The Sumatran rhinoceros are considered as one of the most endangered mammals on Earth. A group of scientists recently decoded the genome of the Sumatran rhinoceros and found out that the rhino’s started facing problems during the last Ice Age. During that particular period, their habitat started to shrink rapidly, and with the increasing human interventions, their numbers started to dwindle further. Currently, there are less than 250 rhino individuals left in the world, making it one of the most threatened mammals on Earth.
The scientists became worried about this dwindling rhino population and decided to look deeper into the demographic history of the endangered mammal to figure out what caused their population to shrink rapidly and how the current population can be saved. AS per the scientist, the Sumatran rhinoceros had a huge population during the Pleistocene period about 900,000 years ago. During that period, the continental mammals invaded into the Sundaland a biological region of southeastern Asia and hence the Sumatran rhinos.
Lead researcher Herman Mays, Jr., of Marshall University said, Our genome sequence data revealed that the Pleistocene was a roller-coaster ride for Sumatran rhinoceros populations. But about 12,000 years ago, when the Pleistocene age was coming to an end, many large mammals along with the Sumatran rhinos suffered and their population shrunk. So, this indicates, that rhinos had already a suffering population since along time ago and human pressure had only increased the risk threat to their survival. This species has been well on its way to extinction for a very long time,” informed co-author, Terri Roth at the Center for Conservation and Research of Endangered Wildlife at the Cincinnati Zoo and Botanical Garden.
During the last stages of the Ice age, the glaciers started to melt, and the rising sea-levels submerged the Sundaland corridor. The land bridges connecting the islands of Java, Borneo, and Sumatra to the Malay peninsula and mainland Asia disappeared from the globe. As a result, the habitat of the Sumatran rhinos might have become dismantled, and hence, their population would have shrunk. After that, the population would have dwindled further due to habitat loss and hunting by humans. Mays said that the population got bottomed and never showed signs of recovery.
All those findings of the Sumatran rhinoceros were possible with the help of PSMC (Pairwise Sequential Markovian Coalescent). This unique approach helped the scientists to elaborate on the population history of species from the genome sequence of a single individual. The genome that they sequenced and analyzed was from a well known male Sumatran rhino kept at Cincinnati Zoo. From a single genome, scientists successfully figured out how past climate change has affected the population size of the Sumatran rhinoceros