Theory expects contestants to adjust their investment in fighting in line with the perceived value of a resource. Thus, we expect to see an increase in contest duration or aggressive actions if the subjective value of the resource is estimated to be high relative to occasions where the value is estimated to be low. Although this expectation is well established in theory, we know little about how contestants structure their contests over resources in the wild: in particular, how variation in resource availability affects how contestants invest in fights. The objectives of this study were twofold: to examine whether (1) the structure of male–male fights varied with presence and abundance of oestrous females in the population and (2) there was an association between investment in fighting and mating success, during fights between fallow deer, Dama dama. Subordinate but not dominant contestants increased their rate of attacking actions when there were oestrous females in the population. However, there was no association between dominant or subordinate contest actions and variation in the number of oestrous females on any single day. Regarding mating success, dominant males that increased their attack rate during fights were more likely to achieve a mating than those that did not, although this investment in attacks was not associated with the number of matings obtained. Conversely, mating success was associated with a reduction in the number of parallel walks for subordinate contestants. Therefore, subordinate males achieved more matings when ritualized display behaviour was reduced or omitted from the contest. These results suggest that a desperado effect may be present, and that contestants use an estimate of resource value rather than opponent quality when investing in contests.

中文翻译：

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比赛行为因休耕鹿的繁殖机会和繁殖成功而异

Theory 期望参赛者根据资源的感知价值调整他们在战斗中的投资。因此，如果相对于估计值较低的情况，估计资源的主观价值较高，我们预计比赛持续时间或攻击性行为会增加。尽管这种期望在理论上已经确立，但我们对参赛者如何围绕野外资源构建竞赛知之甚少：特别是，资源可用性的变化如何影响参赛者在战斗中的投资方式。这项研究的目的有两个：检查（1）雄性和雄性争斗的结构是否随着人群中发情雌性的存在和数量而变化，以及（2）在争斗期间，对争斗的投资与交配成功之间是否存在关联在小鹿之间，达玛达玛。当人群中有发情的女性时，从属但不占主导地位的参赛者会增加他们的攻击行为。然而，在任何一天的主要或次要竞争行为与发情女性数量的变化之间没有关联。关于交配成功率，在战斗中增加攻击率的占优势的雄性比那些没有提高攻击率的雄性更有可能实现交配，尽管这种对攻击的投资与获得的交配数量无关。相反，交配成功与下属参赛者平行行走次数的减少有关。因此，当仪式化的展示行为被减少或从比赛中省略时，下属雄性获得了更多的交配。这些结果表明可能存在亡命之徒效应，