This is the VOA Special English ENVIRONMENT REPORT.
Orangutans are great apes that live in coastal jungles on the islands of Borneo and Sumatra. A team of international scientists has found evidence that some orangutans have developed their own culture. They found evidence that orangutan groups have different ways to communicate, eat and use tools.
The findings suggest that the animals’ early ancestors may have created their own culture as early as fourteen-million years ago. That is when orangutans and other great apes last had a common ancestor. Earlier studies had shown that great ape culture had been in existence for up to seven-million years.
For scientists, culture is the ability to invent and learn ways of doing things. These methods must not be the direct result of biology or the environment. They are learned from others and passed on to individuals.
Science magazine published the study about orangutans. The scientists collected evidence from years of observations in six areas on Borneo and Sumatra. The scientists found that the animals demonstrated a total of twenty-four signs of cultural activity. Several actions were demonstrated in some orangutan groups, but not others.
For example, members of some groups make a kissing noise by tightening their mouths and sucking in air. Some groups use leaves to clean themselves or protect their hands from sharp objects. Yet other groups use leaves to crush insects or gather water. The scientists found that some of the animals use sticks as tools to remove insects from holes in trees. Other orangutans use sticks to remove seeds from fruit or to touch their bodies.
The study also found that some orangutan groups play a sport for fun. The animals climb up a dead tree and ride on the tree as it falls down. They hold onto another tree just before the dead tree hits the ground. Other orangutans often watch this activity.
For years, scientists thought that only humans had cultures. However, evidence for socially-learned traditions among animals is increasing. The best evidence came from a study of chimpanzees in Africa in nineteen-ninety-nine. Scientists say the growing amount of evidence about animal culture reduces the differences between humans and animals and between culture and nature.
This VOA Special English ENVIRONMENT REPORT was written by George Grow.