Peramelemorphia facts for kids
Quick facts for kids Peramelemorphia |
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| Clockwise from top-left: Long-nosed bandicoot, Southern brown bandicoot, Northern pig-footed bandicoot, and Greater bilby | |
Scientific classification  |
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| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Mammalia |
| Infraclass: | Marsupialia |
| Superorder: | Australidelphia |
| Order: | Peramelemorphia Ameghino, 1889 |
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The animal group called Peramelemorphia (pronounced pe-rə-mel-ih-MOR-fee-ə) includes amazing creatures like bandicoots and bilbies. All members of this group live only in Australia and New Guinea. Most of them have a special look: a plump body with an arched back, a long, pointed snout, very large upright ears, fairly long, thin legs, and a slender tail. Their size can be quite different, from about 140 grams (like a small apple) up to 4 kilograms (like a small dog). However, most species weigh around one kilogram.
Contents
Discovering Bandicoots and Bilbies
The Marsupial Family Tree Puzzle
Scientists have long been puzzled about where bandicoots and bilbies fit into the larger family tree of marsupials. It's like trying to solve a mystery with two clues that seem to point in different directions!
One clue comes from their teeth. Bandicoots have several pairs of small front teeth in their lower jaw. This feature is called polyprotodonty. It is also found in marsupial carnivores, like quolls and Tasmanian devils. This suggests bandicoots might be related to these meat-eating marsupials.
The other clue is found in their feet. Bandicoots have an unusual feature called syndactyly. This means their second and third toes are joined together. This is a common trait in marsupial herbivores, such as kangaroos, wombats, and possums. This foot structure makes bandicoots seem related to these plant-eating marsupials.
For a long time, scientists debated how these two clues could both be true. Did these features evolve separately? Or did they change over time in complex ways? Recent studies looking at their DNA (molecular investigations) suggest that bandicoots and bilbies are quite distant relatives from other marsupial groups. This makes their unique features even more interesting!
Who's Related to Whom Among Bandicoots?
Thanks to recent DNA studies, scientists now have a clearer idea of how the different types of bandicoots and bilbies are related. This helps them build a family tree for these animals.
The first big split in their family tree separates the bilbies (part of the Thylacomyidae family) from all other bandicoots. Bilbies are very unique and branched off very early in their history.
Next, the pig-footed bandicoots (Chaeropodidae family) branched off. Sadly, these interesting animals are now extinct.
The remaining groups belong to the Peramelidae family. This family includes most of the living bandicoots. This family is further divided into smaller groups, showing how different bandicoot species are connected. For example, the short-nosed bandicoots and long-nosed bandicoots are closely related to each other.
Ancient Bandicoots: A Look at Fossils
Scientists have found many fossils of modern bandicoots and bilbies from recent geological periods. But finding older fossil species has been a real treasure hunt! These fossils help us understand their long history.
The very first fossil bandicoot species was discovered in 1955. It was a piece of a lower jaw found in Central Australia. This fossil dated back to the Pliocene epoch, millions of years ago. This fossil, named Ischnodon australis, showed some similarities to bilbies.
Later, in 1976, another fossil tooth was found in Queensland. This tooth was also from the Pliocene. It looked like those of the Perameles bandicoots, so it was named Perameles allinghamensis.
A big discovery happened in 1995 at the famous Riversleigh fossil site. Scientists found the first Miocene-aged bandicoot there. It was named Yarala burchfieldi. This species was smaller than today's bandicoots and had very old-fashioned teeth. Later, a skull of Yarala burchfieldi was found. This was the first skull ever discovered for any fossil bandicoot! Because it was so different, scientists created a new family, Yaralidae, just for this unique animal.
More discoveries followed, including new species of Perameles from different sites in Australia. In 2006, an even older species of Yarala, named Yarala kida, was found in the Northern Territory. This fossil dated back to the late Oligocene. This suggests Yarala was a very ancient type of bandicoot.
Riversleigh continued to be a goldmine for fossils. Scientists found several skulls and jaws of a new group called Galadi. These bandicoots, like Galadi speciosus, had shorter snouts than modern bandicoots. This suggests they might have eaten more meat than their modern relatives, who eat a mix of things.
In 2013, a mouse-sized bandicoot called Bulungu palara was described from Riversleigh. This group also included Bulungu muirheadae. As of 2013, this was the oldest fossil bandicoot ever found, about 24 million years old!
Excitingly, in 2014, the oldest modern bandicoot and bilby fossils were found at Riversleigh. These fossils came from middle Miocene deposits, around 15 million years old. The ancient bandicoot, named Crash bandicoot after the famous video game character, was represented by a single upper jaw. The ancient bilby, named Liyamayi dayi, was known from just three teeth.
Scientists also reported the first evidence of sexual dimorphism (differences in size between males and females) in fossil bandicoots. This was seen in two new species from Riversleigh, named Madju variae and Madju encorensis. These species were closely related to modern bandicoots but did not fit into any modern family. What was really special about Madju variae was that scientists found fossils of different ages. This included young pouch babies all the way to adults. This allowed them to study how these ancient bandicoots grew. They learned that Madju variae developed slower than modern bandicoots, much more like a bilby. This suggests that the rapid development of modern bandicoots might have evolved later. This change likely happened after the middle Miocene, when Australia started to become much drier.
See also
In Spanish: Perameleformes para niños
- List of mammal genera
- List of recently extinct mammals
- List of prehistoric mammals
