Wild Bornean orangutan mothers travel farther and feed less to bring their young together for play sessions with similarly aged peers.
Researchers analyzed 15 years of data on 31 mother-offspring pairs, covering roughly 30,000 hours of observations. Mothers with offspring of comparable ages spent more time in the same areas than expected, and the youngsters played during these encounters, especially when the mothers were closely related.
The mothers increased their travel distance in the days before and after meetings, entering neighboring territories and returning home afterward. These movements occurred regardless of fruit availability and reduced the mothers’ feeding time, indicating a deliberate cost to their own foraging.
“Our study provides strong evidence that wild Bornean orangutan mothers adjust their ranging behavior to increase their offspring’s access to social play,” the researchers wrote. Experts noted that the findings align with orangutans’ known investment in offspring care and cognitive abilities, though the exact mechanisms of coordination remain unclear.
