Monkeys Show Threat-Sensitive Responses To Humans
Findings coming out of this article suggest that monkeys are able to distinguish between humans who pose a threat and those who do not. This study with wild monkeys in a national park in Ecuador presented the primates with humans engaged in three types of behavior (gathering, hunting, and researching). The results showed that monkeys had the strongest response to humans who posed as hunters. A finding such as this that adds to the understanding of how animals can serve as their own advocates is an interesting one for animal protectionists to consider.
[Abstract excerpted from original source.]
“Responding only to individuals of a predator species which display threatening behaviour allows prey species to minimise energy expenditure and other costs of predator avoidance, such as disruption of feeding. The threat sensitivity hypothesis predicts such behaviour in prey species. If hunted animals are unable to distinguish dangerous humans from nondangerous humans, human hunting is likely to have a greater effect on prey populations as all human encounters should lead to predator avoidance, increasing stress and creating opportunity costs for exploited populations. We test the threat sensitivity hypothesis in wild Poeppigi’s woolly monkeys (Lagothrix poeppigii) in Yasunı´ National Park, Ecuador, by presenting human models engaging in one of three behaviours ‘‘hunting”, ‘‘gathering” or ‘‘researching”. These experiments were conducted at two sites with differing hunting pressures. Visibility, movement and vocalisations were recorded and results from two sites showed that groups changed their behaviours after being exposed to humans, and did so in different ways depending on the behaviour of the human model. Results at the site with higher hunting pressure were consistent with predictions based on the threat sensitivity hypothesis. Although results at the site with lower hunting pressure were not consistent with the results at the site with higher hunting pressure, groups at this site also showed differential responses to different human behaviours. These results provide evidence of threat-sensitive predator avoidance in hunted primates, which may allow them to conserve both time and energy when encountering humans which pose no threat.”