Spider monkeys share insider knowledge to locate ripe fruit

Researchers who tracked Geoffroy's spider monkeys in Mexico's Yucatan from 2012 to 2017 found that individuals move between small subgroups in a fission‑fusion system, carrying foraging experience with them so information about where and when fruit ripens spreads through the population.

Researchers observed Geoffroy's spider monkeys in Mexico's Yucatan Peninsula and report that individuals share information about where and when fruit ripens. Field teams from Heriot‑Watt University, the University of Edinburgh and the National Autonomous University of Mexico tracked subgroup composition, travel routes and fruit ripening between 2012 and 2017. The monkeys live in a fission‑fusion social system in which subgroups form, dissolve and reform, and researchers found that moving between subgroups spreads foraging knowledge across the population. Mathematical models used in the study indicated that this pattern helps the group build a broader picture of ripe fruit locations than any single subgroup could maintain. Key observations: - Each subgroup typically visited different parts of the forest and often had distinct knowledge of particular fruit patches. - Individuals that changed subgroups carried their prior foraging experience with them, enabling food information to circulate among groups. - Fruit ripening was spatially and temporally uneven, so pooling observations from many individuals improved population‑level awareness of where ripe fruit could be found. - The researchers used mathematical models to show that fission‑fusion dynamics increased the group's aggregate understanding of ripening schedules. Summary: This work frames the fission‑fusion social structure as a mechanism of collective intelligence that lets nonlinguistic primates aggregate distributed knowledge to locate scattered resources. The study also highlights conservation implications, noting that information sharing relies on movement across wide, connected forest areas. Researchers suggest examining other species with fluid social networks to see whether similar information pooling occurs.