by Arden Robert
“Do all the primates act the same?” is one of the first questions people ask when I tell them what I do. The answer to that is simple—no.
While there may be a “template” for how the primates are expected to act, they all have different variations that make them unique. One example is the dominance display of chimps. Dominance displays occur when a male (or female) is attempting to intimidate a subordinate or to gain rank. A typical dominance display begins with the chimpanzee standing up straight with hair bristling, shoulders hunched and compressed lips so that his or her body looks larger and face meaner.
In the wild, the displaying chimpanzee will start to sway back and forth, shoving brush and other vegetation out of the way with exaggerated movements. The excited chimpanzee may also hurl large rocks, tear off tree branches and drag them while running rapidly down a hill or toward a screaming potential victim. While dominance displays don't usually erupt into full scale fighting, those chimpanzees that don't get out of the way fast enough are likely to be slapped.
All male chimps will display, but the way they do it is unique to each individual. Buck, 24, who arrived at PPI from a pet home in 2009, uses a hard hat to bang on the structures in his habitat to make noise. Deeter, 19, who was born at the sanctuary after his mom Betty, already pregnant, was released to PPI by the United States Air Force, prefers to throw toys, balls, rocks or anything he can get his hands on to show off. The females all have different ‘voices’ and pant hoots. After observing and learning these differences I can tell which chimp is making noise even without seeing them.
Another big difference between individual primates is their eating habits. Just like people, every primate has a favorite and least favorite food. Kimchi the gibbon, for example, loves agave while her enclosure mate, Jose Maria, would much rather have dried fruit snacks. Knowing an individual’s favorite food is helpful for more than creating food enrichment. By hiding medication in favorite foods, caregivers can be sure that it will be taken without hesitation.
While most of these differences are generalized there are some that are a little more quirky. When macaques are given small mirrors most will look at themselves for a few minutes but quickly lose interest. However, Bojangles, a long-tailed macaque who arrived to the sanctuary in 2011 along with 26 other male macaques from a now defunct New Jersey lab, uses his mirror to look behind him at his surroundings throughout the day. When working in my section, I can see the sun shining off the mirror and know it is just Bojangles watching me work.
Some behaviors provide a glimpse into the animals past. Chimps Effie and Laura were used in breeding programs at labs and had their babies taken away from them at a very young age. Chimps have very strong maternal instincts and care for their young for years. Having their babies taken away has had a lasting effect on them. Now they both like to carry around stuffed animal babies and are very rarely seen without them.
Getting to know each primate’s personality is one of my favorite parts of the job and every day I learn something new about them, but it’s not all just for fun. Primates are notoriously good at hiding sickness and injuries. It is important for caregivers to be able to notice even the slightest change in personality so the animals can receive the necessary medical treatment.