An international scientific team of researchers from US, Britain and Tanzania found evidence that claims that chimpanzees' characteristics have been stable over long periods of time. They stated in their study, which was published in the journal "Scientific Data," the history of the sequence of their tests and their results.
Part of the team was Jean Goodall, who is among the world's most famous researcher in this field and have been working for nearly half a century studying chimpanzees in the natural habitat of the National Park in Gombe, Tanzania.
Some researchers have in the past examined thoroughly the chimpanzees and their characteristics in the region, but some scientists in the world have avoided such studies and considered them unscientific. However, researcher Goodall was the first to assume the existence of a unique personality of the chimpanzees.
Her international team conducted tests to classify each chimpanzee's behavior and personality by assessing degree of aggression and other traits. The research led to the conclusion that chimpanzees have personality characteristics.
After analyzing the archives of studies on chimpanzees at the end of the 1970s, researchers conducted almost identical tests to verify the continuity of personality characteristics of the same individuals. Other tests were conducted on other chimpanzees living in wildlife sites.
The researchers compared their findings with previous historical ones and found a remarkable continuation of the same personality characteristics of chimpanzees that are under the study.
Although they noted slight changes in the age and "wisdom" of these individuals, they observed that chimpanzee traits remained the same, as with human personality and characteristics.