Decision-makers can be described as economically rational (making consistent choices), or economically irrational (making choices that vary with the options available). As the extent to which animals can and do make rational versus irrational decisions remains unclear, we tested the decision-making strategies of female Nasonia vitripennis parasitic wasps in two behavioural contexts: oviposition and foraging. In our first experiment, to determine whether oviposition preferences changed depending on the options available, we presented females with a high and a medium-quality blow fly host to parasitize, and gave some females an additional low or very low quality 'decoy' host. Presence of decoy options did not affect females' oviposition choices, either in willingness to parasitize a host or the number of offspring laid. In our second experiment, we tested the effects of a low-quality decoy option on foraging preference for a high and a medium-quality sucrose concentration option. Here, presence of the low-quality decoy enhanced female preference for the high-quality option. Females therefore made economically rational decisions when ovipositing and economically irrational decisions when foraging. This difference in decision outcomes suggests that the cost/benefit ratio of making one type of decision over another may differ with the behavioural task.

中文翻译：

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决策的合理性取决于行为背景

决策者可以被描述为经济上理性的（做出一致的选择），或经济上的非理性（做出随可用选项而变化的选择）。由于动物能够并且确实做出理性与非理性决定的程度尚不清楚，我们测试了雌性 Nasonia vitripennis 寄生蜂在两种行为环境中的决策策略：产卵和觅食。在我们的第一个实验中，为了确定产卵偏好是否会根据可用选项而改变，我们向雌性提供了高质量和中等质量的吹蝇宿主进行寄生，并为一些雌性提供了额外的低质量或极低质量的“诱饵”宿主。诱饵选项的存在不会影响雌性的产卵选择，无论是寄生宿主的意愿还是产下的后代数量。在我们的第二个实验中，我们测试了低质量诱饵选项对高和中等质量蔗糖浓度选项的觅食偏好的影响。在这里，低质量诱饵的存在增强了女性对高质量选项的偏好。因此，雌性在排卵时做出了经济上合理的决定，而在觅食时做出了经济上不合理的决定。决策结果的这种差异表明，做出一种类型的决策相对于另一种类型的决策的成本/收益比可能因行为任务而异。因此，雌性在排卵时做出了经济上合理的决定，而在觅食时做出了经济上不合理的决定。决策结果的这种差异表明，做出一种类型的决策相对于另一种类型的决策的成本/收益比可能因行为任务而异。因此，雌性在排卵时做出了经济上合理的决定，而在觅食时做出了经济上不合理的决定。决策结果的这种差异表明，做出一种类型的决策相对于另一种类型的决策的成本/收益比可能因行为任务而异。