanmar were found to be part of styani, while those of southern Tibet were of fulgens in the strict sense.[12] DNA sequencing of 132 red panda faecal samples collected in Northeast India and China also showed two distinct clusters indicating that the Siang River constitutes the boundary between the Himalayan and Chinese red pandas.[13] They probably diverged due to glaciation events on the southern Tibetan Plateau in the Pleistocene.[14]
Phylogeny
The placement of the red panda on the evolutionary tree has been debated. In the early 20th century, various scientists placed it in the family Procyonidae with raccoons and their allies. At the time, most prominent biologists also considered the red panda to be related to the giant panda, which would eventually be found to be a bear. A 1982 study examined the similarities and differences in the skull between the red panda and the giant panda, other bears and procyonids, and placed the species in its own family Ailuridae. The author of the study considered the red panda to be more closely related to bears.[11] A 1995 mitochondrial DNA analysis revealed that the red panda has close affinities with procyonids.[15] Further genetic studies in 2005, 2018 and 2021 have placed the red panda within the clade Musteloidea, which also includes Procyonidae, Mustelidae (weasels and relatives) and Mephitidae (skunks and relatives).[16][17][18]
Fossil Record
The family Ailuridae appears to have evolved in Europe in either the Late Oligocene or Early Miocene, about 25 to 18 million years ago. The earliest member Amphictis is known from its 10 cm (4 in) skull and may have been around the same size as the modern species. Its dentition consists of sharp premolars and carnassials (P4 and m1) and molars adapted for grinding (M1, M2 and m2), suggesting that it had a generalised carnivorous diet. Its placement within Ailuridae is based on the grooves on the side of its canine teeth. Other early or basal ailurids include Alopecocyon and Simocyon, whose fossils have been found throughout Eurasia and North America dating from the Middle Miocene, the latter of which survived into the Early Pliocene. Both have similar teeth to Amphictis and thus had a similar diet.[19] The puma-sized Simocyon was likely a tree-climber and shared a "false thumb"—an extended wrist bone—with the modern species, suggesting the appendage was an adaptation to arboreal locomotion and not to feed on bamboo.[19][20]
Later and more advanced ailurids are classified in the subfamily Ailurinae and are known as the "true" red pandas. These animals were smaller and more adapted for an omnivorous or herbivorous diet. The earliest known true panda is Magerictis from the Middle Miocene of Spain and known only from one tooth, a lower second molar. The tooth shows both ancestral and new characteristics having a relatively low and simple crown but also a lengthened crushing surface with developed tooth cusps like later species.[21] Later ailurines include Pristinailurus bristoli which lived in eastern North America from the late Miocene to the Early Pliocene[21][22] and species of the genus Parailurus which first appear in Early Pliocene Europe, spreading across Eurasia into North America.[21][23] These animals are likely to be part of a sister taxon to the lineage of the modern red panda. In contrast to the herbivorous modern species, these ancient pandas were likely omnivores, with highly cusped molars and sharp premolars.[21][22][24]
The earliest fossil record of the modern genus Ailurus date no earlier than the Pleistocene and appears to have been limited to Asia. The modern red panda's lineage became adapted for a specialised bamboo diet, having molar-like premolars and more elevated cusps.[21] The false thumb would secondarily gain a function in feeding.[19][20]
Genomics
Analysis of 53 red panda samples from Sichuan and Yunnan showed a high level of genetic diversity.[25] The full genome of the red panda was sequenced in 2017. Researchers have compared it to the genome of the giant panda to learn the genetics of convergent evolution, as both species have false thumbs and are adapted for a specialised bamboo diet despite having the digestive system of a carnivore. Both pandas show modifications to certain limb development genes (DYNC2H1 and PCNT), which may play roles in the development of the thumbs.[26] In switching from a carnivorous to a herbivorous diet, both species have reactivated taste receptor genes used for detecting bitterness, though the specific genes are different.[27]
Description
The red panda's coat is mainly red or orange-brown with a black belly and legs. The muzzle, cheeks, brows and inner ear margins are mostly white while the bushy tail has red and buff ring patterns and a dark brown tip.[28][29][30] The colouration appears to serve as camouflage in habitat with red moss and white lichen-covered trees. The guard hairs are longer and rougher while the dense undercoat is fluffier with shorter hairs.[29] The guard hairs on the back have a circular cross-section and are 47–56 mm (1.9–2.2 in) long. It has moderately long whiskers around the mouth, lower jaw and chin. The hair on the soles of the paws allows the animal to walk in snow.[28]
The red panda has a relatively small head, though proportionally larger than in similarly sized raccoons, with a reduced snout and triangular ears, and nearly evenly lengthed limbs.[28][29] It has a head-body length of 51–63.5 cm (20.1–25.0 in) with a 28–48.5 cm (11.0–19.1 in) tail. The Himalayan red panda is recorded to weigh 3.2–9.4 kg (7.1–20.7 lb), while the Chinese red panda weighs 4–15 kg (8.8–33.1 lb) for females and 4.2–13.4 kg (9.3–29.5 lb) for males.[28] It has five curved digits on each foot, each with curved semi-retractile claws that aid in climbing.[29] The pelvis and hindlimbs have flexible joints, adaptations for an arboreal quadrupedal lifestyle.[31] While not prehensile, the tail helps the animal balance while climbing.[29]
The forepaws possess a "false thumb", which is an extension of a wrist bone, the radial sesamoid found in many carnivorans. This thumb allows the animal grip onto bamboo stalks and both the digits and wrist bones are highly flexible. The red panda shares this feature with the giant panda, which has a larger sesamoid that is more compressed at the sides. In addition, the red panda's sesamoid has a more sunken tip while the giant panda's curves in the middle. These features give the giant panda more developed dexterity.[32]
The red panda's skull is wide, and its lower jaw is robust.[28][29] However, because it eats leaves and stems, which are not as tough, it has smaller chewing muscles than the giant panda. The digestive system of the red panda is only 4.2 times its body length, with a simple stomach, no noticeable divide between the ileum and colon, and no caecum.[28]