The term “bandicoot” is derived from the Telugu word for “pig rat”, which initially referred to a large rodent species, the greater bandicoot rat, from India and Sri Lanka.
Like other nocturnal mammals, peramelemorphs depend greatly on their senses of touch, smell, and hearing while hunting. Little is known about communication in Peramelemorphia. Many species possess a scent glands just posterior to the ears, which are present in both genders of some species (e.g., northern brown bandicoot) and only present in the males of others. These glands are used for marking territorial boundaries and during male-male competition for mates or territory. Males warn potential rivals with by making puffing sounds and exhibit aggression with open-mouthed fighting and chasing. Captive peramelemorphs have been observed to make “soft spitting noises” when threatened. A few species have calls, which can ranged from shrill alarm calls to low, huffing noises accompanied by barred teeth.
Communication Channels: visual ; acoustic ; chemical
Other Communication Modes: pheromones
Perception Channels: visual ; tactile ; acoustic ; chemical
There are a total of 22 recognized species within Peramelemorphia. According to the IUCN’s Red List of Threatened Species, 3 have recently gone extinct, 4 are classified as endangered, 2 are vulnerable, 1 is near threatened, 9 are of least concern, and the remaining 3 are data deficient. Species adapted to arid and semi-arid habitats have experienced significant declines since European settlement. A major threat to peramelemorphs is the changing of fire regimens for agriculture and grazing animals across Australia and New Guinea. As fire regimens change and grazing increases, ground cover becomes reduced and predation increases. In addition, the introduction of non-native species into Australia and New Guinea (e.g., cats, red foxes, dogs and dingos) has resulted in increased predation and resource competition. By occupying a wide variety of habitats and vegetation types, bandicoots and bilbies largely avoid competition. However, the introduction of sheep, cattle, and European rabbits has caused many species to become threatened, and in some cases extinct, due to increased competition for resources. Some introduced species carry diseases that can be transmitted peramelemorphs. For example, toxoplasmosis, which is fatal to many species of bandicoot, was first introduced by cats. The giant bandicoot, which is endangered, is hunted and sold as food by local people.
Recovery plans for some species within Peramelemorphia have been implemented. These plans include protecting wild populations and their habitats, maintaining captive populations, intensive control of predators, and enhancing community education and participation in local conservation efforts. In some cases, the reintroduction of of locally extinct species has been successful (e.g., eastern barred bandicoot). However, many species and the habitats they depend upon remain vulnerable and unprotected. Some species have insufficient habitat for population growth due to intrafamilial range overlap and inbreeding. Small population sizes increase a species risk of extinction caused by predation and hunting.
Peramelemorphia (bandicoots and bilbies) consists of 22 species that are divided among 8 genera and 3 families: Peramelidae (bandicoots and echymiperas), Chaeropodidae (pig-footed bandicoot), and Thylacomyidae (bilbies). They have a rodent-like appearance with short legs, a stocky body, a short neck, and a long, pointy nose. They are largely nocturnal, and possess a well-developed sense of smell and eyes that are well adapted for night vision. Most peramelemorphs have brownish-red or tan fur and are sometimes marked with stripes. Long, rabbit-like ears also characterize some species. They range in size from less than 100 grams to over 5 kilograms, though most are about the size of a rabbit or smaller. Peramelemorphs are omnivores that eat mainly insects, but also consume a variety of vegetable material and some vertebrates as well. They occupy a wide range of habitats throughout Australia, New Guinea, Tasmania and the surrounding islands.
Due to their rapid decline, peramelemorphs have little to no effect on humans. Bandicoots and bilbies have been found to venture into suburban areas digging up lawns and gardens in search of food. As a result, they are sometimes viewed as pests. Peramelemorphs carry ticks, mites, and fleas, which can be transmitted to domestic animals and humans. Some species carry diseases, such as coccidiosis and toxoplasmosis, that can also be transmitted to domestic animals and humans.
Negative Impacts: injures humans (causes disease in humans ); crop pest
Members of Peramelemorphia have little direct economic importance, however, the giant bandicoot is still hunted by natives for its high market value in the bushmeat trade and for its fur. It is estimated that the species sells for the equivalent of 6 U.S. dollars.
Positive Impacts: food ; body parts are source of valuable material
Although peramelemorphs may help control insect pest populations, none are considered keystone species. As omnivores that also eat plants, they may play an important role as seed dispersers. Bilbies are semifossorial and may help aerate soil by burrowing.
Peramelemorphs are host to a number of endoparasites including an array of protists and roundworms. For example, renal coccidiosis and toxoplasmosis, which is transmitted by cats and is fatal to peramelemorphs, are both caused by parasitic protozoa, and toxoplasmosis is considered a major threat to the persistence of eastern barred bandicoots by the International Union for Conservation of Nature. Various members of Peramelemorphia are also vulnerable to a number of ectoparasitic arthropods including mites, ticks, and fleas. Their solitary nature, however, may help reduce intraspecific transmission of parasites.
Ecosystem Impact: soil aeration
Commensal/Parasitic Species:
Peramelemorphs are omnivorous and eat a wide variety of invertebrates including ants, termites, insect larvae, earthworms, spiders and centipedes as well as plant matter such as bulbs, grasses and seeds. Some species supplement their diet with fungi, bird eggs and small vertebrates such as lizards and mice. Peramelemorphs forage by digging with their strong front claws and then using their long snout and tongue grab ahold of food items. While they can eat many different foods, each colony tends to show preference for one or two particular food types. This is most likely due to regional availability of each food type and helps reduce intraspecific competition for resources. Many members of the family Peramelidae are not obligate drinkers, as they acquire much of their hydration needs through their diet. Their front limbs are short and well-adapted for ground foraging and digging, and their dentition is ideally suited to a diet of plants and insects.
Primary Diet: carnivore (Insectivore ); herbivore (Folivore ); omnivore
Bandicoots and bilbies are mainly found throughout Australia, New Guinea, and the surrounding islands, with the eastern barred bandicoot and southern brown bandicoot also being found in Tasmania. It is believed that members of the subfamily Peroryctinae most likely originated and radiated in New Guinea. However, their origin is speculative due to a lack of fossil evidence. Only 2 out of the 11 species of peroryctine bandicoots, the rufous spiny bandicoot and the Seram bandicoot, are currently found outside of New Guinea having ranges that extend to the tip of Cape York and Seram Island, respectively. The northern brown bandicoot is the only perameline bandicoot that is found outside of Australia in Southern New Guinea.
Biogeographic Regions: australian (Native )
Other Geographic Terms: island endemic
Peramelemorphs occupy a wide range of habitats, with altitude and climatic differences heavily influencing the distribution of species. Members of the family Peramelidae inhabit a variety of ecosystems, ranging from deserts to subalpine grasslands to tropical lowland rainforests, while thylacomyids primarily live in arid areas. Eastern barred bandicoots and the now extinct pig-footed bandicoot prefer grassland habitats, golden bandicoots inhabit the Top End and Kimberly tropics of Australia, brown bandicoots live in more secluded forests and the only living species of bilby, the greater bilby, is a desert-dweller. By occupying a wide variety of habitats and vegetation types, bandicoots and bilbies largely avoid competition. In New Guinea, peramelemorphs (Peroryctinae) are distributed throughout a wide range of altitudes. However, several species may occur sympatrically at moderate altitudes. The northern brown bandicoot, giant bandicoot and most species of spiny bandicoots prefer lowland areas, though some may live as high as 2000 m. Mouse bandicoots, striped bandicoots and Raffray’s bandicoots are upland species and typically live at elevations above 1000 m. There is one known high altitude species, Seram bandicoots, that are only found at altitudes of around 1800 m.
Habitat Regions: temperate ; tropical ; terrestrial
Terrestrial Biomes: desert or dune ; savanna or grassland ; chaparral ; forest ; rainforest ; scrub forest ; mountains
Other Habitat Features: suburban ; agricultural
Bandicoots and bilbies live, on average, 1 to 2 years in the wild. While only 1 in 10 offspring usually survive, once they reach maturity life expectancy ranges from 2.5 to 3 years. In captivity, mean longevity for peramelemorphs is 2 to 4 years.
Members of the order Peramelemorphia are terrestrial, ground-dwelling mammals. They range from 15 cm in length (excluding tail) and 100 g in weight to 60 cm in length and 5 kg in weight. Their bodies are compact in size with relatively short tails compared to the length of their bodies, except in the case of the greater bilby, which possesses a long, brush-like tail. Peramelemorphs have short necks, elongate skulls, and long, tapered snouts. Their ears are upright and can range from being small and rounded to fairly large and pointy. Males are usually larger than females and are socially dominant.
The hind limbs of peramelemorphs are relatively long and exceptionally powerful. On the hind feet, the forth toe is the largest, while the bones of the second and third toes are fused, but still maintain separate claws (i.e., syndactyly). The front limbs are very short and well-adapted for ground foraging and digging. The first and fifth toes on the forefeet are either absent or lack claws if present. The second, third, and fourth toes have strong, flat claws for digging. They typically use their strong hind limbs to leap and hop through brushy habitats; however, when escaping danger they are able to run at a fast gallop. Their front and back legs work alternately. Characteristically, they land on hind and forefeet, and then take off with a push of their large hindfeet.
Members of the order Peramelemorphia can be most noticeably recognized by their unique marsupium, the pouch located on the venter used to carry immature young. Unlike teh marsupium of kangaroos and wallabies, the marsupium of peramelemorphs opens to the rear. Although this condition is present in some diprotodonts (e.g., wombats), it is probably uniquely derived in each lineage.
Peramelemorphs are omnivorous and their dentition is well-suited to a diet consisting of plants and insects. Unlike diprotodonts, which have only 2 lower incisors, peramelemorphs are polyprotodonts, having multiple lower incisors and anywhere from 4 to 5 upper incisors. Their incisors are flattened at the tips with the crown of the last lower incisor having two lobes. The canines are present and well-developed and they also have 3 premolars, which are narrow and pointed (plagialacoid) and 4 molars, which are tribosphenic or quadrate, in the upper and lower sets. This gives them the dental formula of 4-5/3, 1/1, 3/3, 4/4 = 46 or 48.
Other Physical Features: endothermic ; homoiothermic; bilateral symmetry
Sexual Dimorphism: male larger
Peramelemorphs have few native predators. The only significant natural predators to bandicoots and bilbies are owls, quolls, and dingos. However, feral and domestic cats, dogs, foxes and other introduced animals have come to pose a considerable threat to the persistence of many local populations. In the past, bandicoots could often be found in Australian suburbs, however, domestic animals have significantly reduced their population. To protect themselves from predators, bandicoots and bilbies make nests in shallow holes in the ground, which they line with leaf litter. Leaf litter helps hide them from predators and protects them from inclement weather. A few species have calls, which can ranged from shrill alarm calls to low, huffing noises accompanied by barred teeth.
Known Predators:
Anti-predator Adaptations: cryptic
Direct observations of mating in peramelemorphs are rare, however, based on behavioral data they are probably either polygynous or promiscuous, and females are polyestrous. Although peramelemorphs are solitary, male territories overlap with those of several females, and during mating season males spend a majority of their time searching for receptive females. Once they find an estrus female, they follow the potential mate until she is ready to be mounted. Females may mate with more than one male if the opportunity presents itself.
Mating System: polygynous ; polygynandrous (promiscuous)
Peramelemorphs are known for their accelerated breeding process, which enables a single female to give birth to as many as 16 young per year. Unlike all other marsupials, members of Peramelemorphia have a chorioallantoic placenta, which replaces the more typical yolk sac placenta a few days into gestation. Unlike the placenta found in 'true mammals', the placenta of peramelemorphs lacks villi, resulting in relatively shorter gestation when compared to 'true mammals', which developed the chorioallantoic placenta independently. Breeding can take place year-round for some genera, while others breed in the spring only. Day length, food availability, and weather conditions appear to have a significant impact on the timing of breeding in seasonal breeders. Year-round breeders occasionally show a decline in birthrate during times of food scarcity or drought. Gestation time is variable, from as little as 12.5 days in long-nosed bandicoots (among the shortest in any mammal) to about 14 days in several other species. Litters range in size from 2 to 5 offspring, but usually no more than 4 survive. Like other marsupials, young are altricial, weighing about 0.2 grams at birth. Immediately after birth, they crawl into their mother’s pouch and attach to a nipple. They leave the pouch after about 60 days, and are weaned in about 70 days. Females generally mate at about the time their previous litter leaves the pouch, so the weaning of one litter coincides with the birth of the next.
While the ranges of male and female peramelemorphs extensively overlap, females likely dictate distribution as they select and defend high-quality habitats for nesting and foraging. Many species have scent glands just posterior to the ears. Present in both genders, it is thought that these glands are used to mark territorial boundaries or during male-male competition for mates. While some species, such as northern brown bandicoots create terrestrial nests with an internal chamber, others, such as eastern barred bandicoots make several different kinds of nests, including subterranean chambers that are used during parturition.
Key Reproductive Features: iteroparous ; seasonal breeding ; year-round breeding ; gonochoric/gonochoristic/dioecious (sexes separate); sexual ; viviparous ; post-partum estrous
The accelerated reproductive cycle of Peramelemorphia results in minimal parental care to young. The unique placenta of peramelemorphs lacks villi, which reduces direct contact between mother and fetus. However, the umbilical cord remains attached for a few hours afterbirth to serve as a safety rope while young leave the uterus and crawl into the rear-opening marsupium. Juveniles may continue to live in the mother’s nest for some time after leaving the pouch, but it is not known if they remain in their mother's nest after weaning. There is no contact between mother and offspring after young leave the nest. Young peramelemorphs can reach reproductive maturity in as little as four months, however, only 11.5% of young survive to adulthood.
Parental Investment: altricial ; female parental care ; pre-hatching/birth (Provisioning: Female, Protecting: Female); pre-weaning/fledging (Provisioning: Female, Protecting: Female)
The order Peramelemorphia /pɛrəmɛlɪˈmɔːrfiə/ includes the bandicoots and bilbies. All members of the order are endemic to Australia-New Guinea and most have the characteristic bandicoot shape: a plump, arch-backed body with a long, delicately tapering snout, very large upright ears, relatively long, thin legs, and a thin tail. Their size varies from about 140 grams up to 4 kilograms,[1] but most species are about one kilogram.
The position of the Peramelemorphia within the marsupial family tree has long been puzzling and controversial. There are two morphological features in the order that appear to show a clear evolutionary link with another marsupial group: the type of foot, and the teeth. Unfortunately, these clear signposts point in opposite directions.[2]
All members of the order are polyprotodont (have several pairs of lower front teeth)—in the case of the Peramelemorphia, three pairs. This suggests that they have evolved within Dasyuromorphia (marsupial carnivores). On the other hand, they also have an unusual feature in their feet: the second and third toes are fused together. This condition is called syndactyly, and is characteristic of the Diprotodontia (the order of marsupial herbivores that includes kangaroos, wombats, possums, and many others).[3]
Attempts to resolve this puzzle include the view that the bandicoot group evolved from the carnivores, retaining the polyprotodont dentition, and independently evolving a syndactyl hind foot; the contrary view that syndactyly is so unusual that it is unlikely to have evolved twice and therefore the bandicoot group must have evolved from a possum-like diprotodont creature, and re-evolved its extra teeth. A third view suggests that the bandicoot group evolved from a primitive carnivore, developed the syndactylous hind foot as a specialisation for climbing, and the diprotodonts then split off and evolved the two-tooth jaw that gives them their name. Recent molecular level investigations do not so far appear to have resolved the puzzle, but do strongly suggest that whatever the relationship of the bandicoot group to the other marsupial orders may be, it is a distant one.[4]
Recent molecular analyses have resulted in a phylogenetic reconstruction of the members of Peramelemorphia with quite strong support. The most basal split separates Thylacomyidae (Macrotis) from all other bandicoots. Probably the next to diverge was the recently extinct Chaeropodidae (Chaeropus). The remaining taxa comprise the Peramelidae, which divides into subfamilies Peramelinae (Isoodon and Perameles) and a clade in which the Echymiperinae (Echymipera and Microperoryctes) form a sister group to Peroryctinae (Peroryctes):[4]
Peramelemorphia Thylacomyidae †Chaeropodidae Peramelidae Peramelinae Echymiperinae PeroryctinaeMany specimens of modern peramelemorphian (e.g. Perameles spp. and Isoodon spp.) have been recovered in the fossil record from Pleistocene and Holocene fossil localities.[5] However, very few fossil species have been recovered to date. The first species of fossil peramelemorphian was described by R. A. Stirton in 1955. The specimen Stirton described was a partial lower jaw from the Tirari Desert in Central Australia, Pliocene in age. The lower jaw morphology suggested a relationship with bilbies (Family Thylacomyidae), and was named Ischnodon australis.[6]
It was not until 1976 that Archer and Wade described the next fossil bandicoot. A single upper molar was recovered from the Bluff Downs fossil site, Allingham Formation, in northern Queensland, also Pliocene in age. The tooth was similar to that of species of Perameles, and was therefore named Perameles allinghamensis.[7]
In 1995, the first Miocene species was described from Riversleigh, and was named Yarala burchfieldi by Dr Jeannette Muirhead. The species was represented by several upper and lower jaws, which were smaller than any living bandicoots and had a very primitive dentition.[8] A skull was later recovered in 2000, the first for any fossil peramelemorphian to date. Features of the skull and dentition suggested that Yarala burchfieldi was distinct from other peramelemorphians, and for this reason, a new Superfamily Yaraloidea and Family Yaralidae were erected to classify this species.[9]
In 1997, Muirhead, Dawson and Archer described a new species of Perameles, Perameles bowensis, from teeth recovered from two Pliocene fossil localities, Bow and Wellington Caves.[10] The same species was later reported in 2000 from Chinchilla, Queensland, by Mackness and colleagues.[11] In 2002, Price described a new species Perameles, Perameles sobbei, from the Darling Downs (Pleistocene in age), south-eastern Queensland. This species was represented by a lower jaw and a few isolated lower molars.[12] Additional material were later described in 2005 from the same site, including upper molars.[13]
A second species of Yarala, Yarala kida, was described in 2006 by Schwartz. This species was recovered from Kangaroo Well, a late Oligocene site from the Northern Territory in Australia. This species is thought to be even more primitive than Yarala burchfieldi.[14]
The second fossil skull of any fossil peramelemorphian was also recovered from Miocene sites of Riversleigh. In fact, more than one skull of this new species was found (and several lower and upper jaws), and was significantly different from any other bandicoot to erect a new genus, Galadi. The species was named Galadi speciosus by Travouillon and colleagues. It was short-snouted unlike modern bandicoots suggesting that it was more carnivorous than its omnivorous modern relatives. Its relationship to other bandicoots is unclear, but it was likely to be less primitive than Yarala but more primitive than living bandicoots.[15] An additional three species of Galadi were later described in 2013 and named Galadi grandis, Galadi amplus and Galadi adversus.[16]
Gurovich et al. (2013) described a new species of mouse-sized bandicoot from Riversleigh and from Kutjamarpu, Southern Australia. The species, named Bulungu palara, is represented by a skull and several lower and upper jaws.[17] Two other species in this genus were also described from the Etadunna Formation in South Australia, Bulungu muirheadae which was the oldest fossil bandicoot recovered as of 2013 (about 24 million years old), and Bulungu campbelli.[18]
The oldest modern bandicoot (peramelid) and the oldest bilby (Thylacomyid) were later discovered by Travouillon et al., 2014 from Riversleigh World Heritage Area, from middle Miocene fossil deposits (around 15 million years old). The peramelid, Crash bandicoot, was named after the famous video game character and is only represented by a single upper jaw. The bilby, Liyamayi dayinamed after geologist and philanthropist Robert Day, is only known from 3 teeth (2 upper molar, 1 lower molar).[19]
The first record of sexual dimorphism (difference in size between males and females) in a fossil bandicoot was reported from two new species from Riversleigh (Travouillon et al. 2014). Named Madju variae and Madju encorensis, they are closely related to modern bandicoots, but do not fall in any modern family, as did Galadi and Bulungu. Instead they are classified as Perameloid, with all known Peremelemorphian, to the exclusion of Yaralids. Madju variae is also unusual in preserving an ontogenetic series (age series from pouch young to adult), the second of any fossil marsupial mammal in Australia. The study of this ontogenetic series lead researchers to think that Madju variae developed slow than modern bandicoots, much more like a bilby, and therefore the rapid development of modern bandicoots must have evolved after the middle Miocene, when Australia started to become more arid.[20]
{{cite journal}}: CS1 maint: multiple names: authors list (link) The order Peramelemorphia /pɛrəmɛlɪˈmɔːrfiə/ includes the bandicoots and bilbies. All members of the order are endemic to Australia-New Guinea and most have the characteristic bandicoot shape: a plump, arch-backed body with a long, delicately tapering snout, very large upright ears, relatively long, thin legs, and a thin tail. Their size varies from about 140 grams up to 4 kilograms, but most species are about one kilogram.
