Tsao Yu-Jen, Okuyama Toshinori
Department of Entomology, National Taiwan University, Taipei, Taiwan.
Behav Processes. 2012 Sep;91(1):1-7. doi: 10.1016/j.beproc.2012.04.012. Epub 2012 May 24.
Antlion larvae are typically considered as trap-building predators, but some species of antlions always forage without using pits or only sometimes use pits to capture prey; they can ambush prey without pits. This study examined a species that switches its strategy between pit-trapping and ambushing and asked the mechanism behind the switching behaviour. A dynamic optimization model incorporating tradeoffs between the two strategies was built. The tradeoffs were prey capture success and predation risk (both are higher when pit-trapping). The model predicted that antlions should use the trap-building strategy when their energy status is low and should use the ambush strategy when their energy status is high. These predictions as well as an assumption (i.e., predation risk associated with pit-trapping is higher than that associated with ambushing) of the model were empirically confirmed. The results suggest that antlions flexibly switch between pit-trapping and ambushing to maximize their fitness by balancing the costs and benefits of the two strategies.
蚁狮幼虫通常被视为筑陷阱的捕食者，但有些蚁狮种类总是不借助陷阱觅食，或者只是有时利用陷阱捕获猎物；它们不设陷阱也能伏击猎物。本研究考察了一种在陷阱诱捕和伏击两种策略之间切换的蚁狮种类，并探究了这种切换行为背后的机制。构建了一个纳入两种策略之间权衡的动态优化模型。权衡因素为猎物捕获成功率和捕食风险（陷阱诱捕时两者都更高）。该模型预测，蚁狮在能量状态低时应采用筑陷阱策略，而在能量状态高时应采用伏击策略。这些预测以及模型的一个假设（即与陷阱诱捕相关的捕食风险高于伏击相关的捕食风险）得到了实证证实。结果表明，蚁狮通过平衡两种策略的成本和收益，在陷阱诱捕和伏击之间灵活切换，以实现自身适应性的最大化。
