Acclimation conditions may affect the fighting ability of individuals involved in agonistic contests through their oxidative status. For instance, exposure to high temperatures might increase the metabolic rate of opponents and their production of damaging reactive oxygen species (ROS). Animals investing more strongly in antioxidant defences to minimize the damaging action of heat-induced ROS may therefore be deprived of antioxidant defences and hence less able to sustain fight effort during subsequent contests. Here, we examined the interplay between acclimation temperature, oxidative status and fight outcome in male field crickets, Gryllus bimaculatus. Relative to nonfighting males, males involved in agonistic contests staged at 27 °C showed lower antioxidant defences when acclimated to cool conditions (19 °C) and higher oxidative damage when acclimated to higher temperatures (27 and 35 °C). This shows that fights represent an oxidative challenge, which is differently regulated depending on acclimation temperature. Furthermore, males with higher antioxidant capacity were more likely to win contests. Antioxidant defences therefore appear to contribute to the resource-holding potential of opponents, presumably because they reflect their ability to sustain the physical effort associated with fighting. Moreover, antioxidant defences may be used by opponents to assess their relative fighting ability to terminate contests before related costs become too high. However, antioxidant asymmetry reflected fight outcome only when both opponents were previously acclimated to the same thermal conditions. In contrast, when opponents were acclimated to different temperatures, males from the higher temperature were more likely to win these fights. This suggests that the effects of thermal conditions on fight outcome are independent of and preponderant over the effects of antioxidant defences. Antioxidant defences may still be an important determinant of fight outcome in the wild when opponents, occupying homogeneous habitats, are exposed to comparable conditions before fighting.

中文翻译：

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抗氧化不对称性和驯化温度独立反映雄性蟋蟀的战斗结果

驯化条件可能会通过氧化状态影响参与激动竞赛的个体的战斗能力。例如，暴露在高温下可能会增加对手的代谢率及其破坏性活性氧 (ROS) 的产生。因此，在抗氧化防御方面投入更多资金以最大程度地减少热诱导的 ROS 的破坏作用的动物可能会被剥夺抗氧化防御，从而在随后的比赛中难以维持战斗力。在这里，我们研究了雄性蟋蟀 Gryllus bimaculatus 的驯化温度、氧化状态和战斗结果之间的相互作用。相对于不打架的男性，参与在 27 °C 下进行的激动竞赛的雄性在适应凉爽条件 (19 °C) 时表现出较低的抗氧化防御能力，而在适应较高温度 (27 和 35 °C) 时则表现出更高的氧化损伤。这表明打架代表了一种氧化挑战，它根据适应温度的不同受到不同的调节。此外，具有较高抗氧化能力的男性更有可能赢得比赛。因此，抗氧化防御似乎有助于增强对手的资源持有潜力，大概是因为它们反映了他们维持与战斗相关的体力消耗的能力。此外，对手可以使用抗氧化防御来评估他们的相对战斗能力，以便在相关成本变得过高之前终止比赛。然而，只有当两个对手之前都适应了相同的热条件时，抗氧化不对称才能反映战斗结果。相比之下，当对手适应不同的温度时，来自较高温度的雄性更有可能赢得这些战斗。这表明热条件对战斗结果的影响与抗氧化防御的影响无关并占优势。当对手占据同质栖息地，在战斗前暴露于类似条件时，抗氧化防御可能仍然是野外战斗结果的重要决定因素。这表明热条件对战斗结果的影响与抗氧化防御的影响无关并占优势。当对手占据同质栖息地，在战斗前暴露于类似条件时，抗氧化防御可能仍然是野外战斗结果的重要决定因素。这表明热条件对战斗结果的影响与抗氧化防御的影响无关并占优势。当对手占据同质栖息地，在战斗前暴露于类似条件时，抗氧化防御可能仍然是野外战斗结果的重要决定因素。