Eastern Barred Bandicoot
Encyclopedia
The Eastern Barred Bandicoot (Perameles gunni) was once distributed across the Basalt Plains of south west Victoria
, and in Tasmania
. It is a small, rabbit sized marsupial weighing less than 1 kg with a short tail and three to four whitish bars across the rump. It lives for just two to three years and is not gregarious. Males occupy large home ranges compared to females and only consort with females for mating. This species is nocturnal. It emerges from its nest at dusk to forage for a variety of invertebrates including crickets, beetles and earthworm
s. During the day it rests in a grass-lined nest. When foraging, it uses its long nose to probe deep into the soil and then digs eagerly when it locates food. Females have 8 nipples and can produce a maximum of 5 young in one litter with an average of 2 to 3 young. Gestation lasts just 12 days—this is one of the shortest gestation periods of any mammal. Young are weaned at 55 days and emerged juveniles remain dependent upon the mother and forage with her until day 86. Given ideal conditions, females can have up to five litters per year although reproduction becomes depressed in summer and ceases altogether in times of drought.
Due to predation by introduced foxes and cats, along with land-clearing for farming practises, the Victorian
subspecies is critically endangered. Since 1989, eight reintroduction sites have been established across the bandicoot's former range. Unfortunately, populations at four sites are now extinct (Floating Islands Nature Reserve, Lanark, Cobra Killuc Wildlife Reserve and Lake Goldsmith Nature Reserve), functionally extinct at Woodlands Historic park, declining at Mooramong and increasing at Hamilton Community Parklands and Mount Rothwell. The last remaining wild population which was once found along the Grange Burn (a creek) in Hamilton
has also been declared extinct. The estimated population size for the Victorian Eastern Barred bandicoot is 150 individuals.
The Tasmania
n subspecies (P. g. gunni) is vulnerable to extinction.
(P. bougainville) and the Long-nosed Bandicoot
(P. Nastua). It is also closely related to the Desert Bandicoot of the same genus, but this species has become extinct. There are about 20 other Bandicoots in the same family, Peramelidae
. They share similar features of long pointed snouts, and small ears. The Bandicoots are closely related to the Bilbies, which share the same order, Peramelemorphia
. These are all from the infraclass Marsupialia, shared of course with other species such as koalas and kangaroos, which means they diverged from the other placental mammals about 100 million years ago.
All the species of this order are native to Australia and New Guinea; however it is unclear how closely related this order is to the rest of the marsupials. The bandicoots have two features that suggest separate and quite opposite ideas of their evolution. They have three pairs of lower front incisors, which would usually suggest evolution from the order Dasyuromorphia
, which consists of carnivorous marsupials; however, the bandicoot’s middle two digits are syndactylous, meaning they are joined together except for the claw. This would suggest they share the common ancestor of the Diprotodontia
which includes the kangaroos and koalas.
There are, of course, theories using these features to describe their evolution. The incisors could, in fact, be analogous features shared between the bandicoot and the Dasyuromorphia order. They share the same function, after all, and though they are structurally similar the incisors of the carnivorous marsupials are a lot sharper than the flatter versions in the Bandicoot. The Bandicoot may have evolved the third tooth separately. If this was the case, it would seem logical that the syndactyly feet were homologous features shared between the Bandicoots and the kangaroos, wombats, possums and other species. This would make sense as syndactyly is so rare it is unlikely that it would evolve twice in two separate populations. The feet of the bandicoot when compared, to say, the kangaroo are structurally quite similar. This similarity suggests that the bandicoots shared a more recent ancestor with them.
Nevertheless, though this idea is more likely, simply because of the rarity of syndactyly, it is possible that syndactyly evolved in the two different populations, and that bandicoots are actually more closely related to species such as the Tasmanian devils and the Numbat. This would mean the incisors were homologous features, structurally the same but with a slightly different function (as the carnivorous marsupials use them to rip through flesh), and the syndactyly hind feet are analogous features, as they are used for the same basic function but are not evidence of divergent evolution.
Molecular evidence does not prove or disprove any of these theories, or any other related theories that are not suggested here. It is not quite definitive where the bandicoot sits exactly in the tree of life, but whatever the case, it seems that the relationship between the bandicoots and bilbies with the other orders is a distant one.
, the main character of the best-selling Crash Bandicoot series of video games, is classified as an Eastern Barred Bandicoot.
Victoria (Australia)
Victoria is the second most populous state in Australia. Geographically the smallest mainland state, Victoria is bordered by New South Wales, South Australia, and Tasmania on Boundary Islet to the north, west and south respectively....
, and in Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
. It is a small, rabbit sized marsupial weighing less than 1 kg with a short tail and three to four whitish bars across the rump. It lives for just two to three years and is not gregarious. Males occupy large home ranges compared to females and only consort with females for mating. This species is nocturnal. It emerges from its nest at dusk to forage for a variety of invertebrates including crickets, beetles and earthworm
Earthworm
Earthworm is the common name for the largest members of Oligochaeta in the phylum Annelida. In classical systems they were placed in the order Opisthopora, on the basis of the male pores opening posterior to the female pores, even though the internal male segments are anterior to the female...
s. During the day it rests in a grass-lined nest. When foraging, it uses its long nose to probe deep into the soil and then digs eagerly when it locates food. Females have 8 nipples and can produce a maximum of 5 young in one litter with an average of 2 to 3 young. Gestation lasts just 12 days—this is one of the shortest gestation periods of any mammal. Young are weaned at 55 days and emerged juveniles remain dependent upon the mother and forage with her until day 86. Given ideal conditions, females can have up to five litters per year although reproduction becomes depressed in summer and ceases altogether in times of drought.
Due to predation by introduced foxes and cats, along with land-clearing for farming practises, the Victorian
Victoria (Australia)
Victoria is the second most populous state in Australia. Geographically the smallest mainland state, Victoria is bordered by New South Wales, South Australia, and Tasmania on Boundary Islet to the north, west and south respectively....
subspecies is critically endangered. Since 1989, eight reintroduction sites have been established across the bandicoot's former range. Unfortunately, populations at four sites are now extinct (Floating Islands Nature Reserve, Lanark, Cobra Killuc Wildlife Reserve and Lake Goldsmith Nature Reserve), functionally extinct at Woodlands Historic park, declining at Mooramong and increasing at Hamilton Community Parklands and Mount Rothwell. The last remaining wild population which was once found along the Grange Burn (a creek) in Hamilton
Hamilton, Victoria
Hamilton is a city in western Victoria, Australia. It is located at the intersection of the Glenelg Highway and the Henty Highway...
has also been declared extinct. The estimated population size for the Victorian Eastern Barred bandicoot is 150 individuals.
The Tasmania
Tasmania
Tasmania is an Australian island and state. It is south of the continent, separated by Bass Strait. The state includes the island of Tasmania—the 26th largest island in the world—and the surrounding islands. The state has a population of 507,626 , of whom almost half reside in the greater Hobart...
n subspecies (P. g. gunni) is vulnerable to extinction.
Phylogeny and Evolutionary Relationships
The Eastern Barred Bandicoot is most closely related to the other species of bandicoot in its genus, of which only two species are still extant today. These surviving relatives are the Western Barred BandicootWestern Barred Bandicoot
The Western Barred Bandicoot , also known as the Marl, is a small species of bandicoot found in Australia. It was once widespread across southern Australia from Western Australia to central New South Wales, but it is now found on Bernier, Dorre and Faure islands in Shark Bay, Western Australia,...
(P. bougainville) and the Long-nosed Bandicoot
Long-nosed Bandicoot
The Long-nosed Bandicoot is a species of bandicoot found in Australia. It is the largest member of its genus, which also includes the Western Barred Bandicoot, the Eastern Barred Bandicoot and the Desert Bandicoot....
(P. Nastua). It is also closely related to the Desert Bandicoot of the same genus, but this species has become extinct. There are about 20 other Bandicoots in the same family, Peramelidae
Peramelidae
Peramelidae is the family of marsupials that contains all of the extant bandicoots. One known extinct species of bandicoot, the Pig-footed Bandicoot, was so different than the other species that it was recently moved into its own family. There are four described fossil Peramelids...
. They share similar features of long pointed snouts, and small ears. The Bandicoots are closely related to the Bilbies, which share the same order, Peramelemorphia
Peramelemorphia
The order Peramelemorphia includes the bandicoots and bilbies: it equates approximately to the mainstream of marsupial omnivores...
. These are all from the infraclass Marsupialia, shared of course with other species such as koalas and kangaroos, which means they diverged from the other placental mammals about 100 million years ago.
All the species of this order are native to Australia and New Guinea; however it is unclear how closely related this order is to the rest of the marsupials. The bandicoots have two features that suggest separate and quite opposite ideas of their evolution. They have three pairs of lower front incisors, which would usually suggest evolution from the order Dasyuromorphia
Dasyuromorphia
The order Dasyuromorphia comprises most of the Australian carnivorous marsupials, including quolls, dunnarts, the numbat, the Tasmanian devil, and the recently extinct thylacine...
, which consists of carnivorous marsupials; however, the bandicoot’s middle two digits are syndactylous, meaning they are joined together except for the claw. This would suggest they share the common ancestor of the Diprotodontia
Diprotodontia
Diprotodontia is a large order of about 120 marsupial mammals including the kangaroos, wallabies, possums, koala, wombats, and many others. Extinct diprotodonts include the rhinoceros-sized Diprotodon, and Thylacoleo, the so-called "marsupial lion"....
which includes the kangaroos and koalas.
There are, of course, theories using these features to describe their evolution. The incisors could, in fact, be analogous features shared between the bandicoot and the Dasyuromorphia order. They share the same function, after all, and though they are structurally similar the incisors of the carnivorous marsupials are a lot sharper than the flatter versions in the Bandicoot. The Bandicoot may have evolved the third tooth separately. If this was the case, it would seem logical that the syndactyly feet were homologous features shared between the Bandicoots and the kangaroos, wombats, possums and other species. This would make sense as syndactyly is so rare it is unlikely that it would evolve twice in two separate populations. The feet of the bandicoot when compared, to say, the kangaroo are structurally quite similar. This similarity suggests that the bandicoots shared a more recent ancestor with them.
Nevertheless, though this idea is more likely, simply because of the rarity of syndactyly, it is possible that syndactyly evolved in the two different populations, and that bandicoots are actually more closely related to species such as the Tasmanian devils and the Numbat. This would mean the incisors were homologous features, structurally the same but with a slightly different function (as the carnivorous marsupials use them to rip through flesh), and the syndactyly hind feet are analogous features, as they are used for the same basic function but are not evidence of divergent evolution.
Molecular evidence does not prove or disprove any of these theories, or any other related theories that are not suggested here. It is not quite definitive where the bandicoot sits exactly in the tree of life, but whatever the case, it seems that the relationship between the bandicoots and bilbies with the other orders is a distant one.
Cultural impact
Crash BandicootCrash Bandicoot (character)
Crash Bandicoot, or simply Crash, is a video game character and the primary protagonist of the Crash Bandicoot series of video games. Introduced in the 1996 video game Crash Bandicoot, Crash is an Eastern Barred Bandicoot that was genetically enhanced by the series antagonist Doctor Neo Cortex and...
, the main character of the best-selling Crash Bandicoot series of video games, is classified as an Eastern Barred Bandicoot.
External links
- ARKive - images and movies of the Eastern barred bandicoot (Perameles gunnii)
- Dept of Sustainability & Environment (Victoria) - Eastern Barred Bandicoot
- Parks & Wildlife Service (Tasmania) - Threatened Species - Eastern Barred Bandicoot
- Hamilton Community Parklands Eastern Barred Bandicoot Management Plan