There is something fascinating about this video where a monkey seems to be teaching a human (or at least uses a human) to crush leaves. The man should watch closely. We previously saw how monkeys have a much more efficient way to peel bananas.
The monkey could be playing or using the human for the task. Either way, it is rather riveting.
There is growing evidence of various species using tools – a task once thought to distinguish humans from the rest of the animal kingdom.