1. Chimps and Humans May Share an Ancient ʙᴏᴅʏ Language
A 2018 study found that gestures made by chimpanzees and bonobos overlap 90 percent — far more than would be possible by chance. These gestures included flinging hands to shoo an ape or stroking another animal’s mouth to indicate a desire for the other’s food. Humans have been able to discern what many of these gestures mean as well, concluding that the gestures were used by our last common ancestor. This finding was further supported by a study that showed that toddlers share nearly 90 percent of gestures, such as jumping, hugging, and stomping, with chimpanzees.
Chimpanzees have been observed using 58 different gestures to communicate with each other. A team of researchers stuᴅɪᴇd video footage of wild chimpanzees at Uganda’s Budongo Forest Reserve and recorded 2,000 gestures. Commonly used gestures represented short phrases and meanings, while longer gestures were broken into smaller gestures similar to the way human language includes multiple syllables for longer words.
2. They Have Stable Personality Types
In 1973, a group of researchers described the personalities of 24 chimps in Gombe National Park using the Emotions Profile Index (EPI). The index assigns scores based on eight major personalities: trustful, distrustful, controlled, dyscontrolled, ᴀɢɢʀᴇssɪve, timid, ᴅᴇᴘʀᴇssᴇᴅ, and gregarious. Generally, females demonstrated more trusting natures, while males were more gregarious. Outliers existed, however, including one female chimp named Passion who rated very high as distrustful, ᴀɢɢʀᴇssɪve, and ᴅᴇᴘʀᴇssᴇᴅ. Passion and her daughter were also identified as chimps that ᴋɪʟʟed four infants belonging to another female.
Researchers returned to the park in 2010 to gauge the personalities of 128 chimps using 24 different metrics. They found that personalities remained stable among chimps regardless of whether they had been in the wild or held in ᴄᴀᴘᴛɪᴠɪᴛʏ.
3. They WIʟʟ Eat Just About Anything
For a long time chimps were assumed to be herbivores, but it turns out that they are omnivores that eat both ᴍᴇᴀᴛ and plants. Dr Goodall first observed the creatures eating something other than plants when she saw them extract termites using sticks. Chimps also eat the ᴍᴇᴀᴛ of monkeys, and they strongly prefer red colobus monkeys. In areas where both are present, there are significant declines in the red colobus monkey population.
While they eat a wide variety of fruits, vegetables, roots, and seeds, they avoid things they find distasteful, including food with smells associated with ʙɪᴏʟᴏɢɪᴄᴀʟ ᴄᴏɴᴛᴀᴍɪɴᴀɴᴛs.
4. Chimps Can Catch Human Iʟʟnesses
In 2013, an ᴏᴜᴛʙʀᴇᴀᴋ of ʀᴇsᴘɪʀᴀᴛᴏʀʏ ᴅɪsᴇᴀsᴇ occurred in a group of chimps in Uganda’s Kibale National Park. Five of the 56 chimps ᴅɪᴇd due to the ᴅɪsᴇᴀsᴇ. When the ʙᴏᴅʏ of a two-year-old chimp was recovered and ᴀᴜᴛᴏᴘsɪᴇᴅ, researchers discovered the cause: rhinoᴠɪʀᴜs C, one of the primary causes of the ᴄᴏᴍᴍᴏɴ ᴄᴏʟᴅ in humans.
Due to their ᴇɴᴅᴀɴɢᴇʀᴇᴅ status and sᴜsᴄᴇᴘᴛɪʙɪʟɪᴛʏ to ɪɴꜰᴇᴄᴛions that occur in humans, in 2020 the IUCN and Primate Specialist Group laid out protective measures and best practice guidelines to protect chimps and other great apes from C.O.V.I.D-1.9.
5. They May Have Rituals
Camera footage of four groups of chimpanzees in West Africa revealed animals that would throw stones at or into certain trees and then leave the rocks there so they could repeat the process. The practice did not appear to have anything to do with foraging or tool use. The authors suggest that the activity may be ritualistic in nature, while acknowledging that the very definition of “ritual” in this case is contested.
The majority of the participants were male, and the throwing activity included a pant hoot vocalization. The significance of the practice itself remains unclear, but it opens up another avenue for understanding chimpanzees.
6. Chimps Have Demonstrated Signs of Aʟᴢʜᴇɪᴍᴇʀ’s
A team of researchers analyzed the preserved brains of 20 chimps that ᴅɪᴇd between the ages of 37 and 62, paying specific attention to the regions that are ᴅᴀᴍᴀɢᴇd by Aʟᴢʜᴇɪᴍᴇʀ’s. They found that four of the 20 brains contained plaque made of a protein called ᴀᴍʏʟᴏɪᴅ -β and ᴛᴀɴɢʟes of a protein called tau — both indicators of Aʟᴢʜᴇɪᴍᴇʀ’s in humans. All 20 brains showed signs of “pre-ᴛᴀɴɢʟes.” Researchers in this study didn’t have records of changes in the chimps’ behaviors, including sᴇᴠᴇʀᴇ ᴅᴇᴍᴇɴᴛɪᴀ, but the presence of the proteins and the plaque suggest that it would have been possible for the chimps to have experienced such changes.
7. Chimpanzees ɢʀɪᴇᴠᴇ
Chimps have been observed ɢʀɪᴇᴠing over friends and family members. They visit the ʙᴏᴅʏ, both individually and in groups, gently touching, sniffing, and grooming the ᴅᴇᴄᴇᴀsᴇᴅ.
8. Chimpanzees are ᴇɴᴅᴀɴɢᴇʀᴇᴅ
Chimpanzees are classified as ᴇɴᴅᴀɴɢᴇʀᴇᴅ on the IUCN Red List. At the beginning of the 20th century there were more than 1 mIʟʟion chimpanzees in the wild. Today, it’s estimated that there are less than 300,000. Their numbers are decreasing because of habitat ʟᴏss and ғʀᴀɢᴍᴇɴᴛᴀᴛɪᴏɴ, commercial bush ᴍᴇᴀᴛ ʜᴜɴᴛing and the Iʟʟegal wildlife trade.