Have you ever wondered if animals can communicate with each other? If they had a language of their own? Researchers have found that Geoffroy’s Marmosets are able to alert other marmosets of predators using alarm calls. Not only can they alert other marmosets of predators, but they can use varying alarm calls to distinguish between the kind of predator and the position of it. These alarm calls allowed other Marmosets to then take action that would protect them from the predator they were alerted to; Were it be looking in the grass for a snake or looking up for an aerial predator.
In order to study this behavior, researchers at the San Diego Zoo did a series of experiments using two groups of marmosets varying in size. They excluded any juveniles from the study because younger marmosets haven’t learned how to give or react to alarm calls properly. They then placed one of three predators in site of the marmosets: a taxidermized prairie falcon, a plastic great-horned owl, a coiled freeze-fried rattlesnake, and a freeze-dried rattlesnake ready to attack. The avian predators were always placed in a perched position as opposed to being moved as if they were flying or hunting. As soon as the predator was put into place, the researcher began recording both audio and visual data from the same distance every time the experiment was conducted. They repeated this experiment about 2-3 times a week over a three-month period. They recorded hundreds of alarm calls and used audio and visual analysis to distinguish between the alarm calls for different predators.
They found that marmosets use two different alarm calls for animals that would be on the ground and birds that could be perched in trees. Once the marmosets could distinguish which kind of predator it was, either in the trees or on the ground, they began to react accordingly: either searching the ground for potential threats or looking both up and down for any potential threats in the trees. This shows that non-human primates have been able to develop a sophisticated defense mechanism against any potential threats, whether it be on the ground or in the trees. This work contributes to the growing study of how animals communicate amongst themselves and highlight intriguing insights into the defense mechanisms of primates overall.
Petracca, M. M., & Caine, N. G. (2013). Alarm Calls of Marmosets (Callithrix geoffroyi) to Snakes and Perched Raptors. International Journal of Primatology,34(2), 337-348. doi:10.1007/s10764-013-9662-3
