Orangutans value treats more when linked to sounds of peers laughing, study finds

Captive orangutans preferred food linked to the sound of their peers laughing, according to a study in the journal Biology Letters. Researchers worked with six orangutans at two zoos, playing recordings of play and laughter or environmental sounds such as wind before the apes searched bowls for treats. The apes later favoured bowls associated with laughter, suggesting emotions influence learning.