Chimpanzees stand alongside gorillas as Africa’s only great apes and are the closest living relatives of humans. The common chimpanzee (Pan troglodytes) is the best known of two species – the other being the bonobo, which is smaller, less aggressive and forms female, rather than male-dominated societies.
The close affinity of chimps with humans is evident in many aspects of their behaviour, from their large brains and complex social intelligence and communication skills, to their ability to fashion and use tools. It has also explained the many ways in which people have exploited them, whether as objects of circus entertainment, or subjects for laboratory experiment. Both chimpanzee species are confined to equatorial rainforest, with the common chimpanzee ranging from Cote D’Ivoire in the west, across the Congo Basin – north of the Congo river – to Uganda and Tanzania in the east. An estimated 150,000–300,000 are thought to remain in the wild.
Facts about the Common Chimpanzee
- The chimpanzee genus Pan forms part of the subfamily Homininae, which also includes humans. The lineages of chimps and humans are thought to have separated some five to twelve million years ago. The most recent molecular research concludes that the difference in DNA between humans and chimps is no more than 1 – 1.2%.
- Among a variety of tools used by chimpanzees are: sticks of different length, with which to both break into termite mounds and fish out the termites; stones of different sizes that serve as both hammer and anvil for breaking open nuts; leaves used as sponges or spoons to collect and drink water; and pointed sticks (sharpened by the apes’ teeth) with which to spear bushbabies and squirrels from small tree holes.
- Experimentation on all great apes (in practice, chimps) was banned by the European Union in 2010. It continued in the US, however, where at that time there were more than 900 chimpanzees housed in laboratories. In 2015 the US National Institute of Health (NIH) concluded that experimentation on chimpanzees was no longer required. To this day, many chimps remain in warehouses because of the difficulties involved in rehousing them.
- During the 1960s, researchers Allen and Beatrix Gardner spent 51 months teaching American Sign Language (ASL) to a chimp named Washoe. Over this time Washope learned 151 signs and spontaneously taught many of them to other chimpanzees. By the end of her life, Washoe had mastered over 800 signs.
- Research from the Tai National Park in Cote D’Ivoire has concluded that a form of prostitution exists among the chimpanzees there, in which females use sex to buy meat from males – often doing so on a long-term basis.