A team of researchers in Japan say their experiments have shown that Japanese monkeys are capable of cooperating with each other to obtain food.
Researchers at Osaka University's Graduate School of Human Sciences say cooperative food gathering behavior in Japanese monkeys had been considered unlikely because of the strict hierarchy in their societies. They say monkeys of higher rank usually attack lower-ranked members of the group to dominate food.
The researchers say cooperative behavior was confirmed in a group of monkeys on Awaji Island in Hyogo Prefecture. The monkeys here are known to form a relatively tolerant group compared to others.
The researchers used a device that requires two monkeys to pull two ends of one rope at the same time to retrieve food. They say they carried out the experiment 1,500 times, and the monkeys were successful three out of five times.
They also carried out the same experiment in a less tolerant group of Japanese monkeys in Maniwa city in Okayama Prefecture. They say they experimented 200 times and the success rate was just one percent.
The researchers say it is probably the first time such behavior has been observed in over 70 years of research on the monkeys.
One says they were surprised by the findings and want to find out why monkeys in Awaji are capable of cooperation.