Abang (orangutan)
Abang is 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. [1]
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. [1]:298
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. [1]:298
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. [1]:299–304
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.” [1]:305