Think Tank Research Project: The Orangutan Language Project

Forty frequently used body language signals were identified by British researchers who spent nine months observing orangutans in three European zoos. And the results have been compiled into the first ape dictionary  -  a guide on how our cousins chat to each other in the wild. It shows the apes have at least 25 signals or gestures for 'I want to play', for example  -  ranging from a back roll and somersault, to a yank of their hair or a bite of the air.

Other clowning gestures for play include placing objects on their heads, playing with their faces and raising their arms. Brushing with a hand means they want something to stop, while embracing and pulling at the same time means they want another ape to walk with them. Other gestures include hitting the ground, swatting, grabbing, and dangling upside down. Although studies of great ape body language have been carried out before, none has focused so closely on the intentional meanings of specific gestures. The findings don't just reveal how apes communicate  -  they also shed light on the origins of human speech millions of years ago.

What is Think Tank?

Think Tank is a place to think about thinking. It combines the appeal of orangutans, macaques, and other charismatic species with an interactive exploration of the question: "What is thinking?" Think Tank is unique in the zoo world in that it is about a biological process thinking, rather than a particular animal species or habitat.

How can scientists determine when animals are actually thinking? Scientists have different opinions about which animal behaviors actually involve thinking. Thinking, as defined in Think Tank, is said to occur if three elements exist: image, intention, and flexibility. For example, this scenario suggests that thinking is occurring:

A person wanting a fresh-baked chocolate chip cookie will have an image of that cookie in his head. With the intention of getting a cookie, he will set out for a bakery. When he gets there, he finds it is closed. Flexibility is shown when he can decide to buy the ingredients, go home, and bake his own cookies. In other words, when Plan A fails, he can switch to Plan B, or even Plan C.

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To help visitors understand thinking, Think Tank explores three domains of behavior Tools, Language, and Society for evidence of thinking.

In the introductory area of Think Tank's interpretive gallery, visitors are invited to examine their own beliefs about thinking. "Mission Control" presents the parts of the brain and their function. Visitors can also compare brain sizes of different animals, from an 82,000-pound (180,400 kg) finback whale to a 10-ounce (280 g) squirrel.

The next area of the exhibit, "Tools," investigates the definitions of tool use and presents examples of animals that appear to be using tools. It includes a display of hermit crabs that show complex tool-using behavior when choosing a shell, and a termite mound where visitors can practice using twigs and grass stems to "fish" like chimpanzees do for termites. This area also looks at human tool use, from early hominids to modern humans.

In Think Tank's orangutan enclosure, visitors can watch the behaviors of the orangutans, who climb and swing over from the Great Ape House on the "O Line" (a series of towers and cables). Inside Think Tank, the orangutans demonstrate their tool-using and problem-solving abilities. The orangutans are free to travel between Think Tank and the Great Ape House, however some prefer to stay in one location.

Visitors can view scientific studies in progress by watching the Zoo's behavioral researchers. In one of the studies, the orangutans use computers to learn a symbolic language. In this Orangutan Language Project (OLP), the researcher wants to know how orangutans think about the world. Think Tank staff will perform daily demonstrations and lead discussions on the research in progress.

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Does social behavior require thinking? Can animals invent new ways of doing things? These are the two main questions asked in the "Society" section of the exhibit, where the focus is on deception, cooperation, alliance-building, innovation, and conflict between animals. The intricate social structure of a leaf-cutter ant society, deceptive acts of several species, and an examination of whether innovation leads to tradition and culture in social groups, are explored in this area of Think Tank. Social strategies can also be observed in this section by watching Think Tank's Sulawesi macaques.

Think Tank is a trail-blazing, thought-provoking, interactive exhibit that gives visitors insight into the "behind-the-scenes" work of behavioral scientists. In creating this unique exhibit, Think Tank developers hope to inform visitors about this exciting field of scientific study, stimulate an interest in scientific careers, and instill a new respect for nature conservation.

The Orangutan Language Project

The Orangutan Language Project (OLP) explores the abilities of orangutans to use symbols and syntax to express their thoughts. Demonstrations of language research with the orangutans allow visitors to see scientific investigation in progress. Think Tank is the only place in the world where visitors have free access to observe scientists studying animal cognition.

The orangutans are learning to use a symbol-based language that is presented on a computer monitor. The monitor screen has large "buttons" that are big enough for orangutan fingers. The OLP dictionary contains a total of about 70 symbols. All symbols are abstract and have no visual relation to what they represent. In other words, the symbol for an apple looks nothing like an apple.

There are seven different categories of symbols and each category currently contains ten individual symbols. The symbol categories are:

* foods
* non-food objects
* proper names of people
* proper names of orangutans
* verbs
* adjectives
* Arabic numbers

Each category of symbols has its own specific exterior shape. For example, all food symbols have a rectangular exterior and all non-food object symbols have a circular exterior. A rectangle alone means "food" and a circle alone means "non-food object." Thus, each symbol can be broken down into its component parts just as a words are spelled using a series of letters. Individually, the interior components of each symbol are meaningless (like the letters of a word). It's the arrangement within the exterior shape that gives each symbol a specific meaning. In addition to the seven categories, there are symbols that mean "send," "clear," "yes/good," and "no/wrong."

The OLP dictionary can be expanded to as many symbols as the orangutans can learn. Currently, the orangutans are building their vocabularies. The next step will be to introduce syntax so that the individual symbols can be strung together to form simple sentences.

The orangutans participate in the OLP on a voluntary basis. There are no coercive or disciplinary elements to the program; orangutans are only reinforced with positive rewards. The animals are never coerced into working by being deprived of food, companionship, play time, or anything else.

Orangutan memory

While a great deal is known about human memory, we know little about how memory works in nonhuman primates. It appears that nonhuman primates rely on memory in such everyday tasks as foraging for food and recognizing familiar individuals. The purpose of this research is to investigate memory in orangutans.

When humans are asked to memorize a list of unrelated words in a series of trials, they begin to organize the words in idiosyncratic clusters. This phenomenon has been termed subjective organization, since the nature of the associations are unique to each person. This spontaneously-developed organization strategy increases the number of words that a person can remember. The crucial parts of this task are that the words are unrelated and that it requires free recall on the part of the person being tested. Unrelated words are necessary to prevent organization based on semantic categories (which we know humans will use). Free recall, in which the person is free to produce the list words in any order, allows the researcher to see what strategies the person used to organize the words.

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Subjective organization in nonhuman primates has not been studied, probably because of the difficulty in making a free recall task with animals that can't speak. However, it is possible to create a recognition memory task that allows animals that can't speak to produce the list items in any order. In this task, list items (photographs) are presented on a touch-screen video monitor. The orangutan is required to touch each item as it appears, in order to show that the item has been seen. Following the presentation of the list, all the list items appear in a random arrangement on the screen along with a set of items that were not on the list. The orangutan must touch the list items, and only the list items, in any order. Once all the list items have been touched, the orang utan is rewarded, and the next trial begins.

The first question being addressed is whether orang utans will develop an organizing strategy for long lists. In humans, the ability to develop such memory strategies does not begin to appear until the age of six or seven. It is not until ten or eleven that humans can utilize such strategies consistently and efficiently. If orang utans are able to develop an organizational strategy to help them learn a list, it would show that they are capable of sophisticated memory strategies.

Even if the orangutans fail to show signs of subjective organization, we can find out if they can use category information to organize lists. In other words, we can present lists that are made up of items that can be classified into categories (foods, insects, trees, animals). We suspect that orangutans will be able to use such category information to organize lists. If we find that these animals do this, we will be able to use that as a stepping stone to further explore the thinking ability of these animals.

Self-Awareness & Empathy in Orangutans

The purpose of this research project is to explore orangutan self-awareness. Do orangutans recognize themselves? Do they understand that different people see the world in different ways? Those are the questions that this research is trying to answer.

Does an orangutan recognize itself in a mirror? If so, it must have a concept of self. Mirrors were used in studies at the National Zoological Park to test whether orangutans recognize themselves in mirrors. While some definitely do, others seem to treat their reflections as if they were other orangutans.

To study whether orangutans are capable of empathy, we need to be able to identify if an orangutan can use its own experiences to understand that different people view the world in different ways. For example, can an orangutan use its own experience of visual impairment with a blindfold to understand that another individual cannot see when he or she wears a blindfold? Human children don't begin to understand this simple concept until at least the age three or four. The results with the orangutans show that they do understand that other individuals are visually impaired when blindfolded.

Another way orangutan empathy is being studied is to determine whether they can understand the goals and intentions of their caretakers. To test this, a situation is set up in which an orangutan sees a keeper trying to get an object placed just out of reach. The orangutans have access to tools (long sticks) that they previously have been able to use to get out-of-reach objects. If the orangutan helps by giving the keeper a tool, then the animal is obviously able to empathize with the keeper's goals and intentions.

Evidence of Thinking

Social interactions may offer some of the strongest evidence of thinking. Survival depends on fulfilling needs, but how does a social animal fulfill the needs of finding resources, safety, and reproduction when other members of the group are all trying to do the same things? The answer is strategic thinking.

Dealing with other individuals in a group can be complicated. Who can be trusted? Who can help? Who is the leader? Many individuals means many social possibilities. When there are multiple ways to achieve a social goal, it is likely that strategic thinking is occurring. To get what you want, planning and flexibility are the keys, and that means thinking.

The Strategic Thinking area of Think Tank considers hierarchies and beneficial relationships. In particular, four different goals of social living are explored:

* How to increase status in society
* How to join forces against a rival
* How to make up after a fight
* How to find a mate

Obtaining these social goals requires answers to several questions:

* Who is each individual (including age and sex) and to whom is each individual related?
* Who is dominant in which situations and who is subordinate in which situations?
* Where are resources located and who has access to them?
* What is your place in the hierarchy?

Once these questions are answered, this information must be used to select a series of behaviors that meet a certain goal.

The Strategic Thinking touch-screen computer in the Society of Think Tank challenges visitors to reach four social goals important to chimpanzees. Visitors roleplay life in a chimpanzee group by touching photos that illustrate certain behaviors.

Deception and Innovation as Evidence of Thinking

Deception and innovation are two activities that may provide evidence of thinking. Creating diversions, misinforming, and withholding information are all deceptive acts. In order to label a behavior "deceptive" or "innovative", a scientist must be very familiar with the normal range of behaviors for a particular species.

Deception is not always a behavior that shows thinking. For many species it is part of a feedback loop where a certain stimulus triggers the next activity. For instance, a plover will "fake" an injury to distract a predator away from its nest. This is deception, but all plovers use this same behavior and it is not learned. It shows little flexibility and is therefore not evidence of thinking.

There are good anecdotal examples of behaviors that appear to involve thinking-based deception. For instance, scientists have observed a baboon give a "false alarm." The baboon was being threatened and chased by other group members. To thwart the chasers, he stopped, stood up on his hind legs, and looked into the distance—the same behavior baboons exhibit when they see a predator or another baboon group. In this case there was no danger; the behavior got the other baboons to stop their chase and look in the same direction so the alarm-calling baboon could escape.

The formation of new behaviors (innovation) and the process by which they become traditions within a society may also be evidence of thinking. An example of innovation within a social group is when a wild female Japanese macaque began washing her food with water. The behavior was soon copied by others in the group. When infants began washing their food also, the behavior was passed on to a new generation and a tradition was born. Researching these types of innovation can take many years since new social traditions sometimes spread slowly through a population.