World’s first research reveals the mystery of marsupial moles living in the desert

Credit: Photo Mike Gillum, from Science Advances (2025). DOI: 10.1126/sciadv.ado4140
Hidden beneath the dunes, a mysterious creature is gliding across the sand.
This isn’t one of the giant worms of Arrakis from Frank Herbert’s science fiction epic Dune. Rather, it’s a marsupial mole, a mysterious small mammal found only in the Australian desert.
There are two closely related species of marsupial moles.
Notoryctes typhlops, or the southern marsupial mole, is found throughout the deserts of south-central Australia. It is also called Icharichari by the local indigenous Anangu people. Notoryctes caurinus, or the boreal marsupial mole, is found in the deserts of northwestern Australia. It is also called Kakaratulu by the local indigenous Martu people.
Until recently, it was almost impossible to study these elusive animals. But our recent research in Science Advances has finally begun to unravel the basis of their incredible “desert powers.”
rarely observed
Marsupial moles are small, about the length of a pencil, and weigh between 40 and 70 grams. They have cylindrical bodies, yellow hair, and limbs that protrude slightly from the sides.
Rather than building permanent tunnels like their namesakes in the northern hemisphere, they “swim” through the loose sands of the Australian desert.
Moles, which are marsupials, live underground and are rarely seen because they live in vast deserts. In fact, there are only a few sightings every 10 years.
New technology, new insights
New DNA techniques could provide a window into the lives of enigmatic species such as the marsupial mole, which cannot be effectively studied in the wild.
To this end, our team collaborated with the Australian Biological Tissue Collection at the South Australian Museum to obtain two small tissue samples from a southern marsupial mole that was frozen over a decade ago. .
From these, they extracted the very long DNA fragments needed to generate genome assemblies. It is a digital representation of all the bases or “letters” that make up the marsupial mole’s genetic code.
Because DNA contains both the instructions for how to create an organism’s traits and the record of its evolutionary history, we have been able to glean surprising insights into this mysterious species.
unique adaptation
Marsupial moles have a variety of unique adaptations to survive in harsh environments. For example, their eyes are small and located under the skin, making them functionally blind.
By comparing the eye gene sequences with those of related marsupials, researchers were able to show that the marsupial mole was the first to lose a key gene in the eye lens. Perhaps this happened because a clear image is not as important underground.
This was followed by the gene for the color-sensing cone cells in the retina. After the eye lost significant function, the last genes to be degraded were those active in rod cells, which are important in low-light conditions.
For surface-dwelling mammals, these changes can be harmful. But the gradual deterioration of the eye’s genes, occurring in the right order, allowed the marsupial mole ancestor to change gradually without compromising its adaptability.
This is a beautiful illustration of how both adaptations and disorders share a similar genetic basis and the boundaries between them are shaped by their background.
Other features
Sequencing the genome allowed researchers to study other traits in marsupial moles.
For example, we showed that a key gene involved in testicular shedding during puberty may also be degraded in this species. This may help explain why male marsupial moles do not have a scrotum and their testes are located on the abdominal wall.
They also discovered that the marsupial mole has two copies of the gene that codes for hemoglobin, the molecule that carries oxygen to red blood cells. This is important because sand has low oxygen levels and poor air movement.
Additionally, this duplicate hemoglobin gene is typically used in newborn mammals.
Because marsupial pouches already have a low-oxygen environment, marsupial moles have had to evolve ways to avoid suffocating their young. Increasing hemoglobin may help.
Tracing the evolutionary tradition of moles
The marsupial mole’s strange and unusual characteristics have for years frustrated attempts to determine exactly who its closest relatives actually are. But by sequencing its genome, we can now trace its evolutionary legacy.
To do this, we looked at a special type of DNA sequence called a retrotransposon.
These are short pieces of DNA that can make copies of themselves, inserted randomly throughout an animal’s genome and passed down through generations.
Our research revealed that marsupial moles are a sister group to bandicoots and bilbys, and carnivorous marsupials like the Tasmanian devil are distant relatives.
long term decline
Little is currently known about the population health of the marsupial mole. However, deserts are among the ecosystems most threatened by climate change.
With this in mind, we also sought to glean first insights into how marsupial mole populations have changed over time.
Using patterns of genetic diversity across the marsupial mole genome, we demonstrate that marsupial moles may have experienced a long-term decline in effective population size starting about 70,000 years ago We were able to show that the This is consistent with historical changes during the last glacial period and suggests that the decline is due to climate change rather than human action.
It is unclear exactly how tens of thousands of years of lost genetic diversity will affect the ability of marsupial moles to continue their record of adaptation to extreme environments.
However, these discoveries suggest that studying marsupial moles using genetic techniques will ensure that they are not lost to the sands of time like many other mammals in Australia. This highlights that new and broader efforts may be needed.
Presented by The Conversation
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Source: World’s first study reveals mysteries of desert marsupial moles (January 12, 2025) https://phys.org/news/2025-01-world-reveals-mysteries-marsupial- Retrieved from mole on January 12, 2025.html
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