The primate laugh is given in playful contexts, and as such has a strong similarity to the human laugh.

You should know as much as you can about the human species if you have a hand in designing human society.

Female bonobos form a strong sisterhood. They rule through female solidarity.

Human morality is unthinkable without empathy.

I have often noticed how primate groups in their entirety enter a similar mood. All of a sudden, all of them are playful, hopping around. Or all of them are grumpy. Or all of them are sleepy and settle down. In such cases, the mood contagion serves the function of synchronizing activities.

The sturdiest pillars of human morality are compassion and a sense of justice.