Males sometimes engage in fights over contested resources such as access to mates; in this case, fighting behaviour may be adjusted based on the value they place on the females. Resource value (RV) can have two components. First, males can assess the quality of females, which constitutes an objective assessment of RV. Second, internal state such as previous mating experience can also influence motivation to fight thus constituting a subjective assessment of RV. If mating opportunities are scarce and available females have a major impact on the lifetime reproductive success of males, then fighting can be fatal; in this situation it is uncertain whether males would adjust fighting behaviour based on RV. We found that both female quality, that is, virginity (objective component of RV) and male mating status (subjective component of RV) influenced fighting intensity between males of the entomopathogenic nematode Steinernema longicaudum which engage in lethal fights. Male nematodes were more likely to engage in fighting and fought longer and more frequently in the presence of virgin (high-quality) females than in the presence of mated (lower-quality) females. Male mating status was also found to influence fighting behaviour: mated males were the winners in staged fights between mated and virgin males. Mated males may have superior fighting ability (greater resource-holding potential), but RV asymmetries between mated and virgin males cannot be excluded. Males were more likely to win when they were resident, but we did not find a significant interaction effect between male mating and residency status.

中文翻译：

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雄性昆虫病原线虫致命战斗中资源价值的客观和主观成分

雄性有时会为争夺配偶等有争议的资源而打架；在这种情况下，战斗行为可能会根据他们对女性的重视程度进行调整。资源价值 (RV) 可以有两个组成部分。首先，男性可以评估女性的素质，这构成了对RV的客观评估。其次，内部状态（例如以前的交配经验）也会影响战斗动机，从而构成对 RV 的主观评估。如果交配机会稀少，而可用的雌性对雄性一生的生殖成功有重大影响，那么战斗可能是致命的；在这种情况下，雄性是否会根据 RV 调整战斗行为是不确定的。我们发现这两种女性品质，也就是，童贞（RV 的客观组成部分）和雄性交配状态（RV 的主观组成部分）影响昆虫病原线虫 Steinernema longicaudum 的雄性之间的战斗强度，这些线虫从事致命的战斗。与交配的（低质量）雌性线虫相比，雄性线虫更有可能参与战斗，并且在处女（高质量）雌性存在的情况下战斗时间更长，频率更高。还发现雄性交配状态会影响战斗行为：已交配的雄性是已交配和处女雄性之间分阶段战斗的赢家。交配的雄性可能具有优越的战斗能力（更大的资源持有潜力），但不能排除交配和处女雄性之间的 RV 不对称性。男性在常住时更有可能获胜，