Abang (orangutan)


Abang was an orangutan taught to make stone tools, as a part of a research experiment to determine if this ability is a characteristic unique to humans, the genus Homo, or to the family Hominidae.

Early life

Abang was illegally captured in Sarawak when he was about 1 year old. After being confiscated by authorities, he was taken with a female, Dayang, to England in 1967 to the Bristol Zoo.

Experiment

Aim and setup

The aim of the experiment was to teach an ape subject, through imitative learning, to use a stone to hammer a flake from a flint and use this flake as a tool to open a box. The experiment was divided into two stages where the subject was given demonstrations and then given the opportunity to do the activity him/herself. Stage-I's aim was tool-use, to get an ape to cut a cord to open a box, using a pre-made flake. Stage-II's aim was tool-making, to get an ape to make his/her own flakes and open the box with them. The demonstration and attempts were done with a sheet aluminum box. A mesh window made the food visible. The box had a lid secured by a cord inside the box, with the cord accessible via a slot.

Timeline

The experiment started in 1971. The experimental sessions were conducted in an indoor part of the ape’s cage, initially with both Abang and Dayang present. They proved to be a distraction to each other, thereafter only Abang was then used as a subject. Stage-I was conducted in 4 sessions from March 5 to March 19 with success starting at the end of the 2nd session. Stage-II was conducted in 7 sessions from March 23 to April 16 with success starting in the 6th session.

Conclusion

In the opinion of the researcher, while the experiment showed, “… a case of imitative learning it would be misleading to think of Abang’s behavior solely as parrot-fashion learning. … apes possess random exploratory activity and innovations which can lead to new successes.”