Department of Neurobiology and Behavior, Cornell University, Ithaca, NY 14853, USA.
Proc Biol Sci. 2023 Feb 22;290(1993):20222489. doi: 10.1098/rspb.2022.2489. Epub 2023 Feb 15.
Signals mediate competitive interactions by allowing rival assessment, yet are often energetically expensive to produce. One of the key mechanisms maintaining signal reliability is social costs. While the social costs of over-signalling are well known, the social costs of under-signalling are underexplored, particularly for dynamic signals. In this study, we investigate a dynamic and olfactory-mediated signalling system that is ubiquitous among mammals: scent marking. Male house mice territorially scent mark their environment with metabolically costly urine marks. Competitive male mice are thought to deposit abundant scent marks in the environment. However, we recently identified a cohort of low-marking males that win fights. We hypothesized that there may be social costs imposed on individuals who under-invest in signalling. Here we find that scent mark investment predicts fight dynamics. Winning males that produce fewer scent marks prior to a fight engage in more intense fights that take longer to resolve. This effect appears to be driven by an unwillingness among losers to acquiesce to weakly signalling winners. We, therefore, find evidence for rival assessment of scent marks as well as social costs to under-signalling. This supports existing hypotheses for the importance of social punishment in maintaining optimal signalling equilibria. Our results further highlight the possibility of diverse signalling strategies in house mice.
信号通过允许竞争对手评估来介导竞争相互作用，但通常生产成本高昂。保持信号可靠性的关键机制之一是社会成本。虽然过度信号的社会成本是众所周知的，但信号不足的社会成本尚未得到充分探索，特别是对于动态信号。在这项研究中，我们研究了一种在哺乳动物中普遍存在的动态和嗅觉介导的信号系统：气味标记。雄性家鼠用代谢成本高昂的尿液标记来划定领地。竞争雄性老鼠被认为会在环境中大量留下气味标记。然而，我们最近发现了一群低标记的雄性老鼠，它们在战斗中获胜。我们假设，在信号投资不足的个体身上可能会施加社会成本。在这里，我们发现气味标记投资可以预测战斗动态。在战斗前产生较少气味标记的获胜雄性老鼠会进行更激烈的战斗，并且需要更长的时间才能解决。这种影响似乎是由于失败者不愿意默认信号较弱的胜利者。因此，我们发现了对手评估气味标记以及信号不足的社会成本的证据。这支持了社交惩罚在维持最佳信号平衡中的重要性的现有假设。我们的结果进一步强调了家鼠中存在不同信号策略的可能性。
