"Neural circuitry lets macaques figure out what's going on in social interactions
For many hours a day they pluck dirt, debris and bugs from each other’s fur. Between grooming sessions they travel in troops to search for food. When ignored by mom, they throw tantrums; when not ignored by zoo-goers, they throw feces.
Through these behaviors, monkeys demonstrate they understand the meaning of social interactions with other monkeys. They recognize when their peers are grooming one another and infer social rank from seeing such actions within their group..."
Read the full story on Scientific American's website at the link below.