Primatology.net

Tool use among orangutans was first documented by Carel van Schaik. In 1994, Carel observed orangutans developing tools to help themselves eat, while conducting field work in Gunung Leuser National Park, in the northwest Sumatra.

Specifically the orangutans were using sticks to pry open pulpy fruits that have “Plexiglas needles” capable of delivering a painful jab covering them. Using the tools, the orangutans were getting past handling the prickly husk and into the nutritious fruit. From an anthropological viewpoint, tool use represents an aspect of culture, since the entire group participates in a behavior that has developed over time. One unique thing to clarify is that only Sumatran orangutans have been observed to use tools, not orangutans from Borneo.

Recently, Gerd Schuster co-author of Thinkers of the Jungle: The Orangutan Report, took this photograph of,

“a male orangutan, clinging precariously to overhanging branches, flails the water with a pole, trying desperately to spear a passing fish…

The extraordinary image, a world exclusive, was taken in Borneo on the island of Kaja…

This individual had seen locals fishing with spears on the Gohong River.

Although the method required too much skill for him to master, he was later able to improvise by using the pole to catch fish already trapped in the locals’ fishing lines.”

Pretty awesome image, no? If you wanna read more about orangutan tool use, here are three papers on the topic:

Schaik, C.P., Fox, E.A., Sitompul, A.F. (1996). Manufacture and use of tools in wild Sumatran orangutans. Naturwissenschaften, 83(4), 186-188. DOI: 10.1007/BF01143062

Call, J., Tomasello, M. (1994). The social learning of tool use by orangutans (Pongo pygmaeus). Human Evolution, 9(4), 297-313. DOI: 10.1007/BF02435516

van Schaik, C.P. (2003). Orangutan Cultures and the Evolution of Material Culture. Science, 299(5603), 102-105. DOI: 10.1126/science.1078004

It has been far too long since I’ve updated this blog. I apologize, there certainly has not been a lack of material to share — just a lack of time and overemphasis on Anthropology.net, which is totally my bad, I don’t intend to neglect this site again.

Anyways, photographer Frans Lanting recently travelled to take photos of the Fongoli chimpanzees in Senegal. He was on NPR yesterday to share his experiences. The Fongoli chimps, if you don’t remember, are the ones that have been observed to hunt with spears. Jill Pruetz actually was the one to see this behavior and I covered this news last year. I was a bit skeptical, but it seems like Lanting and Pruetz were able to observe this behavior again. From the NPR article,

Lanting and Pruetz observed the primates fashioning spears from tree limbs to capture bush babies, small mammals that hide deep inside hollow trees.

“No one has ever seen that before in any other chimps elsewhere,” Lanting says.

The Fongoli chimps often displayed behaviors akin to those of early humans.

“There is very little fundamental difference in my opinion between how these chimps live and how our very earliest ancestors lived,” Lanting says. “It’s just like looking at human beings. I regard these chimpanzees as very shy, private people.”

Like humans, the male chimps also seem to have a bit of a rhythmic bent; Lanting observed them drumming on hollow baobab trees as a way of impressing potential mates and intimidating rivals.

It took several months for the Fongoli chimps to begin accepting Pruetz and Lanting, who says they wore the same clothes every day so that the animals could become accustomed to their presence.

On days that the chimps let their guard down, Lanting says, he and Pruetz were able to observe behaviors that “are all confirmation to the fact that the boundaries between humans and chimps are really quite fuzzy.”

Be sure to check out the 9 minute long audio interview with Lanting.