Tool-Using Orangutans a Clue to the Past

A Duke University researcher’s discovery that wild orangutans can make and use tools to gather food could shake some fundamental ideas about human origins, including when and how intelligence evolved.

Duke anthropologist Carel van Schaik found the 12 tool-using orangutans in a virtually unexplored region on the island of Sumatra. Van Schaik presented the finding recently at a Duke seminar.

“They’ve seen it at last. Bully for the orangs,” said Jane Goodall, the British primatologist who discovered tool use in chimpanzees in the early 1960s. Goodall said she long suspected orangutans and all great apes could use tools.

Van Schaik’s finding suggests that the ability to use tools intelligently was present in human ancestors 13 million to 16 million years ago, before orangutans split from the line. It challenges the conventional wisdom that tool use was a much more recent development and was a central factor in the rapid evolution of humans from apes.

“We’ve always had a tendency to look at human evolution as something fundamentally different than other animals,” Van Schaik said. “This adds one more nail to that coffin. It means that all unique human features did not arise fully fledged and suddenly. You can see them gradually appear over time.”

Orangutans have long been a puzzle for scientists who study them. They use tools very creatively in captivity but rarely do so in the wild.

“To me, tool use proves more strongly that we’re dealing with sentient, intelligent, conscious individuals that are very close to being human,” Van Schaik said.