Observational Learning in Orangutan Cultural Transmission Chains

1. Observational Learning in Orangutan Cultural Transmission Chains Marietta Dindo, Tara Stoinski, and Andrew Whiten A Presentation by Madeline Mow and Briana Schmidt

2. Understanding Culture across Species • The Oxford English Dictionary summarizes “culture” to mean the “distinctive ideas, customs, social behavior, products, or way of life of a particular society, people, or period.” • With growing evidence for unique cultural traditions in other species, the exact definition of “culture” has been the topic of recent debate. • A range of definitions are currently in use to describe a wide variety of aspects relating to culture in non-human animals.

3. Understanding Culture across Species

4. Why Orangutans? • Orangutans have social, yet solitary behavior. • There aren’t that many opportunities to learn from others. • Cultural transmission has been seen more prevalently in a mother-infant context. • There’s not much experimental evidence in the wild.

5. Subjects • Seven males and four females from Zoo Atlanta were used. • Two of the males (Allen and Chantek) were trained as models. • The orangutans ranged from 2 to 38 years old.

6. Apparatus and Procedure • The model was trained to open the box by sliding or lifting. • 10 trial sessions. • The model demonstrated the method in front of an observer. • 20 trial sessions. • The observer moved to another cage for the test session. • 20 trial sessions. • The test session was terminated if nothing happened after 15 min. • After the test session, the subject became the model for the next group member. Orangutan Copy Cats

7. Lift • In the lift chain, the subjects were not all from the same social group. • The researchers used videotaped demonstrations for observation sessions.

8. Slide • The third observer was dominant over the demonstrator. • There was a mesh barrier between the two for the first 10 trials. • The last subject did not try to open the box for 15 minutes, so the trial was terminated.

9. Results • In the lift group, all subjects successfully lifted the door 20/20 trials. • In the slide group, only half of the subjects slid the door open 20/20 trials. • The third subject only completed 19/20 trials correctly. • The fourth subject did not complete his trials with either method.

10. Discussion • Results confirm orangutans are capable of learning novel foraging behaviors by observing the actions of others. • The experiment also shows orangutans can learn from video-taped demonstrations. • Previous studies on mimicry in orangutans show less faithful transmission of knowledge between individuals. • High accuracy may be due to the simplicity of the task.

11. Discussion Questions • Does such a simple behavior as demonstrated by these groups of orangutans deserve to be referred to as “culture”? • Which definition of culture mentioned at the beginning of the presentation best describes the behaviors of the orangutans in the experiment by Dindo, Stoinski, and Whiten? • Assuming the presence of culture in other species, is the value and “uniqueness” of human culture undermined? • Should humans intervene in wild populations to conserve particular cultural groups, instead of the species as a whole?

12. Thank you for your attention! Here’s our way of showing our gratitude!