Kroon Annemarie, Veenendaal René L, Bruin Jan, Egas Martijn, Sabelis Maurice W
Institute for Biodiversity and Ecosystem Dynamics, Section Population Biology, University of Amsterdam, P.O. Box 94084, 1090 GB, Amsterdam, The Netherlands.
Naturwissenschaften. 2008 Dec;95(12):1195-8. doi: 10.1007/s00114-008-0442-4. Epub 2008 Aug 27.
Diapause in arthropods is a physiological state of dormancy that is generally thought to promote survival during harsh seasons and dispersal, but it may also serve to avoid predation in space and time. Here, we show that predation-related odours induce diapause in female adult spider mites. We argue that this response allows them to move into an area where they are free of enemies, yet forced to survive without food. Spider mites are specialised leaf feeders, but--in late summer--they experience severe predation on leaves. Hence, they face a dilemma: to stay on the leaf and risk being eaten or to move away from the leaf and risk death from starvation and thirst. Female two-spotted spider mites solve this dilemma by dramatically changing their physiology when exposed to predation-associated cues. This allows them to disperse away from leaves and to survive in winter refuges in the bark of trees or in the soil. We conclude that the mere presence of predation-associated cues causes some herbivorous mites to seek refuge, thereby retarding the growth rate of the population as a whole: a trait-mediated indirect effect that may have consequences for the stability of predator-prey systems and for ecosystem structure.
节肢动物的滞育是一种生理休眠状态，通常认为它有助于在恶劣季节生存和扩散，但它也可能用于在空间和时间上躲避捕食。在此，我们表明与捕食相关的气味会诱导雌性成年叶螨进入滞育状态。我们认为这种反应使它们能够迁移到一个没有天敌的区域，但被迫在没有食物的情况下生存。叶螨是专门以叶片为食的，但在夏末，它们在叶片上会遭受严重的捕食。因此，它们面临两难境地：留在叶片上有被吃掉的风险，或者离开叶片有因饥饿和口渴而死亡的风险。雌性二斑叶螨通过在接触到与捕食相关的线索时显著改变其生理状态来解决这个两难问题。这使它们能够从叶片上分散开来，并在树皮或土壤中的冬季避难所中生存。我们得出结论，仅仅是与捕食相关线索的存在就会导致一些植食性螨类寻求避难所，从而减缓整个种群的增长速度：这是一种性状介导的间接效应，可能会对捕食者 - 猎物系统的稳定性和生态系统结构产生影响。
