Sumatran rhinos are one of the most endangered animal species in the world. These plant-eating animals originate from the order Perissodactyla and can reach a shoulder height of 3.67 to 4.76 feet. It’s not hard to recognize the species. They have two skin folds which encircle the body around the legs and trunk area. Two horns are located on the snout, with the frontal horn being larger and more visible compared to the nasal one. According to a group of scientists from the U.S., the problems concerning the extinction of these mammals had started during the last Ice Age, as their habitat got smaller. After that, it was human impact that affected the number of living rhinos, now counting fewer than 250 left in the wilderness. They conducted a study which was published in the journal Current Biology
“Our genome sequence data revealed that the Pleistocene was a roller-coaster ride for Sumatran rhinoceros populations,” said Herman Mays, Kr., from Marshall University in the press release.
“This species has been well on its way to extinction for a very long time” Terri Roth of the Center for Conservation and Research of Endangered Wildlife at the Cincinnati Zoo and Botanical Garden, added.
The Pleistocene is the time in terms of geology, a period between 2,588,000 to 11,700 years ago, during the latest Ice Age. The researchers have been sequencing and analyzing the first whole genome which belongs to the well-known Sumatran rhino male, Ipuh, located at the Cincinnati Zoo.
Ipuh had been at the zoo since the 1990s, but unfortunately, his life ended four years ago when he was 33. Ipuh provided three offspring, which is more than compared to other Sumatran rhinos in the world. His genetic material has been moved into a gene bank. Scientists used Ipuh’s DNA to get the population history of Sumatran rhinos. According to the scientists, the population of this species numbered almost 60,000 individuals roughly 950,000 years ago. However, around 12,000 years ago marked the end of the Pleistocene time, which means that rhinos lost a great part of their natural habitat, similar to other large mammals. Due to climate changes, by 9,000 years ago the number of individuals continued dropping, and showed no signs of recovery.
“Their population bottomed out and never showed signs of recovery,” Professor Mays said. “The Sumatran rhinoceros species is hanging on by a thread,” Dr. Roth said. “We need to do more to save it.”
The Sumatran rhinos once lived on the foothills of the Himalayas in Bhutan and north-eastern India, even through southern China, Myanmar, Thailand, Cambodia, Laos, Vietnam, and the Malay Peninsula. The animal also roamed the islands of Sumatra and Borneo in Indonesia. The species now mainly live in Sumatra and are considered Critically Endangered by the International Union for the Conservation of Nature (IUCN).
Right now, there are over 20 Sumatran rhinos that are kept in captivity, mainly located in Indonesia and Malaysia, while a few of them are located in the U.S.