Similar to humans, male orangutans prepare their travel itinerary beforehand and also share them with others members of the community a day in advance, according to a new study conducted by anthropologists at the University of Zurich.
"Our study makes it clear that wild orangutans do not simply live in the here and now, but can imagine a future and even announce their plans," said primatologist Carel van Schaeik of the University of Zurich, who led the study. "In this sense, then, they have become a bit more like us."
The findings are published in the PLoS ONE. Frans de Waal of Atlanta's Emory University, who was not a part of the study, said that scientists had earlier observed similar behavior in zoos and controlled experiments but this is the first study that provides an evidence of travel planning in the wild.
Van Schaeik and his team arrived at the conclusion after following nearly 15 wild male orangutans across the Sumatran rain forests for up to 10 days each. They observed their verbal communication, body language and travel patterns. They followed the orangutan communities for about 10 to 12.5 hours each day.
Among the monkeys, adult males frequently venture into the forest alone. Males would face in the direction of their planned route and release a long whooping call, as long as four minutes.
"We found that males emitted long calls mostly facing the direction they traveled a few hours later, or even after a night's rest," study co-author Karin Isler said.
They share their plans so that females could come along or remain in close proximity to their favored mates. These males protect the females from being assaulted by other male orangutans.
"To optimize the effect of these calls, it thus would make sense for the male to call in the direction of his future whereabouts, if he already knew about them," van Schaik said. "We then actually observed that the males traveled for several hours in approximately the same direction as they had called."
The researchers also found that the males announced changes in travel direction with a new long call. More research is required to completely find out how orangutans communicate.
