Abstract：
AbstractHosts and brood parasites are a classic example of conflict. Parasites typically provide no offspring care after laying eggs, imposing costs on hosts. Female subsocial wasps (Ammophila pubescens) alternate between initiating their own nests and using an \"intruder\" tactic of replacing eggs in nests of unrelated conspecifics. Hosts can respond by substituting new eggs of their own, with up to eight reciprocal replacements. Remarkably, intruders usually provision offspring in host nests, often alongside hosts. We used field data to investigate why intruders provision and to understand the basis of interactions. We found that intruders could not increase their fitness payoffs by using the typical brood parasite tactic of not provisioning offspring. Intruders using the typical tactic would benefit when hosts provisioned in their stead, but their offspring would starve when hosts failed to provision. Although some hosts obtained positive payoffs when intruders mistakenly provisioned their offspring, on average utilizing a conspecific nest represents parasitism: hosts pay costs while intruders benefit. Hosts and intruders used the same tactic of egg replacement, but intruders more often laid the final egg. Selection should favor better discrimination of offspring, which could lead to repeated cycles of costly egg replacement.
摘要：
摘要宿主和育幼寄生虫是冲突的典型例子。寄生虫通常在产卵后不提供后代护理，将费用强加给主机。雌性亚社会黄蜂（Ammophilapubescens）在启动自己的巢穴和使用“入侵者”策略替换无关物种巢中的卵之间交替出现。主机可以通过替换自己的新鸡蛋来响应，多达八个互惠替换。值得注意的是,入侵者通常在寄主巢中提供后代，经常在主机旁边。我们使用现场数据来调查入侵者提供的原因并了解相互作用的基础。我们发现，入侵者无法通过使用典型的不提供后代的育苗寄生虫策略来增加其健身收益。使用典型策略的入侵者将在主机代替主机时受益，但是当宿主无法提供时，他们的后代会挨饿。尽管当入侵者错误地提供其后代时，一些宿主获得了积极的回报，平均而言，利用特定的巢穴代表着寄生：宿主支付成本，而入侵者则受益。宿主和入侵者使用了相同的换蛋策略，但入侵者更经常下蛋。选择应该有利于更好地区分后代，这可能会导致重复的昂贵的鸡蛋更换周期。
