Animals compete in contests over limited resources, and contestants with greater fighting ability, or resource-holding potential (RHP), typically win contests. Contest strategies have evolved to balance contest costs with the benefit of winning resources. Sometimes, contestants decide to leave by estimating their opponent's relative RHP. This strategy (mutual assessment) is cost-effective because it allows weaker opponents to leave contests against formidable opponents before accruing higher costs. However, acquiring reliable information can be costly. Here, we showed that in snapping shrimp (Alpheus angulosus) contests, contestants assessed relative RHP quickly and cost-effectively by assessing their opponent's recent contest success. By staging 26 contests between randomly matched individuals and 24 contests between RHP-matched individuals, we determined that snapping shrimp assessed their opponent's RHP during initial contest phases but no longer assessed relative RHP during escalated phases. Then, after staging 24 contests between individuals with contest experience the day prior, we found that snapping shrimp integrated RHP and recent contest success to make contest decisions. This strategy facilitated fast and accurate judgments when the recent winner was also larger but often resulted in the larger individual retreating when facing a small recent winner. Notably, these systematic biases were corrected when RHP differences were stark. Taken together, our findings demonstrate that by assessing recent contest success early in a contest, snapping shrimp can avoid risky contests. Furthermore, by integrating recent contest success with direct observations of RHP, contestants avoid losing contests prematurely. Similar assessment strategies may be widespread, because they circumvent risky contests while minimizing premature defeats from weaker recent winners.

中文翻译：

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获胜者效应和转换评估策略有助于在领土竞赛中做出快速而节俭的决定

动物在争夺有限资源的比赛中竞争，具有更高战斗能力或资源持有潜力 (RHP) 的参赛者通常会赢得比赛。竞赛策略已经演变为平衡竞赛成本和赢得资源的好处。有时，参赛者通过估计对手的相对 RHP 来决定离开。这种策略（相互评估）具有成本效益，因为它允许较弱的对手在产生更高的成本之前离开与强大的对手的竞争。但是，获取可靠信息的成本可能很高。在这里，我们展示了在捕捉虾 (Alpheus angulosus) 比赛中，参赛者通过评估他们的对手最近的比赛成功来快速且经济高效地评估相对 RHP。通过在随机匹配的个人之间举办 26 场比赛和在 RHP 匹配的个人之间举办 24 场比赛，我们确定抓虾在初始比赛阶段评估对手的 RHP，但在升级阶段不再评估相对 RHP。然后，在前一天有比赛经验的个人之间进行了 24 场比赛后，我们发现抓虾综合了 RHP 和最近的比赛成绩来做出比赛决策。当最近的赢家也较大时，这种策略有助于快速准确的判断，但在面对近期较小的赢家时，往往会导致较大的个人撤退。值得注意的是，当 RHP 差异明显时，这些系统性偏差得到了纠正。总之，我们的研究结果表明，通过在比赛早期评估最近的比赛成功，抢虾可以避免危险的比赛。此外，通过将最近的比赛成功与 RHP 的直接观察相结合，参赛者可以避免过早输掉比赛。类似的评估策略可能很普遍，因为它们规避了风险竞赛，同时最大限度地减少了较弱的近期获胜者的过早失败。