A new mathematical model suggests that cooperation between different species can unexpectedly fall apart, even when conditions seem ideal for working together. This finding challenges our understanding of how species interact and cooperate in nature.
The Puzzle of Cooperation in Nature
Charles Darwin found cooperation in nature puzzling. It seemed to go against his idea of natural selection, where only the fittest survive. Over the years, scientists have used game theory to understand why animals and plants sometimes help each other instead of just competing.
Usually, cooperation works best when it doesn’t cost much or when the benefits are big. When it becomes too expensive to cooperate, species stop doing it. This idea has helped explain relationships like those between plants and their pollinators.
But a new study published in PNAS Nexus shows that cooperation can break down in surprising ways.
Unexpected Twists in Cooperative Behavior
Dr. Christoph Hauert, a mathematician at the University of British Columbia, explains: “As we began to improve the conditions for cooperation in our model, the frequency of mutually beneficial behaviour in both species increases, as expected. But as the frequency of cooperation in our simulation gets higher—closer to 50 per cent—suddenly there’s a split. More cooperators pool in one species and fewer in the other—and this asymmetry continues to get stronger as the conditions for cooperation get more benign.”
This “symmetry breaking of cooperation” has been seen in models before. But this new model is different because it lets individuals in each group interact more naturally.
Dr. Hauert and his colleague Dr. György Szabó from the Hungarian Research Network used computer models to place individuals from two species on separate grids facing each other. This setup allows cooperators to form groups and interact more with other cooperators, reducing their exposure to cheaters who might take advantage of them.
“Because we chose symmetric interactions, the level of cooperation is the same in both populations,” says Dr. Hauert. “Clusters can still form and protect cooperators but now they need to be synchronized across lattices because that’s where the interactions occur.”
Why It Matters
This research is important for several reasons:
- It challenges our understanding of how species cooperate in nature.
- It could help explain sudden changes in behavior between species that work together.
- The model might be useful for studying other complex systems, not just in biology but in physics and social sciences too.
Dr. Szabó points out: “The odd symmetry breaking in cooperation shows parallels to phase transitions in magnetic materials and highlights the success of approaches developed in statistical and solid state physics. At the same time the model sheds light on spikes in dramatic changes in behaviour that can significantly affect the interactions in complex living systems.”
This new insight into cooperation could help scientists better understand and predict changes in ecosystems. It might also have applications in fields like economics or social policy, where understanding cooperation is crucial.
As we face global challenges that require cooperation on a large scale, models like this one could provide valuable insights into when and why cooperation might suddenly break down, even under seemingly favorable conditions.
Quiz:
- What happens to cooperation in the model when conditions become more favorable?
- Who found cooperation in nature puzzling, according to the article?
- What field does Dr. Szabó compare the symmetry breaking in cooperation to?
Answer Key:
- It unexpectedly breaks down or becomes asymmetrical between species
- Charles Darwin
- Phase transitions in magnetic materials
