Orangutans arrange playdates for their young just like humans. It's a hidden cost of solitary living.

A study published in PNAS reveals that Bornean orangutan mothers intentionally arrange playdates for their offspring, despite the costs involved. Researchers observed 31 young orangutans over 15 years, noting that mothers planned routes to meet other mothers with similar-aged young. These gatherings occurred infrequently, averaging once every 20 days, and were often influenced by kinship. The findings suggest that orangutans, like humans, face hidden costs of solitary living, emphasizing the importance of social interactions for young individuals.