We’ve all laughed at nothing in particular just to keep the conversation going. Researchers in Zambia found that chimps do too. Their study, published in Emotion, observed chimpanzees and greater apes responding to other chimps through expressions deemed laughter. Similar to the laughter in human interaction, the study found chimp laughter to be shorter when conversational, longer when spontaneous, and ultimately serve to reinforce social bonds. The study also observed chimps in new groups to mimic the laughter of the others more than chimps in their established groups. Just like our conversational giggles in a new social setting, chimps use laughs and smiles to promote communication. This suggests that chimp social behavior is more complex and similar to humans than formerly believed. Try laughing the next time you go to the zoo and see if you can crack any other primate smiles.