The Tasmanian tiger's skull fits a high-impact snap at bandicoot-sized prey
The Tasmanian tiger, extinct since 1936, was long treated as a dog-like hunter. Vera Weisbecker's group measured a head large for the body, a snout that flares at the canines, and large infraorbital foramina, a mix that fits a fast snap at rabbit-sized bandicoots. Joshua L. Gaschk's comparison of archival film across 48 predators grouped the same animal with opportunistic pouncers. The authors caution that a walking gait is a weak hunting signal, and that cranial function may not be inferable from living mammals.
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The skull carries a bite mix wolves and foxes do not share
Vera Weisbecker's group at Flinders University took geometric and linear morphometric measurements of the thylacine skull. The work found a head disproportionately large for its body, a tall and slender snout that flares at the canines, and unusually large infraorbital foramina. That combination is absent from wolves, foxes and other living mammalian carnivores, and instead approaches the mix seen in predators that take prey with a fast, high-impact snap. The authors write that this style suits rabbit-sized bandicoots rather than the livestock the animal was exterminated over. Extinct since 1936, the species had served for decades as a textbook case of convergent evolution with dogs despite roughly 160 million years of separate ancestry.[2]
Its walk falls with ambush pouncers in a 48-species comparison
Joshua L. Gaschk, with colleagues at Yale University and the University of Tasmania, compared posture, movement and locomotion across 48 living and extinct predatory mammals. Archival footage of the thylacine was read with modern biomechanical analysis, and tracking anatomical markers through each stride let the team compare motion in space and in time. The extinct Tasmanian tiger grouped with opportunistic pouncers; it did not fall in with pursuit hunters or grapplers. The comparison is published in BMC Ecology and Evolution.[1]
Walk and form remain weak guides to a hunt that was never filmed at speed
Gaschk and colleagues are careful about what a walk can show: walking pattern turned out to be shaped more strongly by evolutionary history than by hunting style, which makes it a weaker behavioural signal than the faster gaits that actually matter in a hunt. The thylacine cannot be filmed running, so the inference rests on the slow gaits that archival film captured. Weisbecker's group is equally careful moving from form to behaviour: thylacine cranial function may not be inferable from watching living mammals, and genomic work is the way they point to for a test. The reputation as a livestock predator took hold with little evidence behind it, and British colonisers wiped out the species within 130 years. Andrew Pask, Axel Newton and Douglass Rovinsky are among the co-authors.[1], [2]
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