FOCUS_Language Without a Sound During language acquisition, gestures seem vital to learning how to speak. They help us emphasize and structure what we say. Simone Pika from the Humboldt Research Group at the Max Planck Institute for Ornithology in Seewiesen wants to know whether gestures were an evolutionary precursor of human language and how they develop. To investigate this question, the researcher studies the com- munication strategies of great apes in natural environments, but also corvids and human infants. TEXT CATARINA PIETSCHMANN n incredible cacophony starts making begging and appease- the highly-aroused situation of hunt- of vocalizations echoes ment gestures: he ducks down, sways ing, do they not increase their distance through the rainforest, backwards and forwards, whimpers like from the animals when it falls below followed by hectic scurry- a chimpanzee child, and makes a facial this minimum. ing. Chaos is in the air. Ba- expression called a fear grin. The mes- Yet Pika doesn’t need to get any boonsA have hunted down a small ante- sage: Don’t hurt me, but give me some closer to film the gestures that are ex- lope, but a group of chimpanzees im- of that delicious stuff. And it works! changed between the animals. The mediately snatches away their prey. As Bartok tears the antelope apart and 43-year-old is the Leader of the Hum- Bartok, the alpha male, lugs the carcass shares small pieces of the meat with boldt Research Group “Evolution of around, some members of his group both of them. Communication” at the Max Planck In- beg him to share some of the meat. stitute for Ornithology in Seewiesen. Bartok, however, wants to be the RESEARCHERS KEEP THEIR She wants to solve one of evolution’s first to eat, so he settles down with the DISTANCE biggest mysteries: how did human lan- dead animal less than four meters away guage evolve? from the blonde woman. Simone Pika “When you actually get to see some- According to one theory, our ances- has been following the chimpanzees for thing like this in the wild, you can’t tors initially gesticulated with each quite some time during her daily treks help sitting in the camp that night and other before using speech. That means through Uganda’s Kibale National Park, just smiling from ear to ear,” says Pika, they could have communicated simple and she can hardly believe that Bartok thinking back to that day. Because un- information using gestures. “But, like is sitting so close to her now. like in the days of the young Jane many of my colleagues, I now believe Two males have the courage to ap- Goodall, scientists no longer lure wild this to be a rather unlikely scenario, proach Bartok and the scientist. While chimpanzees with food, but instead because individuals use gestures to one of them simply sits down next to track them down in the rainforest day communicate with each other mainly the alpha male, opens up his out- after day, guided by the animals’ nests, stretched hand and then gently starts feeding grounds and calls, all the while Like all great apes, gorillas also communicate plucking at the antelope, the other making sure to keep an observer dis- via gestures. The animals use this form of male is less self-confident. Although he tance of at least seven meters. Only in communication mainly in relaxed settings and across short distances. also sits down next to Bartok, he then very rare and specific contexts, such as Photo: Simone Pika/MPI for Ornithology 18 MaxPlanckResearch 2 | 16 Without a Sound Photo: Simone Pika/MPI for Ornithology FOCUS_Language when they are in a relaxed setting and can touch or at least see each other,” says Pika. But what if an animal wants to warn other members of its group of a preda- tor, and the group is far away in the dense rainforest? “Then vocalizations are, of course, much more effective than gestures.” That is why most re- searchers now believe that calls and gestures evolved in parallel. While writing her doctoral thesis under the supervision of Michael To- masello at the Max Planck Institute for Evolutionary Anthropology in Leipzig, Pika studied the gestures used by go- rillas and bonobos in various wildlife parks and zoos across Europe. But is their behavior similar to that of their fellow apes living in the wild? Or do gestures. In a new study being conduct- Today, there is a scientific consensus animals in captivity gesticulate primar- ed with her postdoctoral fellow Dr. Eva that apes use gestures to communicate ily because they lack a natural environ- Luef, the researcher is therefore aiming with each other. Pointing gestures, ment and are constantly in each oth- to find out whether chimpanzees, like however, were considered to be an ex- er’s presence? humans, have certain greeting customs, clusively human trait until recently. Yet To find answers, the young research- and if so, whether these greetings vary chimpanzees living in zoos have been er had to observe her subjects in their depending on an individual’s social observed to clearly point to highly de- natural habitats. “In 2005, when I was rank within the group. Consequently, sirable food, such as grapes and banan- given the opportunity to study a group gestures would be relevant in situations as, indicating to their keepers: I want of chimpanzees in Kibale National in which humans, too, would talk to that! It appears that chimpanzees and Park, nothing could hold me back. I each other: in direct exchanges, when bonobos in captivity learn that they will always remember that very first individuals are in very close proximity can bring a human’s attention to a par- day: Not a single chimpanzee anywhere to each other. ticular object by pointing at it, and that in sight, but the forest was filled with In 2010, Pika received the Alexan- they will ultimately receive the object. their calls, which are known as pant- der von Humboldt Foundation’s Sofja This kind of exchange has only rarely hoots and can be heard hundreds of Kovalevskaja Award, which is endowed been observed in nature, and only be- meters away. The wild chimpanzees with 1.65 million euros. She uses these tween friends or between mothers and called out much more frequently than funds to study the evolution and devel- their offspring. their counterparts in captivity, indicat- opment of communication in three dif- ing to us that calls play a very different ferent model groups: in children grow- GROOM ME HERE! role in natural habitats,” Pika explains. ing up in different cultures; in great Pant-hoots let chimpanzees know apes, our closest living relatives; and in The pointing gestures that have been who is in which part of the forest and species that have a similarly complex observed in chimpanzees living in their with whom. The animals also use these social structure – corvids. Using this ap- natural environments mostly occur in characteristic calls to claim rich feeding proach, Pika aims to determine the de- the context of animals grooming each grounds for themselves. When greeting gree to which our ancestors had devel- other. Grooming is more than just a hy- each other, they use quieter pant- oped communication skills, and which gienic behavior: it plays an important grunts. Pika has observed that some an- factors are responsible for the fact that role in establishing and maintaining imals also accompany these grunts with only humans are capable of speech. social relationships. Simone Pika dis- Photo: Marlen Fröhlich/MPI for Ornithology 20 MaxPlanckResearch 2 | 16 Left The more independent young chimpanzees become, the less their mothers carry them around. By stretching out her arm and making eye contact, this chimpanzee mother is telling her child that it’s time to go to one of the safest places in the rainforest of Uganda’s Kibale National Park: onto mom’s back. Right Chimpanzees use more than 100 different types of gestures. Some gestures are used by only one single member of a group. The male chimpanzee Dolphi, for example, raises his arms vertically above his head to signal to the alpha male (front) that he should follow the group. covered that chimpanzees use distinct scratching gestures to let others know that they want to be groomed, but more importantly, they use them to sig- nal where. “This means chimpanzees know that their counterpart under- stands the meaning of the gesture,” says the Max Planck researcher. Many species of birds also use refer- ential gestures when performing court- ship displays – despite the fact that birds and humans sit on two very diver- gent branches of the evolutionary tree. Ravens are a prime example: not only are they intelligent and capable of learning, but they also use objects as pointing tools. Pika discovered that ra- vens pick up objects with their beaks with the intention of offering or show- ing them to other group members, or to attract the attention of a potential mate. And sometimes they just want to volve objects,” says Pika. This indicates own reach. They do so by scooting clos- scuffle with each other for it. that apes use pointing gestures only to er to their partner and presenting the “Children do that too – and chim- attract the attention of conspecifics, but part of their body that itches. Young panzees, surprisingly, don’t. They do never to inform them of something go- birds also enjoy spreading their wings scuffle for things, but they don’t hold ing on in their immediate surroundings. and sliding down a snowy slope on up objects to show or offer them to oth- Just like apes, ravens also groom their backs.