Suidae

Suidae Temporal range: Oligocene–Holocene PreЄ Є O S D C P T J K Pg N
Red river hog (Potamochoerus porcus)
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Mammalia
Order:	Artiodactyla
Suborder:	Suina
Family:	Suidae Gray, 1821
Genera
Over 30 extinct genera, 6 extant, see text.

Suidae is a family of artiodactyl mammals commonly called "pigs", hogs, or boars. In addition to numerous fossil species, up to sixteen extant species are currently recognized, classified into between four and eight genera. The family includes the domestic pig, Sus scrofa domesticus or Sus domesticus, in addition to numerous species of wild pig, such as the babirusa Babyrousa babyrussa and the warthog Phacochoerus aethiopicus. All suids, or swine, are native to the Old World, ranging from Asia and its islands, to Europe, and Africa.

The earliest fossil suids date from the Oligocene epoch of Asia, and their descendants reached Europe during the Miocene.^[1] Several fossil species are known, and show adaptations to a wide range of different diets, from strict herbivory to possible carrion-eating (in Tetraconodon).^[2]

Physical characteristics

Suids belong to the order Artiodactyla, and are generally regarded as the living members of that order most similar to the ancestral form. Unlike most other members of the order, they have four toes on each foot, although they walk only on the middle two digits, with the others staying clear of the ground. They also have a simple stomach, rather than the more complex, ruminant, stomach found in most other artiodactyl families.^[3]

They are small to medium animals, varying in size from 58 to 66 cm (23 to 26 in) in length, and 6 to 9 kg (13 to 20 lb) in weight in the case of the pygmy hog, to 130–210 cm (4.3–6.9 ft) and 100–275 kg (220–606 lb) in the giant forest hog.^[4] They have large heads and short necks, with relatively small eyes and prominent ears. Their heads have a distinctive snout, ending in a disc-shaped nose. Suids typically have a bristly coat, and a short tail ending in a tassle. The males possess a corkscrew-shaped penis, which fits into a similarly shaped groove in the female's cervix.^[5][6][7]

Suids have a well-developed sense of hearing, and are vocal animals, communicating with a series of grunts, squeals, and similar sounds. They also have an acute sense of smell. Many species are omnivorous, eating grass, leaves, roots, insects, worms, and even frogs or mice. Other species are more selective and purely herbivorous.^[3]

Their teeth reflect their diet, and suids retain the upper incisors, which are lost in most other Artiodactyls. The canine teeth are enlarged to form prominent tusks, used for rooting in moist earth or undergrowth, and in fighting. They have only a short diastema. The number of teeth varies between species, but the general dental formula is: 1-3.1.2-4.33.1.2.3

Behaviour and reproduction

Wild boar feeding on carcass

Suids are intelligent and adaptable animals. Adult females (sows) and their young travel in a group (sounder; see List of animal names), while adult males (boars) are either solitary, or travel in small bachelor groups. Males generally are not territorial, and come into conflict only during the mating season.

Litter size varies between one and twelve, depending on the species. The mother prepares a grass nest or similar den, which the young leave after about ten days. Suids are weaned at around three months, and become sexually mature at 18 months. In practice, however, male suids are unlikely to gain access to sows in the wild until they have reached their full physical size, at around four years of age. In all species, the male is significantly larger than the female, and possesses more prominent tusks.^[3]

Classification

Bearded pig, (Sus barbatus)

Chleuastochoerus fossil skull

The complete list of living species, and a partial list of extinct genera known from the fossil record, extinct taxa marked with a dagger "†",^[2] are:

• Suidae
  • Subfamily †Cainochoerinae
    • Genus †Albanohyus
    • Genus †Cainochoerus
  • Subfamily †Hyotheriinae
    • Genus †Aureliachoerus
    • Genus †Chicochoerus
    • Genus †Hyotherium
    • Genus †Nguruwe (formerly placed in Kubanochoerinae)^[8][9]
    • Genus †Xenohyus
  • Subfamily †Listriodontinae^[8]
    • Tribe †Kubanochoerini
      • Genus †Kubanochoerus (junior synonyms Libycochoerus, Megalochoerus)
    • Tribe †Listriodontini
      • Genus †Eurolistriodon
      • Genus †Listriodon (junior synonym Bunolistriodon)
    • Tribe †Namachoerini
      • Genus †Lopholistriodon
      • Genus †Namachoerus
    • Tribe incertae sedis
      • Genus †Dicoryphochoerus
  • Subfamily Suinae
    • Tribe Babyrousini
      • Genus Babyrousa (Pleistocene to recent)
        • Species B. babyrussa Buru babirusa
        • Species †B. bolabatuensis Bola Batu babirusa
        • Species Babyrousa celebensis North Sulawesi babirusa
        • Species Babyrousa togeanensis Togian babirusa
    • Tribe †Hippohyini
      • Genus †Hippohyus (Miocene to Pleistocene)
      • Genus †Sinohyus (Miocene)
      • Genus †Sivahyus (Miocene to Pliocene)
    • Tribe Potamochoerini
      • Genus †Celebochoerus (Pliocene to Pleistocene)
      • Genus Hylochoerus (Pleistocene to recent)
        • Species Hylochoerus meinertzhageni giant forest hog
      • Genus †Kolpochoerus (Pliocene to Pleistocene) (junior synonyms Ectopotamochoerus, Mesochoerus, Omochoerus, Promesochoerus)
      • Genus Potamochoerus (Miocene to recent)
        • Species P. larvatus bushpig
        • Species P. porcus red river hog
      • Genus †Propotamochoerus (Miocene to Pliocene)
    • Tribe Suini
      • Genus †Eumaiochoerus (Miocene)
      • Genus †Hippopotamodon (Miocene to Pleistocene) (junior synonym Limnostonyx)
      • Genus †Korynochoerus (Miocene to Pliocene)
      • Genus †Microstonyx (Miocene)
      • Genus Sus (Miocene to recent)
        • Species S. ahoenobarbus Palawan bearded pig
        • Species S. barbatus Bornean bearded pig
        • Species S. bucculentus Heude's pig or Vietnamese warty pig
        • Species S. cebifrons Visayan warty pig
        • Species S. celebensis Celebes warty pig
        • Species S. heureni Flores warty pig
        • Species S. oliveri Mindoro warty pig
        • Species S. philippensis Philippine warty pig
        • Species S. scrofa (also called S. domesticus) domestic pig, wild boar
        • Species S. verrucosus Java warty pig
        • Species †S. strozzi
    • Tribe Phacochoerini
      • Genus †Metridiochoerus (Pliocene to Pleistocene)
      • Genus Phacochoerus (Pliocene to recent)
        • Species P. aethiopicus Cape, Somali or desert warthog
        • Species P. africanus common warthog
      • Genus †Potamochoeroides (Pliocene, possibly Pleistocene)
      • Genus †Stylochoerus (Pleistocene)
    • Tribe incertae sedis ^[10]
      • Genus Porcula
        • Species P. salvania pygmy hog
  • Subfamily †Tetraconodontinae
    • Genus †Conohyus
    • Genus †Notochoerus
    • Genus †Nyanzachoerus
    • Genus †Parachleuastochoerus
    • Genus †Sivachoerus
    • Genus †Tetraconodon (Miocene, Myanmar) ^[11]
      • Species †T. intermedius
      • Species †T. malensis
      • Species †T. minor
  • Subfamily incertae sedis
    • Genus †Chleuastochoerus^[9]
    • Genus †Hemichoerus
    • Genus †Hyosus
    • Genus †Kenyasus (formerly placed in Kubanochoerinae)^[9]
    • Genus †Schizochoerus^[9]
    • Genus †Sinapriculus^[9]

References

1. Palmer, D., ed. (1999). The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals. London: Marshall Editions. p. 269. ISBN 1-84028-152-9.
2. Savage, RJG, & Long, MR (1986). Mammal Evolution: an illustrated guide. New York: Facts on File. pp. 212–213. ISBN 0-8160-1194-X.
3. Cumming, David (1984). Macdonald, D., ed. The Encyclopedia of Mammals. New York: Facts on File. pp. 500–503. ISBN 0-87196-871-1. External link in |title= (help)
5. Bonnie S. Dunbar; M.G. O'Rand (29 June 2013). A Comparative Overview of Mammalian Fertilization. Springer Science & Business Media. pp. 330–. ISBN 978-1-4757-8982-9.
6. Peter G. G. Jackson; Peter D. Cockcroft (2007). Handbook of Pig Medicine. Elsevier Health Sciences. ISBN 0-7020-2828-2.
7. Virginia Douglass Hayssen; Ari Van Tienhoven (1993). Asdell's Patterns of Mammalian Reproduction: A Compendium of Species-specific Data. Cornell University Press. ISBN 0-8014-1753-8.
8. Maeva, J.O. (2009). "The differentiation of bunodont Listriodontinae (Mammalia, Suidae) of Africa: new data from Kalodirr and Moruorot, Kenya". Zoological Journal of the Linnean Society 157 (3): 653–678. doi:10.1111/j.1096-3642.2008.00525.x.
9. Maeva, J.O.; et al. (2010). "Phylogenetic relationships of the Suidae (Mammalia, Cetartiodactyla): new insights on the relationships within Suoidea". Zoologica Scripta 39 (4): 315–330. doi:10.1111/j.1463-6409.2010.00431.x.
10. Funk, S.M.; et al. (2007). "The pygmy hog is a unique genus: 19th century taxonomists got it right first time round". Molecular Phylogenetics and Evolution 45 (2): 427–436. doi:10.1016/j.ympev.2007.08.007. PMID 17905601.
11. Htike, T.; et al. (2005). "A revision of Tetraconodon (Mammalia, Artiodactyla, Suidae) from the Miocene of Myanmar and description of a new species". Paleontological Research 9 (3): 243–254. doi:10.2517/prpsj.9.243.