Eighty-eight years ago, the last known Tasmanian tiger perished, a stark reminder of humanity’s impact on biodiversity. Recent research has shed light on the thylacine’s ancient origins, revealing a lineage of powerful marsupial predators with bone-crushing jaws. These findings offer a fascinating glimpse into the evolutionary history of this iconic, extinct animal.
A study published in the Journal of Vertebrate Paleontology details the discovery of several thylacine ancestors from the late Oligocene epoch, approximately 24 million years ago. These marsupials, unearthed in Australia’s Riversleigh World Heritage Area, predate the familiar Tasmanian tiger, scientifically known as the thylacine. The thylacine, resembling a dog with distinctive black stripes, was the largest carnivorous marsupial of its time, known for its wide jaw gape and diet of smaller marsupials and rodents. Tragically, habitat loss and overhunting, fueled by a government bounty, led to its extinction in the 20th century.
Ancient Thylacine Ancestors: A Diverse Group
The newly identified ancestors, smaller than the modern thylacine, showcase a remarkable diversity in dental adaptations. This suggests they occupied distinct carnivorous niches in the late Oligocene ecosystem. The research team, led by Timothy Churchill of the University of New South Wales, named the three new species Badjcinus timfaulkneri, Nimbacinus peterbridgei, and Ngamalacinus nigelmarveni.
B. timfaulkneri, the oldest known thylacine to date, was also the largest of the three, weighing an estimated 15 to 24 pounds. N. peterbridgei exhibits characteristics that place it closer to the Tasmanian tiger than the other discovered ancestors, suggesting it may represent the oldest known direct ancestor of the extinct carnivore.
Challenging Old Assumptions about Australian Megafauna
These findings challenge the previous notion that reptiles dominated Australia’s predator landscape during this period. The growing fossil record of marsupial carnivores, including these new thylacinids, paints a more complex picture of the ancient ecosystem. According to paleontologist Michael Archer, a co-author of the study, all but one of these thylacine lineages went extinct around 8 million years ago, leaving only the line that eventually led to the modern Tasmanian tiger.
The Tasmanian tiger disappeared from mainland Australia no later than 2,000 years ago, persisting only on the island of Tasmania until its final demise in a zoo in 1936. However, some researchers believe the species may have survived in the wild until the 1960s.
The Possibility of De-Extinction
The thylacine has recently garnered renewed attention due to efforts in de-extinction. A biosciences company is working to resurrect a proxy thylacine – an animal genetically engineered to fill the ecological role of the extinct marsupial. While de-extinction remains a complex and challenging endeavor, the successful recovery of RNA from a thylacine specimen last year marks a significant step forward. This achievement represents the first time RNA has been retrieved from an extinct species.
While the future of de-extinction remains uncertain, the discovery of these ancient thylacine ancestors provides valuable insights into the rich evolutionary history of this remarkable marsupial and its place in Australia’s prehistoric ecosystem. These findings underscore the importance of continued paleontological research in unveiling the secrets of the past and informing conservation efforts in the present.
