by Julie Capuano for Science Recorder
Anthropologists at the University of Zurich believe that deforestation isn’t the only reason that Sumatran orangutans face extinction, according to a university report. Anthropologists say that a change in strategy is also needed to save the apes from extinction. Citing a recent population decline, anthropologists have taken a look at the genetic makeup and the migration behavior of the Sumatran orangutans to determine what can be done to preserve the animals.
Orangutans primarily live in the trees. The Sumatran orangutan, the focus of this study, is listed on the Red List of endangered species and is threatened with extinction, as approximately 6,600 of the great apes are thought to exist on the northern tip of Sumatra Island.
One of the biggest threats to the Sumatran orangutan is deforestation in Sumatra due to the need to make palm oil plantations. Anthropologists say the forests are now a fraction of their original size, and many are isolated from each other by great tracts of deforested land. They contend that this isolation could lead to inbreeding and genetic impoverishment among the Sumatran orangutans and, ultimately, this situation could lead to the extinction of these small, isolated populations.
Anthropologists say that the Sumatran orangutans are divided into several sub-populations, which are the result of natural barriers such as river and mountain ranges. However, anthropologists found that young male orangutans adapt to this geographic isolation by traveling long distances to settle down far from their birthplaces. The discovery of several orangutans who were born in one region, but whose fathers have a genetic profile that is from a different part of the island led anthropologists to this conclusion.
“So they kill two birds with one stone,” said author Alexander Nater in a statement. “On the one hand, they have conflict with the local dominant males, thereby increasing their chances of reproducing successfully, at the same time they reduce the risk of mating with closely related females from their place of birth.”
Anthropologists say that the male orangutan’s natural tendency to travel long distances ensures that inbreeding and genetic impoverishment are kept to a minimum. Their desire to travel, anthropologists argue, is a natural defense against deforestation.
“The animals of one of the studied areas of the West Coast show a very high degree of genetic diversity,” said Mr. Nater. ”This genetic diversity is a clearer indicator of a historically large population. However, since in this area is currently only around 400 orangutans live, must be assumed that the population has decreased dramatically recently.”
The authors of the study looked at fecal and hair samples to determine the genetic makeup of Sumatran orangutans.
Anthropologists say that orangutans can be adequately protected by implementing a change in strategy. Anthropologists argue that the focus of conservation campaigns should shift from the peat swamp forests on the northwest coast of Sumatra to the mountainous inland regions in North Sumatra.
“These mountain forests contain no viable orangutan populations, we must not underestimate the value of protecting this type of habitat … to maintain the genetic diversity. The strategy for the conservation of Sumatran orangutans in these mountainous areas should therefore play an important role,” said co-author Carel van Schaik in a statement.
The findings were recently published in the Journal of Heredity.
This article and photo originally appeared in and is courtesy of Science Recorder.