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Sculptures by Phyllis Bone



The Suina contains the earliest and most archaic artiodactyls.

There are 3 families alive today:

Family Suidae (pigs)

Family Tayassuidae (peccaries)

Family Hippopotamidae (hippopotamuses).

The features shared by this group are:

  • four-toed feet.
  • little extension of distal limb bones.
  • a short diastema.
  • canines, upper incisors & bunodont (low crowned) molars.
  • the pre-molars are often unmolarised.
  • a simple stomach.


XH19-4.1 Wart hog (Phacochoerus æthiopicus) skull.

The wart hog skulls show typical suid features. Both the upper and lower canines point upwards. The teeth are low-crowned relative to tylopod and ruminant artiodactyls.

A wart hog and piglet, East Africa.

Wart hogs use their tusks in defence, and will have to defend their young from attacks by the many canivores found on the African savannah.

Lateral toe reduction is less pronounced than in the peccaries.

A warthog feeding.

Pigs are generally omnivorous, and are commonly found in forested habitats. Pigs have been known to eat leaves, seeds, roots, fungus, fallen fruit, grass, insects, birds' eggs, lizards and small mammals. Also, pigs are commonly active at night.The wart hog is one exception, it grazes on the African savannah and feeds on roots. It is only active during the day and will spend the night in dens, usually the abandoned burrows of other animals.

The tusks are used for defence and in conflict between males. The more prominent upper canines are primarily for display. Most damage is inflicted by the sharper lower canines. The facial warts that give this pig its name help protect the face during these conflicts.

Two skulls of Sus scrofa, the domestic pig.

The differences between the two skulls are attributable to selective breeding by humans.


A babirusa (Babyrousa babyrussa) 'snuffling' along the ground.

Pigs have a superb sense of smell and can easily locate food buried underground. The lead edge of the snout is hardened and used to dig with. The tusks are not used for digging.

A babirusa.


XH19-21.2 Collared peccary (Tayassu tajacu) skull

Similar to pigs, peccaries differ from their close relatives in a few ways:

  • further reduction of the 2nd and 5th toes.
  • the upper canines point down.
  • the stomach of a peccary has 3 chambers.

The peccaries became separated from other swine by crossing to the New World in the Oligocene.

A collared peccary (Tayassu tajacu).

There are three living species of peccary, the rarest of which is the chacoan peccary of the Andes ( Catagonus wagneri), only 'discovered' in 1975. All three species of peccary alive today are fairly similar. They are all omnivorous, with a similar diet to the pigs in the Old World. Peccaries also have a very sensitive snout and they will use their tusk-like canines to cut roots.

Peccaries are found in a variety of habitats in their range extending throughout South America and the southern portion of North America, including scrub, grassland, tropical forest and thorn forest.

All species travel in herds of varying sizes and show cooperative defence.

The peccary is hunted for meat, but the greatest threat to its future is habitat loss.


A collared peccary.

Compare the general shape of the peccary above with that of the tapir, a perissodacyl also found in the forests of South and Central America. Both are stocky, with short legs and a blunt snout.



A hippoptamus (Hippopotamus amphibius) from Africa.

Hippopotamuses are rarely seen out of the water during the day but must leave their pools at night to graze. Because their broad lips are so efficient at grazing, the vegetation close to their pools is often completely removed, so hippopotamuses must often travel a few kilometres in search of food. They will often use and wear out the same path every night.

Hippos have short legs with broad, four-toed feet to support their substantial weight and prevent their feet sinking too deeply into the mud.

Most hippopotami, including extinct forms, belong to the genus Hippopotamus. Presently found only in Africa, Pleistocene hippos were found in Eurasia.


The skull shows typical hippopotamid features:

  • eyes set high in the skull (common in aquatic animals).
  • a deep lower jaw.
  • enlarged, tusk-like canines and incisors.

A pygmy hippo (Choeropsis liberiensis) yawning.


A hippopotamus paddling in an African lake.

Notice that the the ears, eyes and nostrils are all on the upper surface of the head, allowing the hippopotamus to survey its surroundings while exposing as little of its head as possible.

Hippos are found in pools, rivers and wallows during the day but emerge to graze at night. Hippopotamuses can walk along the bottom of rivers and pools on the tip of their feet. The smaller, more primitive pygmy hippo (Choeropsis liberiensis) is found in forested areas of west Africa.

Pygmy hippopotamuses spend less time in the water, but their sensitive skin is at less risk from the sun because they live in dense tropical forests.

A pygmy hippo.


The hippo is at risk from the effect of climate change on its watery refuge. If the African climate becomes drier the pools and rivers will dry up, leaving hippos homeless.

A hippo mother and calf.

Gestation lasts 240 days, and the calves are suckled for 8 months.

Male hippopotamuses hold territories where they keep 'harems' of females. Groups of males, their females and calves can number nearly 150 animals.

Pygmy hippos lead a solitary lifestyle. The only social group they will be found in is a mother with her calf.


Two pygmy hippopotamuses: