In collaboration with Indigenous rangers and conservation managers, scientists from the University of Sydney and elsewhere have decoded the genomes of the living greater bilby (Macrotis lagotis) and the extinct lesser bilby (Macrotis leucura).
The greater bilby (Macrotis lagotis), 1988. Image credit: Queensland Government / CC BY 4.0.
Bilbies are unique marsupials and are the only members of the family Thylacomyidae. They include the living greater bilby and the extinct lesser bilby.
These animals are culturally important to Indigenous Australians, with their common name derived from the Yuwaalaraay word, Bilba.
Bilbies were once an important meat source for desert people, and their valuable long black tails with white fluffy ends were used in cultural practices associated with their deep symbolism in love and marriage.
Indigenous knowledge, bilby songlines, ceremonies and stories exist across Australia, linking sites and people. Their strong connection to the species continues even in areas where bilbies are now locally extinct.
Loss of this Indigenous knowledge and land management practices due to the species’ decline is a recognized threat to the persistence of bilbies in the landscape.
Historically, the greater bilby was wide ranging, distributed across both arid and temperate regions, while the lesser bilby was restricted to the sandy deserts.
The declines of both bilby species are attributed to the introduction of feral pests into Australia by European settlers, particularly predation by cats and foxes, competition from European rabbits, as well as changes to cultural fire regimes.
Sadly, the lesser bilby is now extinct, last reported alive in 1931, although it may have survived in some desert areas until the 1960s and was well known to the Indigenous peoples of the central deserts.
“The greater bilby reference genome is one of the highest quality marsupial genomes to date, presented as nine pieces, representing each of the bilby chromosomes,” said University of Sydney’s Professor Carolyn Hogg.
“It offers insights into biology, evolution and population management.”
Professor Hogg and colleagues sequenced the genome of the greater bilby using DNA from a zoo animal.
They also created the first genome for the extinct lesser bilby from the skull of a specimen collected in 1898.
“It helps us understand what gives bilbies their unique sense of smell and how they survive in the desert without drinking water,” Professor Hogg said.
“Importantly, the genome is being used to manage the bilby metapopulation in zoos, fenced sanctuaries and islands.”
“By selecting individuals for translocation and release we maximize their genetic diversity, thus improving the population’s ability to adapt to a changing world.”
The authors also used the bilby genomes to develop a more precise scat testing method to complement existing traditional land-use practices by Indigenous rangers.
“We know a lot about bilbies — where they live, what they eat, and how to track them,” said Scott West, a ranger from the Kiwirrkurra Indigenous Protected Area in Western Australia.
“It’s good to use iPads for mapping, and cameras to monitor them.”
“The DNA work also helps check if bilbies are related, where they are from and how far they traveled.”
“Using old-ways and new-ways together helps us get good information about bilbies and how to look after them. This is what two-way science is.”
The results were published in the journal Nature Ecology & Evolution.
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C.J. Hogg et al. Extant and extinct bilby genomes combined with Indigenous knowledge improve conservation of a unique Australian marsupial. Nat Ecol Evol, published online July 1, 2024; doi: 10.1038/s41559-024-02436-2
Source : Breaking Science News