Showing instructional videos to monkeys in the wild has proven to be a resounding success, finds a new study that describes the first known usage of such videos in an animal's native habitat.
The study, published in the latest issue of Biology Letters, opens the door to further instruction of animals, both wild and captive.
"I believe that videos and other instructional tools can indeed accelerate the learning of non-human primates and also other non-human animals," lead author Tina Gunhold told Discovery News.
"Such instructional tools might even have the potential to be used in conservation programs where animals in captivity have to learn certain skills before they get released to the wild," added Gunhold, who is a researcher in the University of Vienna's Department of Cognitive Biology.
For the study, she and colleagues Andrew Whiten and Thomas Bugnyar produced videos showing marmosets demonstrating different foraging techniques used to open an artificial fruit. They then set up an elevated box in the Atlantic Forest of Aldeia, Pernambuco, Brazil. Marmosets living in the forest, who had never before seen the marmosets featured in the videos, could scale a viewing platform to watch the footage.
The primates "were immediately attracted to the video box," Gunhold said. They lined up in front of it like kids fixated on a television show, with one big difference.
"They need to be constantly on alert and have to scan their surroundings for potential danger," she explained. "Therefore, their attention span is quite short."
Some of the marmosets could view the entire video, but others were just shown a static image with no instructional value.
The marmosets were then given a chance to open the artificial fruit themselves. Those that watched the instructional video performed the task much more successfully. It is probable that they also taught others what they learned.
"Common marmosets represent an ideal subject species to study social learning, as they live in small family groups, show high levels of social tolerance and exhibit a cooperative breeding system, where the father and other family members take great care of the infants," Gunhold said.
"Consequently," she added, "young individuals have access to a big ‘information network' within the family and ample opportunities to learn from both parents and siblings."
Instructional videos have already been used as enrichment for captive animals, such as chimpanzees, gorillas, zebra finches, and Japanese macaques. Differences in visual systems can affect the success of such efforts, since some animals literally see the world differently than humans do. Marmosets, for example, do not process colors precisely the same way, so the researchers presented the videos in grey scale.
Some animals might also think that the demonstrator on the screen is a live, present animal that could pose a threat. For the new study, however, the marmosets seemed to know that the demonstrators were not there in the flesh.
Scottish Primate Research Group member Erica van de Waal, commenting from a savanna full of vervet monkeys, told Discovery News that the "instructional video technique is great," especially from a research standpoint, since it gives scientists a better look at how animals learn.
Charles Snowdon, a professor of psychology and zoology at the University of Wisconsin, Madison, agrees with van de Waal. He also said, "It is a major advance to demonstrate that video techniques can facilitate social learning in the wild."
"The implications are several," he continued. "For example it is important to teach rehabilitated or reintroduced animals what foods are valuable and how predators are to be avoided. This method can facilitate that teaching by understanding better what variables are important to wild and to reintroduced animals in being able to learn how to forage, on what foods to forage and how to recognize and avoid predators."
"Thus, there are several important applications of this method for future work."