In 1960, Jane Goodall saw two chimps remove the leaves off of small twigs and used them as tools to fish for termites in the ground, which they ate.
It was the first time a scientist observed chimpanzees turning an object into a tool and using it for a specific purpose. But it was unclear how the chimps learned to do this. More than 50 years later, scientists have for the first time captured videos of chimpanzee mothers teaching their offspring to fish for termites.
The footage, taken in the Republic of Congo by researchers from the Goualougo Triangle Ape Project and Washington University in St. Louis, show several examples of mother chimpanzees handing termite fishing tools to their young.
Sometimes the mother handed the offspring her tool and scavenged for another. At other times, the mother would split it in half and give away one of the pieces so that they could still forage for termites.
"It's been challenging to document teaching before," said Stephanie Musgrave, a Ph.D. student at Washington University and the lead author of the study. "Chimps are excellent observers and other means of learning might suffice for them to acquire skills, but there's been some suggestion that perhaps of these more complex tool tasks, that more active facilitation on the part of the mother might be more helpful for helping their offspring learn."
In other words, scientists thought that young chimps may have learned how to fish for termites, as well as other skills, by watching the adults. But recent technology has allowed researchers to observe chimps for longer stretches of time. Washington University had pioneered the use of remote cameras for observing wild chimpanzees in Congo, which allows scientists to study the animals and their habitat without having to make them accustomed to humans and potentially exposing them to diseases.
"It's only been recently that chimpanzees in Central Africa have been able to be directly and repeatedly observed over time," Musgrave said. "We're really still at the tip of the iceberg in beginning to understand how these particular tool traditions are passed on."
Humans share about 99 percent of their DNA with chimpanzees, so observing their behaviors can provide profound insight into how humans have evolved and what exactly makes us unique.
"Observing and studying great apes is a tremendous privilege and I love doing this research," Musgrave said. "I think it's of interest to many people because it helps us understand the behavior of our closest living relatives in the animal kingdom. [It] might tell us something about how we're similar to and different in terms of our cultural behaviors and technology."
The research appears in the journal Scientific Reports.
Videos of the chimpanzees can be seen here.
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