Chimpanzees drum with regular rhythm when they beat on tree trunks, a new study shows.
last shared a common ancestor around 6 million years ago. Scientists suspect this ancient ancestor must have been a drummer 鈥 using beats to communicate.
鈥淥ur ability to produce rhythm 鈥 and to use it in our social worlds 鈥 that seems to be something that predates humans being human,鈥 said study co-author Cat Hobaiter, a University of St Andrews primatologist.
Previous research has shown that chimps have their own signature drumming style. A new analysis of 371 bouts of chimpanzee drumming demonstrates that the chimps 鈥渃learly play their instruments — the tree trunks — with regular rhythms,鈥 said University of Amsterdam music cognition researcher Henkjan Honing, who was not involved in the study.
When bounding through the jungle, chimps will often grab hold of the tall buttress roots of rainforest trees. Sometimes they pound them several times to create low-frequency sounds that can be heard for a kilometer or more through the forest.
Scientists believe that the drumming is a form of long-distance communication, perhaps to alert other chimps where one chimp is waiting or the direction it is traveling.
鈥淚t鈥檚 a way of socially checking in,鈥 said Hobaiter, adding that each chimp has its own 鈥渋ndividual signature 鈥 a pattern of beats that allows you to recognize who鈥檚 producing that drumming.鈥
The new work showed that chimps from different regions of Africa drum with distinctly different rhythms, with western chimps preferring a more even beat while eastern chimps used varied short and long intervals between beats. The research was published Friday in the journal .
It’s well-known that chimps use tools such as rocks to crack open nuts and sticks to 鈥渇ish鈥 termites from their mounds. Tree roots can also be tools, the researchers say.
Chimps are selective about which roots they pound, said co-author Catherine Crockford, a primatologist at the CNRS Institute for Cognitive Sciences in France. Certain shapes and wood varieties create sounds that travel well through dense jungle.
The drummings are likely “a very important way to make contact,” she said.
At closer distances, chimps use a repertoire of vocal calls more complex than scientists once thought, according to a separate study in
Researchers analyzed how chimps combined sounds 鈥 such as a call associated with resting and one used to invite play 鈥 to create new meanings. In this example, the combined call was an invitation to nest together nearby at night.
鈥淲e have probably underestimated the flexibility and complexity of animal communication,” said Crockford, who was part of both research teams.
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