Swedish Scientists Recover RNA from Extinct Tasmanian Tiger for the First Time

The Tasmanian tiger, or thylacine, was a carnivorous marsupial the size of a dog that once lived on the Australian continent and its surrounding islands. The Tasmanian tiger was a top predator that hunted kangaroos and other prey. Humans are the main cause of the extinction of this species, but scientists have not given up on learning about this extinct animal. According to an Associated Press report, researchers said on Tuesday, September 19, that they have recovered RNA, or ribonucleic acid—the genetic material found in all living cells that structurally resembles DNA—from the dried skin and muscle of a Tasmanian tiger that has been preserved in a museum in Stockholm, Sweden, since 1891. In recent years, scientists have previously extracted DNA, or deoxyribonucleic acid, from ancient animals and plants, some dating back 2 million years. However, this study marks the first time RNA, which is much less stable than DNA, has been recovered from an extinct species. Although this was not the main focus of the research, the ability to extract, sequence, and analyze ancient RNA could enhance other scientists' efforts to recreate extinct species. Recovering RNA from ancient viruses could also help decipher the causes of past pandemics. The remains of the Tasmanian tiger were in a semi-mummified state at the Swedish Museum of Natural History, with skin, muscles, and bones preserved, but its internal organs had decayed. There were questions about how long RNA could survive in such conditions. Luve Dalian, a professor of evolutionary genetics at the Swedish Paleontology Center, stated, "Most researchers believe that RNA survives only for a very short time—like a few days or weeks—at room temperature. This is probably true when samples are wet or moist, but apparently does not hold when they are dry." Aside from its tiger-like stripes on its back, the Tasmanian tiger resembled a wolf more closely. The arrival of humans in Australia about 50,000 years ago led to widespread population losses of these mammals. The arrival of Europeans in Australia in the 18th century, following its colonization, worsened the situation for the remaining population of this species, which was mainly concentrated on Tasmania. The excessive hunting of this animal, which was considered a threat to livestock, was often accompanied by rewards for farmers and is believed to be the main reason for the extinction of this species. The last known Tasmanian tiger died in 1936 in the Tasmanian Zoo from disease.