Tasmanian tiger joey 3D scans may unlock evolutionary mystery

CT scans of thylacine specimens are being used to investigate why they resembled dogs despite last sharing an ancestor 160m years ago

Calla Wahlquist

Wed 21 Feb 2018 00.54 GMTLast modified on Wed 21 Feb 2018 01.28 GMT

Joeys of thylacines, or Tasmanian tigers, look much like the young of every other marsupial: bald, pink, and with pronounced forelimbs and jaws for crawling into their mother’s pouch and latching on to a teat.

So it’s perhaps not surprising that, in the 200-year history of collecting and cataloguing various thylacine specimens for museum exhibits, there has been a bit of a mix-up.

The issue was discovered when researchers from Melbourne University and Museums Victoria used the international thylacine specimens database, a catalogue of everything from pelts to bone fragments, to request access to every known preserved joey that had not developed past the stage of leaving the pouch, which happens around 12 weeks of age.

There were 13 on the list, including one in the Czech Republic. But two specimens, sent from the Tasmanian Museum and Art Gallery, turned out to be either quolls or Tasmanian devils.

“The one that we scanned had a different number of vertebrae to the Tasmanian tiger, and also had enlarged epipubic bones, which are the centralised bones in the pelvic area that help support the pouch,” Christy Hipsley from Museums Victoria said. “Those are very reduced in the thylacine so we can see automatically that this is definitely not a thylacine skeleton.”

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