When traveling, it’s common to run across non-human primates—such as spider monkeys, squirrel monkeys, capuchins, and rhesus macaques— either in a wild or captive setting. In some tropical tourist destinations, locals will carry these animals, eager to hand them over for a quick picture and a few dollars. In other places, tourists have the opportunity to interact with free-range monkeys. The media is filled with funny videos of monkeys stealing sunglasses and water bottles from unsuspecting visitors. However, these funny antics can quickly turn dangerous when primates accidently bite or scratch these tourists. What people often don’t realize is that primates are highly communicative and visual animals. If one does bite or scratch, it likely has already given a warning signal that you didn’t interpret correctly1. Here’s a quick lesson on animal communication, as we break down some common misconceptions about primate facial expression in order to ensure safe non-human primate ecotourism!
This young primate isn’t smiling: he’s showing submission to deter a more dominant individual. Respect his social cue, and leave him be. [Source]In non-human primates, a “goofy” grin, often mistaken as a sign of happiness, is actually a signal of anxiety and submission. Often, when primates give this “smile”, otherwise known as a fear grimace, they’re signaling submission to a perceived dominant individual. Tourists, mistaking this a signal as a sign of friendship, will often get attacked when they back an anxious monkey into a corner. The monkey likely perceived their approach as a threat, and demonstrated species-typical primate behavior—if your aggressor doesn’t respect your sign of submission: attack.
This yawn isn’t conveying sleepiness: it’s an advertisement for those giant canines and the damage they can do! [Source]Similarly, a yawn in a social context is often used as a warning signal. This yawn demonstrates the size of a monkey’s canine teeth and shows its willingness to use said canines. Tourists assume this yawn implies sleepiness. Best advice: give this anxious primate some space. The easiest way to keep non-human primates happy and keep you safe is to keep your distance and avoid direct eye contact. Direct eye contact is a sign of dominance and is a sure way to attract unwanted attention.
An infant vervet monkey, sitting next to his highly defensive mama. [Source]When around non-human primates, it’s also easy to want to approach small individuals or infants. They’re adorable, friendly, and make for fantastic Instagram pics (#ecotourism). Generally speaking though, it’s best not to approach younger monkeys. Many monkey species, especially rhesus macaques (a common species at tourist-destinations) will aggressively defend an infant they perceive as being threatened.
A macaque with her infant in a tourist destination. [Source]There’s another reason why it’s important to respect non-human primate social cues. Beyond general respect for animals and their space, and the potential for your presence to stress them out, direct contact with primates can have detrimental health effects for both you and the animals. Because non-human primates are so closely related to humans genetically and evolutionarily, diseases can easily pass between us. By putting yourself close to wild primates, you put both yourself and the animals at risk of contracting diseases. This can be something as small as a cold, or as fatal as Ebola2 or Herpes B3.
Believe me, the temptation to interact with wild primates is intense! As a primatologist, it’s a huge honor to be able to interact with the primates that have driven my career. So, if you do choose to interact with non-human primates, do so at your discretion and make sure you’re equipped with the right knowledge to respect a primate’s behavior. As with marine ecotourism, do your research. Sanctuaries and wildlife rescues with good reputations are the best places to observe and appreciate non-human primates in a safe setting.
2Bermejo, M., Rodríguez-Teijeiro, J. D., Illera, G., Barroso, A., Vilà, C., & Walsh, P. D. (2006). Ebola outbreak killed 5000 gorillas. Science, 314(5805), 1564-1564.
3Huff, J. L., & Barry, P. A. (2003). B-virus (Cercopithecine herpesvirus 1) infection in humans and macaques: potential for zoonotic disease. Emerging infectious diseases, 9(2), 246.
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