Eurasian wild boar
ssp. scrofa, meridionalis, baeticus, majori, algira, attila, lybicus and nigripes (Western races);
sibiricus, ussuricus, coreanus, leucostymax, riukiuanus, taivanus and moupinensis (Eastern races);
davidi, cristatus and affinis (South Asian races); and vittatus (Malayan race).
Status: Least Concern
Did you know? The wild boar has the widest distribution of any suid in the world.
S. scrofa is the most widespread species of naturally occurring wild pigs (see map). Many of the more distinctive regional forms of these animals were originally described as full species, e.g., vittatus, cristatus, leucostymax, moupinensis, and meridionalis, respectively from Sumatra, India, Japan, China, and Sardinia. Later and more comprehensive taxonomic reviews have combined many of these taxa into one species, mostly on the recognition that the different forms of S. scrofa formed a stepped cline extending from western Europe to the far east and insular South-East Asia. This gradual change in morphological characteristics allowed the combination of the extreme forms on either side of the range (scrofa and vittatus) into one species.
This species is therefore characterized by significant levels of naturally occurring geographic/genetic variation, duly compounded by anthropogenic interferences per widespread releases (whether deliberate or accidental) of pure-bred, hybrid and domesticated variants originating from other parts of their wide range. An astonishingly large number of subspecies have therefore been proposed and recognized in the literature, some of which are clearly invalid. Any more precise analyses of the likely number of truly recognizable/differentiated subspecies is still a matter of debate and disagreement, given that anything from 4 to 25 subspecies have been recognized by different authors. Of these, Colin Groves undertook by far the most comprehensive review when proposing the recognition of at least 16 morphologically distinct populations of S. scrofa on the basis of external as well as craniometric characteristics. His work has since been challenged by Peter Genov who proposed recognition of only 4 subspecies based on similar craniometric analyses, but which analyses was flawed inasmuch as it did not include some of the most distinct populations of these animals. Nonetheless, Genov merged these subspecies into 4 broadly geographic groupings, thereby broadly mirroring Groves’ more comprehensive review; namely: ‘Western races’ or the ‘scrofa group’; ‘Indian races’ or ‘cristatus group’; ‘Eastern races’ or ‘leucomystax group’; and a ‘Sundaic race’ – ‘Sus vittatus’. We therefore follow Groves' taxonomy because of the strength and breadth of his analysis, and use of external characteristics (not incorporated in Genov’s analysis); whilst accepting that any new and additional (e.g. phylogenetic) data sets are most likely to both strengthen the case for recognising particular additional subspecies (or elevating some currently recognised subspecies to full species) or merging other, currently recognised subspecies. For example, Groves has also questioned whether all his subspecies are all variants of one species or a complex of several different species, and has recently proposed the elevation of both ‘vitattus’ and ‘moupinensis’ to full species status. Of these, ‘vittatus’ is more easily comprehensible, being not only morphologically and geographically distinguishable as the so-called ‘Indonesian Banded Pig’, occurring throughout the distal limits of S. scrofa’s range in S.E. Asia - viz: Peninsular Malaysia though Sumatra, Java and Bali (if curiously absent from Borneo and associated islets); whereas ‘S. moupinensis’ is apparently confined to Myanmar, Indochina, and south-eastern China (Fujian), and therefore also including the problematic ‘S. bucculentus (see separate chapter re. this species).
As if to complicate matters, Groves has also recently proposed recognition of two more species, namely: Sus chirodontus (Heude, 1888) from south-central China (including Kienté, Ningkua, Zhejiang, Shaanxi, Anhui, and also Korea), and Sus ussuricus (Heude, 1888) from Heilongjiang and Far East China and Russia. Similarly sharp boundaries between various other mainland Asia subspecies do not exist, especially given evidence of hybridization between salient forms (e.g. S. s. davidi and S. s. cristatus). However, until and if these are races formally described and elevated we retain the existing taxonomy for S. scrofa, as follows:
Subspecies and distribution
S. scrofa originally occurred from the British Isles in the extreme west, through Eurasia from southern Scandinavia to southern Siberia, extending as far east as Korea and Japan, and south-east into some of the Sunda Islands and Taiwan. In the south, the species ranged along the Nile Valley to Khartoum, and north of the Sahara in Africa, and more or less following the continental coasts of south, east, and south-east Asia. Within this range the species was absent only from extremely dry deserts, e.g. the driest regions of Mongolia and in China westward of Sichuan; and alpine zones, such as the high altitudes of Pamir and Tien Shan.
In recent centuries, the range of S. scrofa has changed dramatically because of hunting and changes in available habitat. The species disappeared from Great Britain in the 16th century, from Denmark in the 19th century, and was greatly reduced in range and numbers in the 20th century from areas as distant as Tunisia, Sudan, Germany and Russia. Following these severe declines, there were some slight population recoveries in Russia, Italy, Spain and Germany in the mid-20th century, and natural and assisted range expansions in Denmark and Sweden. The species has also been inadvertently reintroduced in various locations in the United Kingdom via escapees of mixed origin from commercial farming enterprises. Ex-S. scrofa stocks also occur as introduced feral populations in various other parts of the world, including Australia, New Zealand, the eastern Malay Archipelago, and in North, Central and South America, in all of which areas they are now generally recognised as a major pest.
The four major groupings of naturally occurring subspecies are distributed as follows:
Western races; at least six, but possibly as many as eight, subspecies
Sus scrofa scrofa Linnaeus, 1758 – N. Spain, N. Italy, France, Germany, Netherlands, Belgium, Denmark, Poland, Czech Republic, and Albania? The taxonomic status of animals in Austria, Switzerland, Slovenia, and Slovakia is unclear but presumably these populations are included in S. s. scrofa; as are the populations of Sweden, Norway, Finland and the Baltic states. However, restocking of once depleted populations, for example in Italy, has likely involved the introduction and mixing of this subspecies other subspecies, such as S. s. attila.
Sus scrofa meridionalis Forsyth Major, 1882 – Sardinia and Corsica, with the proviso recognition that the two population are very likely to be introduced or feral.
Sus scrofa baeticus Thomas, 1912 – This subspecies was originally described from Coto Doñana, Andalusia, southern Spain, and later merged with S. s. meridionalis. Unless evidence is found that these Italian and Spanish populations are the relics of a much larger formerly contiguous range, this subspecies should be kept as distinct.
Sus scrofa majori De Beaux & Festa, 1927 – Central and southern Italy.
Sus scrofa algira Loche, 1867 – Tunisia, Algeria, Morocco, coastward of the mountains or in the low montane areas.
Sus scrofa attila Thomas, 1912 – Hungary, Ukraine, central and south Belarus, Romania, Moldova, southern Russia towards the northern flank of the Caucasus, but not including the Transcaucasian countries of Georgia, Armenia, and Azerbaijan. The range possibly extends as far south as the Mesopotamian Delta in Iraq, in which case it would likely include western and southwestern Iran, and possibly the eastern parts of Turkey and Syria, where it borders with S. s. lybicus. Such a southern range could not be easily reconciled with a statement by Groves that 'the difference between pigs from north and south of the Caucasus is quite striking; Transcaucasian boars are certainly not attila'. This subspecies may also extend into central Asia and include Kazakhstan, Uzbekistan, and Turkmenistan, but no data exist to support this.
Sus scrofa lybicus Gray, 1868 – Turkey, Syria, Jordan, Israel, Palestine, Egypt, but also former Yugoslavia was included in its range, which would suggest that now Slovenia, Serbia, Croatia, Bosnia and Herzegovina, and Kosovo are within the range of this subspecies, although the exact boundaries are unclear. Pigs from Albania have been assigned to S. s. scrofa.
Sus scrofa nigripes Blanford, 1875 – The flanks of the Tianshan mountains in Kyrgyzstan and northwestern China (Xinjiang autonomous region). An animal photographed in Golestan, Iran looked like this subspecies.
Eastern races; at least five, but possibly up to seven, subspecies
Sus scrofa sibiricus Staffe, 1922 – Mongolia and Transbaikal (south and east of Lake Baikal).
Sus scrofa ussuricus Heude, 1888 – Far East Russia and the Manchurian region (Far East China). Korean populations were previously included in this subspecies, but based on new evidence, this taxon seems more similar to S. s. moupinensis.
Sus scrofa coreanus Heude, 1897 – Korean Peninsula. We keep this subspecies for now as it is distinct from S. s. ussuricus. It was recently proposed for inclusion in the species S. moupinensis.
Sus scrofa leucostymax Temminck, 1842 – Main islands of Japan (Honshu, Shikoku, Kyushu, Nakadori, Hiburijima, Tojima, Kushima and other smaller islands).
Sus scrofa riukiuanus Kuroda, 1924 – Iriomote, Ishigaki, Okinawa, Tokunoshima, Amamioshima and Kakerome Islands in the Ryukyu chain of islands, extreme south Japan; though some of these populations have hybridized with introduced domesticates.
Sus scrofa taivanus Swinhoe, 1863 – Taiwan.
Sus scrofa moupinensis Milne Edwards – Coastal China, south to Vietnam and west to Szechuan.
South Asian races; three races, none with precisely defined ranges
Sus scrofa davidi Groves, 1981 – The arid zone from eastern Iran to Gujarat, including Pakistan and NW India, and perhaps north to Tadjikistan.
Sus scrofa cristatus Wagner, 1839 – Himalayas south to central India and east to Indochina (north of the Kra Isthmus).
Sus scrofa affinis Gray, 1847 – Southern India and Sri Lanka.
Malayan race; one highly distinct race, though presumably genetically continuous with S. s. cristatus (above) in the northern limits of its range in Indochina:
Sus scrofa vittatus Boie, 1828 – Malaya, south of the Isthmus of Kra, the offshore islands of Terutai and Langkawi, Sumatra, Riau Archipelago, Java, Bali, and a range of smaller islands around these islands, including Babi, Bakong, Batam, Bawean, Bengkalis, Bintan Bulan, Bunguran, Cuyo, Deli, Durian, Enggano, Galang, Jambongan, Karimon (Riau Isl), Kundur, Lagong, Laut, Lingga, Lingung, Mapor ,Moro Kecil, N. Pagai, Nias, Panaitan, Payong, Penang, Pinie, Rupat, Siantan, Siberut , Simeulue, Singkep, Sugi, Sugi Bawa,Telibon, Tinggi, Tuangku, and the Tambelan Islands.
This is a moderate to large sized pig with a relatively short muzzle and no face warts. The species is sexually dimorphic with females about 80% the size of males. Head-body length 90–200 cm; shoulder height 55–110 cm; tail length 15–40 cm, weight 44–320 kg. Size varies significantly between subspecies. Generally speaking, S. scrofa follows Bergmann's rule, with smaller animals nearer the tropics and larger, smaller-eared ones in the north of its range.
The coat is coarse and bristly, and varies in color from brown to almost black, usually turning grayish with age. There are great regional differences in color, and nearly white animals are known from central Asia. Several subspecies have dense underwool. The face, cheeks, and throat are slightly grizzled with whitish hairs, becoming distinctly white or forming white bands in some subspecies. The back is rounded and the legs are relatively long, especially in northern subspecies. Young are born generally brown with a pattern of longitudinal darker brown stripes along their torso, known as livery. This pattern fades between the second and sixth month, and the juveniles reach adult coloration at one year of age. The head is long and pointed, without an obvious beard, warts, or facial tufts. The upper canines form tusks which curve out and upwards. The lower canines are kept sharp by rubbing against the upper canines. These canines measure about 20 cm in adult males, in exceptional cases even 30 cm. In females they are smaller.
There is significant geographic variation in S. scrofa.
Western races: The nominal subspecies S. s. scrofa has an adult male skull length between 363 and 406 mm, which further increases towards the border of its range with S. s. attila. The species is dull to dark brown or olive-grey, with copious dark-grey or red-brown underwool, and a noticeable mane, which is often long and thick. Bodyweight in S. s. scrofa varies significantly from 54 kg to over 200 kg in males, with sows being quite a bit smaller (44·6–61·4 kg). Towards Spain and Italy body size decreases gradually. In northern Spain, the mean body weight of 637 mature males and females was 74·3 kg and 55·3 kg, respectively. The mean body-head lengths of males and females were 154·4 cm and 142·2 cm, respectively. The subspecies S. s. meridionalis in southern Spain and the islands of Sardinia and Corsica is significantly smaller than S. s. scrofa, with mean skulls length for males between 307·8 mm and 327 mm. This subspecies is colored a dull olive-fawn, with sparse underwool, and mostly lacking a mane. There is obvious clinal variation from north-western Europe to southern Spain, and it is unclear where the boundary between S. s. scrofa and S. s. meridionalis is. In central and southern Italy, the subspecies S. s. majori subspecies is apparently smaller than S. s. scrofa with a higher and wider skull. Since the 1950s, it has hybridized extensively with introduced S. s. scrofa populations, which likely obscures morphological differences. Further south, in northern Africa, the subspecies S. s. algira is like S. s. scrofa but it has smaller teeth and a broader occiput. The coat of this subspecies is black with yellowish or reddish tips, dark brown underwool, and not much of a mane. S. s. attila is a very large subspecies, with skull length in males over 450 mm, relatively small teeth, but with M3 long, always over 40 mm. S. s. attila is usually light yellow-grey, with hair tips long and straw-yellow, copious brown underwool, and a long mane which extends to the loins. Recent information suggests that the subspecies is less distinct than previously thought and might overlap in size as well as chromosomal arrangement with S. s. scrofa. S. s. lybicus is a small, pale and almost maneless subspecies. S. s. nigripes is a light-colored subspecies with dark legs—usually paler behind—, a nearly white face and no mane. It has a very broad skull. Weights of boars from present-day Uzbekistan and southern Kazakhstan are given as 220–240 kg. Like S. s. scrofa, S. s. nigripes has 36 chromosomes, not the 38 that are usual for the species, but the translocation is different.
Eastern races: S. s. sibiricus is a fairly small pig with a relatively short face (short nasals and palate) compared to similar sized pigs. It has a very high skull with broad occiput. It also stands out for the shape of its lacrimal bone (as measured by the proportion between suture height of the lacrimal bone at the orbit and its lower suture length), which is 1·0 for males (n=7) and 0·87 for females (n=4). S. s. ussuricus is the largest subspecies of S. scrofa, with boars often weighing over 300 kg. It has a low-crowned skull and thick pelage which is yellowish-grey in winter and black in summer when the long, light hair tips have worn off. S. s. ussuricus has black legs, sharply paler on posterior surfaces. The face is black and has a clear mouth-gonion band. Adult males can weigh up to 320 kg. Initially, pigs from the Korean Peninsula had been included in S. s. ussuricus, but their small size and genetic as well morphological similarity to S. s. moupinensis, makes that affinity less likely. We presently retain this as a distinct subspecies S. s. coreanus, but recognize that it might well be included in S. s. moupinensis. S. s. leucomystax is a smallish, short-legged yellow-brown pig, with virtually no mane. There is a neat cline of diminishing size from north to south, but this apparently doesn't warrant further division of this subspecies. The island species S. s. riukiuanus is by far the smallest subspecies. On the basis of a small data set, there appears to be no sexual size difference; three males with third molars in wear averaged 263 mm, and three females 261 mm in "profile length", which presumably equals greatest skull length. Recent phylogenetic studies have shown that this species is more closely related to the mainland China form than to S. s. leucostymax from the main islands of Japan. This is also confirmed by studies of crania and mandibles which are quite distinct from S. s. leucostymax. S. s. riukiuanus is a prime candidate to be recognized as a full species. S. s. taivanus from Taiwan is a small black pig, with markings on the side of the snout, as judged from camera trap pictures. Measurements of mandibles show considerable overlap between S. s. taivanus and S. s. leucostymax, but with S. s. riukiuanus being quite distinct. The occiput in S. s. taivanus is shorter than in S. s. leucostymax with little overhang. S. s. moupinensis is a fairly small, yellowish (in south of range) or darker (in north), short-maned pig with a broad, high-crowned skull, from most of China and Vietnam. Elevation to full species status was recently proposed for this taxon.
South Asian races: The subspecies of India, Burma, and western Thailand, S. s. cristatus is a long-maned subspecies with a coat that is brindled black unlike S. s. davidi (see below). S. s. cristatus is more lightly built than European subspecies, and it has a larger and more pointed head, and smaller and more pointed ears. The plane of the forehead is straight, while it is concave in the European subspecies. S. s. cristatus differs little from S. s. moupinensis, but has a much longer mane which extends to the rump. It is darker than S. s. moupinensis. S. s. davidi is a small, light brown pig, with a long thick mane, and without any black on legs. Weights of boars from Tajikistan, which might be this subspecies, were reported as 74–144 kg, and occasionally up to 158 kg for males, and 71–123 for females. This subspecies belongs to the low-crowned pigs of the western part of S. scrofa's distribution range, range than to the eastern pigs of India, China and the rest of east and south-east Asia. S. s. affinis of southern India and Sri Lanka is larger than S. s. cristatus, overall black or occasionally dark-brown.
Malayan race: Sometimes referred to as the ‘banded pig’, S. s. vittatus of peninsular Malaysia and western Indonesia is a small, low-crowned, short-faced pig with very sparse pelage. It is generally brown or agouti colored with black legs, typically with a distinct whitish band extending from either side of the snout to the jowls (hence ‘banded pig’), and distinct mane. It has very sparse body hair and no under wool. There is a huge range of size and color throughout this region, but it is so sporadically distributed, with intermediates between the extremes, that it is impossible to divide it up. The species has shorter nasals and narrower occiput than S. s. cristatus. It also stands apart from all other S. scrofa subspecies by the shape of the lacrimal bone and the shape of the rear end of the palatum durum.
S. scrofa is an ecologically very adaptable species occurring habitats varying from closed natural and planted forests to open scrublands with some cover. In Europe, the species occurs in agricultural landscapes, as well as riverine and mountainous forests, where it reaches its highest densities in oak-dominated forests. In south-east Asia, S. scrofa is found in mature forests, secondary forests, gardens and plantations. It can reach very high densities in Dipterocarp forests during time of mast-fruiting. S. scrofa can cause considerable damage to agricultural fields. The animals generally avoid open fields but do enter them readily when crops are taller and thus provide cover.
S. scrofa is a typical omnivorous species. They eat almost anything they come across, including grass, nuts, berries, carrion, roots, tubers, refuse, insects, small reptiles. They are also known to predate on young deer and lambs, and, in India, have been observed to predate on chital Axis axis and to forcibly appropriate fresh kills from leopards. Vertebrate prey probably constitute an important part of the species' diet in some areas; though studies in Spain revealed that prey items (mostly birds and crayfish) made up only 4% of their diets. Snails and terrestrial arthropods were frequently found but take up less volume. The species causes considerable damage to croplands, with damage to permanent grassland being more frequent and more severe than damage to annual crops. S. scrofa is preyed on by a range of species, including wolves Canis lupus, Asiatic dhole Cuon alpinus, tiger Panthera tigris, leopard Panthera pardus, Eurasian lynx Lynx lynx and some larger reptiles, such as crocodiles (Crocodylus spp.) and pythons (Python spp).
Activity of S. scrofa is concentrated from dusk to dawn, with a primary resting period at night and a briefer rest during the early afternoon. In areas with high hunting pressure, a shift to more nocturnal activity has been observed. S. scrofa rests in tight groups with bodily contact. The resting places, used several times before being abandoned, are made of troughs lined with leaves and branches. Wallowing is a favorite activity. After wallowing, the wild boar rubs against trees and bushes, an activity that acts as a territorial marker.
Movements, home range and social organisation
Densities of S. scrofa vary widely depending on habitat quality and mortality rates. To give some examples, in Italy, densities are generally about 3–5 animals/100 km2, in Spain they range from 0·7–16·3 animals/100 km2, and in Switzerland they are about 10 animals/100 km2. In Malaysia, S. scrofa locally reaches population densities of 47·0 pigs/km2 at least during times of high food availability. Pig biomass at such times was estimated at between 1,346 and 1,837 kg/km2. A review of 54 density studies in western Eurasia, showed that in the geographical span of 37–60o N, the population densities of wild boar declined by three orders of magnitude, from 1 to 1000 individuals 100 km2. Mean January temperature and the vegetation productivity were the most important factors explaining the biogeographical variation in population densities of S. scrofa, with the impact of temperature being stronger than that of productivity. The presence of wolves had a weak limiting effect on population densities of wild boar at the biogeographical scale.
S. scrofa generally occurs in maternal families or sounders averaging 20, but up to 100 individuals having been reported; albeit perhaps in temporary associations. Adult males are usually solitary outside of the breeding season. Group structure changes with the coming and going of farrowing females, the migration of maturing males (usually when they reach around 4 years old) and the arrival of unrelated sexually active males. The species is an excellent swimmer, and pigs have been documented swimming between offshore islands up to 7 km apart.
S. scrofa has a gestation period of between 112 and 130 days. Broods of 5–7 juveniles and 8–9 ones are the common. Broods of 10–13 juveniles and 1–4 ones occur rarely. Piglets weigh between 750 and 1,000g at birth. Just prior to giving birth, the sows leave their social groups and construct well-developed nests in which to give birth or ‘farrow’, a process usually lasting between 2–3 hours. The sow and piglets remain in, or close to, the nest for 4–6 days, before rejoining their natal family groups, after which piglets will cross suckle between other lactating sows. Young are weaned at 3–4 months, and they will begin to eat solid foods, such as worms and grubs, after about 2 weeks. The young usually reach sexual maturity at 18 months. Breeding occurs year-round in the tropics, although in more temperate zone the young are born primarily in the spring.
In the Ukraine, about 80% of S. scrofa females reproduce annually. Their fertility rate is 7.21± 0.26 piglets, but during the first year of their life more than 50% of them die. Animals can live over 20 years in the wild, but populations are dominated by younger animals. For example, an Eurasian wild steppe population included 58.6% juveniles (the 1st year of life), 14.3% of yearlings (the 2nd year), and 11.5% of adult males and 15.6% of females.
If surprised or cornered, a boar (and particularly a sow with her piglets) can and will defend itself and its young with intense vigor. The male lowers its head, charges, and then slashes upward with his tusks. The female, whose tusks are not visible, charges with her head up, mouth wide, and bites.
Status and conservation
S. scrofa is listed by the IUCN as Least Concern; excepting for the subspecies riukiuanus which has sometimes been listed separately as ‘Vulnerable’. The species is abundant in many parts of its range, though populations have been severely reduced and fragmented in places where hunting intensity is high (for example in eastern and southeastern Asia). Although there is no global population estimate, numbers can be high in many places. At a global level, there are no major threats to the species. However, there are many threats at a more local level, principally habitat destruction and hunting pressure, either for food, sport or in reprisal for crop damage, particularly in areas near human habitation and, in some places, genetic contamination through interbreeding with free-ranging domesticated or feral pigs. We point out some areas of particular concern.
In the Ryukyu Islands, S. Japan, the endemic S. s. riukiuanus is internationally recognised as being seriously threatened throughout it extremely restricted and discontinuous range, and ostensibly protected by the Japanese Government as a national monument. Nonetheless, it is widely hunted for sport and in reprisal for crop damage, whereby the salient governmental autrhorities also pay bounties to farmers these animals. In various places in Indonesia, most notably in Java, deliberate attempts have been made in the past to eradicate wild pigs altogether by means of organized shooting parties and poisoning campaigns. However, despite many thousands of wild pigs being destroyed in this way, it is clear that this has had little lasting effect on these animals.
Wild pigs are also susceptible to a variety of highly contagious diseases which can decimate their populations. Such catastrophic crashes have been reported from Sri Lanka in 1989 due to swine fever, Honshu Island, Japan in 1877, which was possibly caused by hog cholera, and Iriomote Islands between 1976 and 1980, which was caused by severe skin disease (tentatively identified as sarcoptic mange). S. scrofa is also threatened by genetic contamination through contact with free-ranging domesticates. The traditional practice of rearing 'domestic' pigs in semi-wild conditions has resulted in their hybridizing with the wild boar populations.
Although introduced feral pigs are almost invariably regarded as major pests, some seemingly ‘ancient breeds’ are of particular scientific interest and/or socio-economic importance to local peoples. Most prominent amongst these are the diminutive wild pigs of the Andaman and Nicobar Islands; the former including the world’s smallest free-ranging wild pigs (with the exception of pygmy hogs, Porcula salvania), which occur in two distinct ‘long-snouted’ and ‘short-snouted’ morphotypes, and which constitute one of the most important food resources for the few remaining indigenous Onge, Jarawa and Sentinilese indigenous tribal societies. Whilst the Andamanese tribals are traditionally hunter-gatherers dependent on the continued hunting of the wild pigs and other species; both wild and domestic pigs are of the greatest cultural importance the Shompen tribals of the Nicobar Islands, who not only domestic pigs in large numbers, but have evolved one of the most complex ‘human-pig’ cultures found anywhere in the in the world. A similar situation exists in eastern Indonesia, Papua, and a range Micronesian and Macronesian islands, where domesticated S. scrofa (as well as domesticated S. celebensis) play a very important cultural role.
Text adapted from: Meijaard, E., J. P. d'Huart, and W. L. R. Oliver. 2011. Family Suidae (Pigs). Pages 248-291 in D. E. Wilson, and R. A. Mittermeier, editors. Handbook of the Mammals of the World. Vol 2. Hoofed Mammals. Lynx Edicions, Barcelona, Spain.
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