Mother and child
A mother and baby chimpanzee relax in a tree in the Goualougo Triangle, an area of lush forest in the Republic of Congo that is now within the protected borders of the country's Nouabalé-Ndoki National Park.
Though the 100-square-mile (260-square-kilometer) region is home to forest elephants and western lowland gorillas, it is perhaps best known for its population of "naïve" chimpanzees apes so isolated from human contact that they are known to boldly approach researchers to investigate the foreign visitors.
"Rather than flee at the sight of humans, which is typical in areas where the apes have been hunted, the chimpanzees in the Goualougo Triangle would approach us and move closer to get a better look at their bipedal cousins," said Crickette Sanz, a lead ape researcher with the Goualougo Triangle Ape Project, and an assistant professor at Washington University.
Scientists discovered that the chimpanzees also possessed unique tool-using skills. They not only "fished" for termites with long twigs, as other chimpanzees do, sticking thin sticks into termite mounds to retrieve the insects, but also used shorter twigs and branches to poke holes in the mounds first.