Museum collections redraw the bandicoot family tree
· BehindLines newsroom
Two additional bandicoot species are emerging from museum collections. In an explanatory article published on November 2, researchers behind a study of the genus Isoodon describe how historical and modern specimens helped them revise the classification of these small marsupials from Australia and New Guinea. Their scientific study, published in the Australian Journal of Taxonomy, now recognizes seven species in the genus, compared with five previously.
The team combined morphological measurements, including skull measurements, with DNA analyses. It examined the available reference specimens and sampled populations across their historical and present ranges. The genetic data cover thousands of nuclear gene regions, obtained through the Oz Mammal Genomics initiative. This combination allows the animals’ appearance to be compared with their genetic relationships, rather than relying on a single type of evidence.
The revision recognizes the little brown bandicoot, Isoodon microtis, which the authors estimate may have disappeared around a century ago. Museum collections therefore preserved traces of a species that was not distinguished in the previous classification. The New Guinea brown bandicoot, Isoodon moresbyensis, is now recognized as a species in its own right; it was previously considered a subspecies of the northern brown bandicoot, Isoodon macrourus.
The work also changes the map for the quenda, Isoodon fusciventer. Long associated with Western Australia, it also lived around Adelaide, on Kangaroo Island and in the Nuyts Archipelago, according to the researchers’ analysis. Its recognized historical range therefore extends eastward. Conversely, the recognized range of the southern brown bandicoot becomes smaller. Several new subspecies are also described.
These changes may have consequences for conservation. The study stresses that plans to move animals between populations should take account of their revised taxonomic boundaries. A wider historical range does not mean that all present populations are doing well. The researchers note, in particular, that quenda populations in South Australia remain small and need protection. Museum collections thus help clarify which populations should be protected and help avoid confusing distinct evolutionary histories.