Bendett Yonatan, Hadany Lilach
School of Plant Sciences and Food Security Tel Aviv University Tel Aviv Israel.
Ecol Evol. 2025 Apr 16;15(4):e71129. doi: 10.1002/ece3.71129. eCollection 2025 Apr.
Conflicts between individuals of the same species are common in nature and are mostly resolved with limited aggression. Several theoretical studies, such as the Hawk-Dove (HD) game model, investigate the evolution of limited aggression expressed during conflicts between individuals. These studies mainly focus on the individuals involved in the conflict and their genes. Recently accumulating evidence indicates that microbes are associated with diverse functions of their host and can affect host behavior. Here we extend the classic HD game model to include both the hosts and their microbes, examining how natural selection acts on the microbes. We find that nonaggressive host behavior is more likely to evolve and spread in a population when induced by the microbes residing in the host, compared to nonaggressive behavior induced by host genes. Horizontal transmission allows microbes to colonize new hosts, making their success dependent on the fitness of both the host and its opponent. Therefore, selection on the microbes favors reduced host aggressiveness under wider conditions compared to selection acting on genes alone. Our results suggest that microbes may help explain the ubiquity of nonviolent conflict resolution. Consequently, factors that alter the microbial composition within hosts may affect the aggressiveness level in host populations.
同一物种个体之间的冲突在自然界中很常见，且大多通过有限的攻击行为得到解决。一些理论研究，如鹰鸽（HD）博弈模型，探讨了个体间冲突中表现出的有限攻击行为的进化。这些研究主要关注参与冲突的个体及其基因。最近越来越多的证据表明，微生物与其宿主的多种功能相关联，并能影响宿主行为。在此，我们扩展经典的HD博弈模型，将宿主及其微生物都纳入其中，研究自然选择如何作用于微生物。我们发现，与宿主基因诱导的非攻击性行为相比，当宿主内的微生物诱导时，非攻击性行为更有可能在种群中进化和传播。水平传播使微生物能够定殖新宿主，这使得它们的成功取决于宿主及其对手的适合度。因此，与仅作用于基因的选择相比，在更广泛的条件下，对微生物的选择有利于降低宿主的攻击性。我们的研究结果表明，微生物可能有助于解释非暴力冲突解决的普遍性。因此，改变宿主体内微生物组成的因素可能会影响宿主种群的攻击水平。
