An international collaboration of primatologists has gleaned evidence from decades of observations of orangutans that the apes show behaviors that are culturally based.
The scientists findings push back the origins of culturally transmitted behavior to 14 million years ago, when orangutans first evolved from their more primitive primate ancestors. Previous evidence for cultural transmission in chimpanzees suggested an origin of cultural traits 7 million years ago.
The researchers also warn that illegal logging and other habitat destruction in the forests of Sumatra and Borneo could not only threaten further research into the earliest origins of culture, but continue the dangerous decline in orangutan populations.
According to first author Carel van Schaik of Duke University, the impetus to look for cultural transmission among orangutans arose from earlier findings that orangutans use tools. In particular, van Schaik and his colleagues had discovered that groups of orangutans in Sumatra use sticks to pry out fat-rich seeds from a fruit called neesia, thereby avoiding the stinging hairs that surround the seeds.
Significantly, such tool use was present only among some groups, even when the habitat appeared to be the same, the researchers found. For instance, they found that while orangutans on one side of a barrier river used tools on the fruit, those on the other did not. Nevertheless, said van Schaik, a professor of biological anthropology and anatomy, the popular perception of orangutans did not suggest that they would show cultural transmission.
"Culture requires more than just a mother-infant bond, but also extensive social contact, and orangutans are at the low end of the sociability spectrum," said van Schaik. To explore the possibility of culture in orangutans, The Leakey Foundation sponsored in February 2002 a gathering of orangutan researchers from throughout the world to correlate their data.
Besides van Schaik, co-authors included Marc Ancrenaz of the Kinabatangan Orangutan Conservation Project, Gwendolyn Borgen of Duke, Birute Galdikas of Simon Fraser University and Orangutan Foundation International, Cheryl Knott of Harvard University, Ian Singleton of the Sumatran Orangutan conservation Programme, Akira Suzuki of Kyoto University, Sri Suci Utami of Universitas International in Jararta, Indonesia, and Michelle Merrill of Duke.
"It was an open-ended exercise, in which we looked at each others videos and other data from our own observation sites," said van Schaik. "We looked for behaviors that were different among the different groups.
"While we were by no means certain that we would come up with any evidence for cultural variability, we ultimately identified 24 behaviors that likely represent cultural variants. Frankly, we were all rather giddy at the end, when we realized what had come out of our data."
According to van Schaik, the researchers are acutely aware that such differences might be nothing more than the animals adaptation to varying habitats, without social transmission.
"However, we saw that habitat did not have a significant impact on similarity of these behaviors," said van Schaik. "And our confidence that we were seeing cultural transmission was increased by analyses showing that proximate sites showed more behavioral similarity than distant sites. This finding strongly suggested that we were observing a process of innovation and cultural diffusion. "Also, we found the biggest behavioral repertoires within sites that showed the most social contact, thus giving the animals the greatest opportunity to learn from one another," he said. According to van Schaik, the discovery of cultural transmission in orangutans has implications for understanding the process in humans.
"First of all, this finding emphasizes that human culture didnt just arise de novo, but reaches far back in evolutionary time," he said. "The findings in chimpanzees meant that culture originated at least seven million years ago, and the discovery in orangutans pushes its origins back to about 14 million years.
"All these findings suggest that the first ancestral man-apes must have had a pretty solid evolutionary cultural foundation on which to build," said van Schaik.
Van Schaik and his colleagues distinguish four kinds of culture -- labels, signals, skills and symbols -- of which the Great Apes have shown the first three. Human culture is distinguished by far more sophisticated development of all four, he said. However, observations of chimpanzees and orangutans have revealed hints of symbol use, and further study might reveal clearer evidence of symbols, said van Schaik.
Van Schaik warned that political unrest and destruction of orangutan habitat could prevent such studies. "Some people have asked us Havent you learned enough by studying these animals for some 30 years?" said van Schaik. "And it is obvious from these findings that we havent. Some of the areas included in this study have already been lost to illegal logging. And even if somehow you could restore the forest and the animals, just as with human cultures, once a culture is gone, its gone."
Dennis Meredith | EurekAlert!
Biologists unravel another mystery of what makes DNA go 'loopy'
16.03.2018 | Emory Health Sciences
Scientists map the portal to the cell's nucleus
16.03.2018 | Rockefeller University
Animal photoreceptors capture light with photopigments. Researchers from the University of Göttingen have now discovered that these photopigments fulfill an...
On 15 March, the AWI research aeroplane Polar 5 will depart for Greenland. Concentrating on the furthest northeast region of the island, an international team...
The world’s second-largest ice shelf was the destination for a Polarstern expedition that ended in Punta Arenas, Chile on 14th March 2018. Oceanographers from...
At the 2018 ILA Berlin Air Show from April 25–29, the Fraunhofer Institute for Laser Technology ILT is showcasing extreme high-speed Laser Material Deposition (EHLA): A video documents how for metal components that are highly loaded, EHLA has already proved itself as an alternative to hard chrome plating, which is now allowed only under special conditions.
When the EU restricted the use of hexavalent chromium compounds to special applications requiring authorization, the move prompted a rethink in the surface...
At the ILA Berlin, hall 4, booth 202, Fraunhofer FHR will present two radar sensors for navigation support of drones. The sensors are valuable components in the implementation of autonomous flying drones: they function as obstacle detectors to prevent collisions. Radar sensors also operate reliably in restricted visibility, e.g. in foggy or dusty conditions. Due to their ability to measure distances with high precision, the radar sensors can also be used as altimeters when other sources of information such as barometers or GPS are not available or cannot operate optimally.
Drones play an increasingly important role in the area of logistics and services. Well-known logistic companies place great hope in these compact, aerial...
16.03.2018 | Event News
13.03.2018 | Event News
08.03.2018 | Event News
16.03.2018 | Earth Sciences
16.03.2018 | Physics and Astronomy
16.03.2018 | Life Sciences