Only four thylacine brains are documented to have survived intact. By comparing the thylacine brain structure to the Tasmanian devil, we can then infer structural-functional relationships between brain and behavior. Similar reconstructions in cetacean brains have shown this is possible in specimens more than a decade old. To answer these questions, we used MRI and diffusion-tensor imaging (DTI) to reconstruct the architecture and white-matter pathways of an intact thylacine brain. A larger, more gyrified, brain might simply reflect the larger body size of the thylacine, or it might reflect a more sophisticated cognitive architecture, perhaps related to its predatory ecology. Endocasts have suggested a more highly gyrified cortex than the Tasmanian devil, which is consistent with a greater encephalization quotient of the thylacine (0.45) than the devil (0.36). ![]() To further understand thylacine behavior and to place the thylacine in its evolutionary context, we can look to brain morphology. This is in contrast to the scavenging strategy of the extant carnivorous marsupial, the Tasmanian devil ( Sarcophilus harrisii). Analysis of skull mechanics have come to different conclusions about the size of the thylacine’s prey, with one analysis suggesting that the thylacine preyed on animals smaller than its size while another suggested the opposite. Analysis of tooth morphology suggested the thylacine was a “pounce-pursuit” predator that killed prey in the 1–5 kg range. The geometry of its elbow joint suggested that it hunted more by ambush than pursuit. Įven without naturalistic data, it is still possible to reconstruct aspects of thylacine behavior from artifacts. Thus, in one of the great lost opportunities, very little is known about thylacine behavior. The only records of behavior in their natural habitat are stories passed on by farmers, hunters, and trappers. Although several animals had been kept in captivity in the early 1900s, no systematic investigation of the thylacine’s behavior was ever documented. The thylacine’s demise can be directly attributed to the bounty scheme in place from 1830–1914 that resulted in the killing of several thousand animals and indirectly to the loss of its habitat from farming activity. A carnivorous marsupial, the thylacine was the apex predator in Tasmania until the last known animal died in the Hobart Zoo in 1936. The Tasmanian tiger ( Thylacinus cynocephalus)–aka the thylacine–was, perhaps, the most iconic animal of Tasmania. Functionally, the thylacine’s brain may have had relatively more cortex devoted to planning and decision-making, which would be consistent with a predatory ecological niche versus the scavenging niche of the devil. These results are consistent with theories of brain evolution suggesting that larger brains are more modularized. Similarly, the thalamic projections had a more orderly topography in the thylacine than the devil. The basal ganglia reconstruction showed a more modularized pattern in the cortex of the thylacine, while the devil cortex was dominated by the putamen. ![]() We reconstructed the cortical projection zones of the basal ganglia and major thalamic nuclei. For functional interpretation, we compare to the white matter reconstructions of the brains of two Tasmanian devils ( Sarcophilus harrisii). Here, we show that it is possible to reconstruct white matter tracts in two thylacine brains. Any thylacine brain, however, would be more than 100 years old. Recent advances in brain imaging have made it possible to scan postmortem specimens of a wide range of animals, even more than a decade old. ![]() Because its natural behavior was never scientifically documented, we are left to infer aspects of its behavior from museum specimens and historical recollections of bushmen. Set the ABC News website or the app to " Tasmania Top Stories" from either the home page or the settings menu in the app to continue getting the same national news but with a sprinkle of more relevant state stories.The last known Tasmanian tiger ( Thylacinus cynocephalus)–aka the thylacine–died in 1936. The research was published in the journal Science of the Total Environment. "There's a remote possibility, I think, that the animal might still be there, but it's very unlikely and diminishing as we speak." He did not dispute that there was the possibility that thylacine might have existed past the 1930s. "Any sighting is prone to the possibilities of the person being right, the person being wrong, the person having some strange delusion, or the person lying."
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