Study finds orangutans value food rewards more when hearing laughter

Researchers have found that laughter sounds can change how orangutans feel about food rewards. The study, published in Biology Letters, involved 25 captive orangutans. Scientists from Indiana University, the University of Portsmouth, and the University of Hanover led the research.

In the experiment, orangutans were shown two bowls. Each bowl had a material hiding a food reward inside. One material was paired with recorded orangutan laughter. The other was paired with a different sound. The orangutans chose the bowl connected to laughter more often.

The results suggest that hearing positive sounds made the animals value that choice more highly. Like humans, orangutans produce laughter sounds with open mouths and repeated breathing. The study adds to what scientists know about how emotions affect decision-making in great apes.