Pangolin - Scaly Animals

Pangolins are mammals of the order Pholidota. The one extant family, Manidae>, has three genera: Manis, which comprises four species living in Asia, Phataginus, which comprises two species living in Africa, and Smutsia, which comprises two species also living in Africa. These species range in size from 30 to 100 cm (12 to 39 in). A number of extinct pangolin species are also known.

Pangolins have large, protective keratin scales covering their skin; they are the only known mammals with this adaptation. They live in hollow trees or burrows, depending on the species. Pangolins are nocturnal, and their diet consists of mainly ants and termites which they capture using their long tongues. They tend to be solitary animals, meeting only to mate and produce a litter of one to three offspring which are raised for about two years. Pangolins are threatened by hunting (for their meat and scales) and heavy deforestation of their natural habitats, and are the most trafficked mammals in the world. Of the eight species of pangolin, four (Phataginus tetradactyla, P. tricuspis, Smutsia gigantea, and S. temminckii) are listed as vulnerable, two (Manis crassicaudata and M. culionensis) are listed as endangered, and two (M. pentadactyla and M. javanica) are listed as critically endangered on the International Union for Conservation of Nature Red List of Threatened Species.

Etymology

The name "pangolin" comes from the Malay word pengguling, meaning "something that rolls up".

Description

The physical appearance of a pangolin is marked by large, hardened, overlapping plate-like scales, which are soft on newborn pangolins, but harden as the animal matures. They are made of keratin, the same material of which human fingernails and tetrapod claws are made. The pangolin's scaled body is comparable to a pine cone or globe artichoke. It can curl up into a ball when threatened, with its overlapping scales acting as armor, while it protects its face by tucking it under its tail. The scales are sharp, providing extra defense from predators.

Pangolins can also emit a noxious-smelling chemical from glands near the anus, similar to the spray of a skunk. They have short legs, with sharp claws which they use for burrowing into termite and ant mounds, as well as climbing.

The tongues of pangolins are extremely long like those of the giant anteater and the tube-lipped nectar bat; the root of the tongue is not attached to their hyoid bone, but is located in the thorax between the sternum and the trachea. Large pangolins can extend their tongues as much as 40 cm (16 in), with a diameter of only 0.5 cm (0.20 in).

Behavior

Most pangolins are nocturnal animals that use their well-developed sense of smell to find insects. The long-tailed pangolin is also active by day, while other species of pangolins spend most of the daytime sleeping, curled up into a ball.

Arboreal pangolins live in hollow trees, whereas the ground-dwelling species dig tunnels underground, to a depth of 3.5 m (11 ft).

Some pangolins walk with their front claws bent under the foot pad, although they use the entire foot pad on their rear limbs. Furthermore, some exhibit a bipedal stance for some behaviors and may walk a few steps bipedally. Pangolins are also good swimmers.

Diet

Pangolins are insectivorous. Most of their diet consists of various species of ants and termites and may be supplemented by other insects, especially larvae. They are somewhat particular and tend to consume only one or two species of insects, even when many species are available to them. A pangolin can consume 140 to 200 g (4.9 to 7.1 oz) of insects per day.

Pangolins have a very poor sense of vision, so rely heavily on smell and hearing. They use their powerful front claws to dig into trees, ground, and vegetation to find prey, then proceed to use their long tongues to probe inside the insect tunnels and retrieve their prey. Pangolins lack teeth, so also lack the ability to chew; however, they ingest small stones while foraging, which accumulate in their stomachs to help to grind up ants.

Some species, such as the tree pangolin, use their strong, prehensile tails to hang from tree branches and strip away bark from the trunk, exposing insect nests inside.

Reproduction

Pangolins are solitary and meet only to mate. Males are larger than females, weighing up to 40% more. While mating season is defined, they typically mate once each year, usually during the summer or autumn. Rather than the males seeking out the females, males mark their location with urine or feces and the females will find them. If there is competition over a female, the males will use their tails as clubs to fight for the opportunity to mate with her.

Gestation periods differ by species, ranging from roughly 70 to 140 days. African pangolin females usually give birth to a single offspring at a time, but the Asiatic species may give birth from one to three. Weight at birth is 80 to 450 g (2.8 to 15.9 oz) and the average length is 150 mm (5.9 in). At the time of birth, the scales are soft and white. After several days, they harden and darken to resemble those of an adult pangolin. During the vulnerable stage, the mother stays with her offspring in the burrow, nursing it, and wraps her body around it if she senses danger. The young cling to the mother's tail as she moves about, although in burrowing species, they remain in the burrow for the first two to four weeks of life. At one month, they first leave the burrow riding on the mother's back. Weaning takes place around three months of age, at which stage the young begin to eat insects in addition to nursing. At two years of age, the offspring are sexually mature and are abandoned by the mother.

Threats

Pangolins are hunted and eaten in many parts of Africa and are one of the more popular types of bush meat, while local healers use the pangolin as a source of traditional medicine. They are also in great demand in southern China and Vietnam because their meat is considered a delicacy and some believe that pangolin scales have medicinal qualities. Over the past decade, over one million pangolins are believed to have been illegally trafficked, making it the most trafficked animal in the world. This, coupled with deforestation, has led to a large decrease in the numbers of pangolins. Some species, such as Manis pentadactyla have become commercially extinct in certain ranges as a result of overhunting. In November 2010, pangolins were added to the Zoological Society of London's list of genetically distinct and endangered mammals. All eight species of pangolin are classified by the IUCN as threatened to extinction, while two are classified as critically endangered.

Though pangolins are protected by an international ban on their trade, populations have suffered from illegal trafficking due to unfounded beliefs in East Asia that their ground-up scales can stimulate lactation or cure cancer or asthma. In the past decade, numerous seizures of illegally trafficked pangolin and pangolin meat have taken place in Asia. In one such incident in April 2013, 10,000 kg (11 short tons) of pangolin meat were seized from a Chinese vessel that ran aground in the Philippines. In another case in August 2016, an Indonesian man was arrested after police raided his home and found over 650 pangolins in freezers on his property.

Conservation

As a result of increasing threats to pangolins, mainly in the form of illegal, international trade in pangolin skin, scales, and meat, these species have received increasing conservation attention in recent years. For example, in 2014, the IUCN recategorised all eight species of pangolin on its Red List of Threatened Species, and each species is now properly listed as being threatened with extinction. Also, the IUCN SSC Pangolin Specialist Group launched a global action plan to conserve pangolins, dubbed Scaling up Pangolin Conservation in July 2014. This action plan aims to improve all aspects of pangolin conservation with an added emphasis on combating poaching and trafficking of the animal, while educating communities in its importance.

Many attempts have been made to reproduce pangolins in captivity, but due to their reliance on wide-ranging habitats and very particular diets, these attempts are often unsuccessful. They are susceptible to diseases such as pneumonia and the development of ulcers in captivity, complications which can lead to an early death. In addition, pangolins rescued from illegal trade often have a higher chance of being infected with parasites such as intestinal worms, further lessening their chance for rehabilitation and reintroduction to the wild. Recently, researchers have been able to improve artificial pangolin habitats to allow for reproduction of pangolins, providing some hope for future reintroduction of these species into their natural habitats.

Taxonomy

Pangolins were formerly classified with various other orders, for example Xenarthra, which includes the ordinary anteaters, sloths, and the similar-looking armadillos. Newer genetic evidence, however, indicates their closest living relatives are the Carnivora with which they form the clade Ferae. Some palaeontologists placed Ernanodonta in a separate suborder of Cimolesta near Pholidota, have classified the pangolins in the order Cimolesta, together with several extinct groups indicated (†) below, though this idea has fallen out of favor since cimolestids have been determined to have not been placental mammals. A recent study has supported close affinities between pangolins and the Creodonta, Oxyaenidae and Hyaenodonta,.

Until recently, all species of pangolin had been attributed to the genus Manis. Recent research has supported the splitting of pangolins into three genera: Manis, Phataginus, and Smutsia.

• ORDER PHOLIDOTA
  • Genus †Arcticanodon dawsonae Rose, Eberle & McKenna 2004
  • Genus †Melaniella timosa Fox 1984
  • Genus †Molaetherium Heissig 1982
  • Family †Escavadodontidae Rose & Lucas 2000
    • Genus †Escavadodon zygus Rose & Lucas 2000
  • Family †Epoicotheriidae Simpson 1927
    • Genus †Amelotabes simpsoni Rose 1978
    • Genus †Alocodontulum atopum (Rose, Bown & Simons 1977) Rose, Bown & Simons 1978 [Alocodon Rose, Bown & Simons 1977 non Thulborn 1973; Alocodon atopum Rose, Bown & Simons 1977; Tubulodon atopum (Rose, Bown & Simons 1977) Rose et al. 1991]
    • Genus †Auroratherium sinense Tong & Wamg 1997
    • Genus †Pentapassalus Gazin 1952
      • Species †P. pearcei Gazin 1952 [Tubulodon pearcei (Gazin 1952) Rose et al. 1991]
      • Species †P. woodi (Guthrie 1967) Rose 1978 [Palaeanodon woodi Guthrie 1967; Tubulodon woodi (Guthrie 1967) Rose et al. 1991]
    • Genus †Dipassalus oryctes Rose, Krishtalka & Stucky 1991
    • Genus †Tetrapassalus Simpson 1959a
      • Species †T. mckennai Simpson 1959a
      • Species †T. proius West 1973c
    • Genus †Epoicotherium unicum (Douglass 1904) Simpson 1927 [Xenotherium Douglass 1906 non Ameghino 1904; Pseudochrysochloris Turnbull & Reed 1967; Xenotherium unicum Douglass 1905; Pseudochrysochloris yoderensis Turnbull & Reed 1967]
    • Genus †Tubulodon taylori Jepsen 1932
    • Genus †Xenocranium pileorivale Colbert 1942
  • Family †Metacheiromyidae Wortman 1903
    • Genus †Propalaeanodon schaffi Rose 1979
    • Genus †Palaeanodon Matthew 1918
      • Species †P. parvulus Matthew 1918
      • Species †P. ignavus Matthew 1918
      • Species †P. nievelti Gingerich 1989
    • Genus †Brachianodon westorum Gunnell & Gingerich 1993
    • Genus †Mylanodon rosei Secord et al. 2002
    • Genus †Metacheiromys Wortman 1903
      • Species †M. marshi Wortman 1903 [Metacheiromys tatusia Osborn 1904]
      • Species †M. dasypus Osborn 1904 [Metacheiromys osborni Simpson 1931]
  • Genus †Argyromanis patagonica Ameghino 1904
  • Genus †Orthoarthrus mixtus Ameghino 1904
  • Genus †Euromanis krebsi (Storch & Martin 1994) Gaudin, Emry & Wible 2009 [Eomanis krebsi Storch and Martin 1994]
  • Suborder Eupholidota Gaudin, Emry & Wible 2009
    • Family †Eomanidae Storch 2003
      • Genus †Eomanis waldi Storch 1978
    • Family Patriomanidae Szalay & Schrenk 1998 sensu Gaudin, Emry & Pogue 2006
      • Genus †Cryptomanis gobiensis Gaudin, Emry & Pogue 2006
      • Genus †Patriomanis americana Emry 1970
    • Family Manidae Gray 1821
      • Genus †Necromanis Filhol 1893 [Leptomanis Filhol 1893; Necrodasypus Filhol 1893; Teutomanis Ameghino 1905; Galliaetatus Ameghino 1905]
        • Species †N. franconica (Quenstedt 1886) [Lutra franconica Quenstedt 1886]
        • Species †N. parva Koenigswald 1969
        • Species †N. quercyi Filhol 1893
        • Species †N. galliae
      • Subfamily Smutsiinae Gray 1873 (African pangolins)
        • Genus Phataginus Rafinesque 1821 [Phataginus Rafinesque 1815 (nomen nudum); Triglochinopholis Fitzinger 1872; Uromanis Pocock 1924]
          • Tree pangolin (P. tricuspis (Rafinesque 1821) Rafinesque 1821)
          • Long-tailed pangolin (P. tetradactyla (Linnaeus 1766))
        • Genus Smutsia Gray 1865 (African ground pangolins)
          • Giant pangolin (S. gigantea (Illiger 1815))
          • Ground pangolin (S. temmincki (Smuts 1832))
      • Subfamily Maninae Gray 1821
        • Genus Manis Linnaeus 1758 [Pholidotus Storr 1780; Quaggelo Frisch 1775; Pangolinus Rafinesque 1821; Pangolinus Rafinesque 1815 nomen nudum; Pangolin Gray 1873; Phatages Sundevall 1843] (Asiatic pangolins)
          • †M. hungarica Kormos 1934
          • †M. lydekkeri Trouessart
          • Asian giant pangolin (M. paleojavanica Dubois) †
          • Subgenus (Manis) Linnaeus 1758
            • Indian pangolin (M. crassicaudata Gray 1827)
            • Chinese pangolin (M. pentadactyla Linnaeus 1758)
          • Subgenus (Paramanis) Pocock 1924
            • Sunda pangolin (M. javanica Desmarest 1822)
            • Philippine pangolin (M. culionensis Elera 1915)

References

External links

• Pangolin: Wildlife summary from the African Wildlife Foundation
• Tree of Life of Pholidota
• National Geographic video of a pangolin
• Proceedings of the Workshop on Trade and Conservation of Pangolins Native to South and Southeast Asia (PDF)
•  Thomas, Oldfield; Lydekker, Richard (1911). "Pangolin". Encyclopædia Britannica (11th ed.). 
• The Phylogeny of Living and Extinct Pangolins (Mammalia, Pholidota) and Associated Taxa: A Morphology Based Analysis (PDF)