According to dr. tomasello, one explanation for how chimpanzees learn to use a stick to fish for honey is that the skill is

The skill is an example of insightful problem solving by nonhuman primates.  
This problem sollving mechanism shows the fact that chimpanzees posses a certain level of intelligence that considerably higher compared to other mammals. This finding strengthens the evolutionary theory which conveys that humans are the evolved form of primates/

The result of evolution. Learned by watching their human caregivers use keys to open locks. An example of insightful problem solving by nonhuman primates.

I thought u was talking about a Chinese historical problem