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Animal friendships and social bonds evolve over time as they do with humans

Recent research highlights the intricate social dynamics and friendships exhibited by group-living animals, including mutual aid and cooperation, which have captivated biologists for decades.

The evolution of these social bonds, often compared to human friendships marked by acts of kindness such as sharing food, has been a hot topic of debate among scientists. This particular study was led by experts from Stockholm University and the University of Neuchâtel.

A new take on animal cooperation

Historically, the study of animal cooperation has leveraged game theory, focusing on reciprocity — the idea that animals help those who have helped them. Despite over fifty years of research, existing models based on strict, immediate reciprocity have fallen short in explaining the nuanced reality of these social interactions.

The new study proposes a revolutionary model that mirrors more accurately the gradual formation of social bonds observed in nature. Researchers found that friendships evolve over time, strengthening as individuals engage in mutual aid and shared experiences.

These bonds, which can develop in both small and large groups, hinge on the opportunity for meaningful interactions within smaller subunits of the group.

Beyond reciprocity: Complexity of animal friendships

One of the most striking findings of this research is the proactive nature of group members in welcoming newcomers. The study suggests that group members do not only work to maintain existing relationships but also actively seek to establish new ones, thereby enhancing the group’s social fabric.

This challenges previous assumptions that new friendships form slowly, underscoring the dynamic and inclusive nature of animal social networks.

Professor Emeritus Olof Leimar of Stockholm University’s Department of Zoology, one of the lead researchers, emphasizes the importance of this discovery.

“How group members interact with new individuals is much discussed, and recently the idea that friendships with new individuals will develop only very slowly has been emphasized. Our analysis suggests that this need not be the case”, says Leimar.

“In fact, in the original discussions of the evolution of helping, the possibility that group members actively attempt to develop new friendships was put forward, and our analysis agrees with this,” Leimar adds. 

Developing social bonds in animal groups

Drawing parallels to the one-sided yet mutual relationship between mothers and their offspring, and supported by observed behaviors like food sharing among vampire bats, this study offers a robust theoretical foundation for understanding social bond dynamics in animal groups.

The findings not only provide a novel perspective on the evolution of helping behaviors but also encourage further exploration into how social ties are initiated and evolve across different species.

Professor Leimar expresses optimism about the impact of their work, stating, “We hope that our results will inspire biologists to further investigate the dynamics of social bonds in different group-living species, including studies on how new bonds are formed.”

Social circles and animal friendships in nature

In summary, this intriguing study upends our understanding of social bonds and cooperative behavior in group-living animals. By challenging the traditional models of reciprocity and unveiling a more nuanced view of friendship evolution, the researchers offer a compelling explanation for the dynamics of animal social networks.

Their findings, emphasizing the gradual development of social bonds and the proactive inclusion of new group members, enriches our comprehension of animal societies gives new direction for exploring the complex interplay of relationships in the animal kingdom.

This research underscores the importance of social cohesion and paves the way for future studies to further unravel the mysteries of animal behavior and evolution.

The full study was published in the journal Proceedings of the National Academy of Sciences.


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