Watching a couple instructional videos might be the quickest way to learn makeup tips, magic tricks, and how to moonwalk. Now, researchers show that monkeys in the wild can learn skills by watching videos too. Monkey see, monkey do. The findings are published in Biology Letters this week.
People used to think that culture and behavioral traditions were unique to humans, but from primates to meerkats to cockatoos, the evidence for the social transmission of information in non-human animals is mounting. Recent studies have found that primates can learn solutions to problems from watching videos in the lab. The approach has never been tried in the wild.
To see if wild common marmosets (Callithrix jacchus) can learn problem solving skills from others, a trio of researchers led by Tina Gunhold from the University of Vienna tested 12 family groups—that’s a total of 108 monkeys—in the Atlantic Forest of Aldeia in Pernambuco, Brazil, using video footage and a fruit-snatching task.
First, they trained a couple of captive monkeys to either pull open a drawer (pictured below, a) or push up a lid (b) to reach a fruity reward. The researchers recorded these marmoset teachers and displayed the videos on a laptop screen in an opaque plastic box on a platform where wild marmosets frequent. Six of the groups got to watch video demonstrations showing the unfamiliar marmosets pulling open the drawer or pushing up the lid. As controls, the other half were shown static images of marmosets next to fruit. The team then watched what happened when they placed the plastic box of treats on the platform in front of the video box.
Monkeys in the video-demo groups were more successful in finding the fruit than the controls, and they were also more likely to use the technique shown by the on-screen monkeys later, acting as teachers for other family members. However, as soon as one monkey mastered the task, it was impossible to tell whether the others were learning from the video or from their relative: "We think it's a combination of both," Gunhold tells New Scientist. Of the one dozen marmosets who were able to open the box, only one did it by figuring it out on his own.
Here’s a short movie of monkeys watching monkey movies:
Images: T. Gunhold et al., Royal Society 2014