Animal Minds; social adaptability in macaques (Animals)

by David Turell , Tuesday, June 25, 2024, 17:00 (130 days ago) @ David Turell

Forced by a hurricane removing shade:

https://www.science.org/doi/10.1126/science.adk0606?utm_source=sfmc&utm_medium=emai...

"Abstract:

Extreme weather events radically alter ecosystems. When ecological damage persists, selective pressures on individuals can change, leading to phenotypic adjustments. For group-living animals, social relationships may be a mechanism enabling adaptation to ecosystem disturbance. Yet whether such events alter selection on sociality and whether group-living animals can, as a result, adaptively change their social relationships remain untested. We leveraged 10 years of data collected on rhesus macaques before and after a category 4 hurricane caused persistent deforestation, exacerbating monkeys’ exposure to intense heat. In response, macaques demonstrated persistently increased tolerance and decreased aggression toward other monkeys, facilitating access to scarce shade critical for thermoregulation. Social tolerance predicted individual survival after the hurricane, but not before it, revealing a shift in the adaptive function of sociality."

***

"Discussion:

"We found that monkeys were persistently more tolerant of others in their vicinity and less aggressive for up to 5 years after Hurricane Maria. Relationships based on social tolerance became more numerous and predicted individual survival after the storm, especially during the hottest hours of the day. These findings support our hypothesis that the adaptive benefits of social tolerance are linked to accessing a thermoregulating resource—shade—in response to increased heat stress. Monkeys were not simply being passively “squeezed” into now-limited shaded spaces but instead showed a generalized increase in social tolerance, including outside of thermoregulatory contexts, suggesting a fundamental change in how they engaged with others. Notably, social tolerance did not predict survival before the hurricane, demonstrating that hurricane-induced drastic changes in ecological pressures altered the benefits individuals gain from social relationships. These results show that an extreme climatic event and its aftermath altered selective pressures on a social phenotype and identify ecosystem fluctuations as potential evolutionary drivers of sociality in group-living animals.

***

"Our study provides rare evidence of an abrupt change in selection on sociality in the face of a large and persistent ecological disturbance. These findings show the potential of social flexibility to provide resilience to rapid and unpredictable environmental fluctuations in animals and emphasize a dynamic link between the environment and fitness consequences of social behavior."

Comment: that the monkeys were able to change their social behavior when forced with survival issues is not surprising. "I have to tolerate them to have shade" is a self-serving decision. It does not represent empathy.