Linking predator kairomones and turbulence: synergistic effects and ultimate reasons for phenotypic plasticity in Daphnia cucullata
Linking predator kairomones and turbulence: synergistic effects and ultimate reasons for phenotypic plasticity in Daphnia cucullata
复制标题
连接捕食者利他素和湍流：协同效应和水蚤表型可塑性的最终原因
DOI：
10.1127/0003-9136/2006/0167-0135
复制
发表时间：
2006
期刊：
影响因子：
--
通讯作者：
C. Laforsch
中科院分区：
文献类型：
--
作者：
R. Tollrian;C. Laforsch
僧帽蚤（Daphnia cucullata）盔状结构的季节变化已被研究了世纪。最近的研究表明，D.已经发现，cucullata可以减少捕食者造成的死亡率，可以由几种捕食性无脊椎动物释放的化学线索诱导。然而，它也已被证明，湍流诱导这一特点。这两种诱导线索的关系和相互作用尚不清楚。在这里，我们提出了实验室实验的结果表明，捕食者的线索和湍流可以协同作用。这两个因素相结合，诱导显着更大的反应，相比，每个因素单独，头盔达到了最大的尺寸在天然湖泊中发现。这一结果可能有助于解释在自然界中观察到的该物种的大头盔。湍流诱导背后的最终原因尚不清楚。通过检验D.僧帽水母能对游动的无脊椎动物产生的湍流做出反应。我们发现，直接接触异种性大型蚤和捕食性独眼巨人时，头盔的生长显著增加。单独考虑化学线索的处理并不能增加头盔对来自D.在这种情况下，大，或rCyclops。这些结果表明D.僧帽水母能够对游动的无脊椎动物发出的机械信号做出反应。因此，我们的研究表明，化学线索和湍流产生的捕食性无脊椎动物可能会协同作用，以诱导头盔作为有效的保护对无脊椎动物捕食。
The seasonal change in helmet size in Daphnia cucullata has been studied for over one century. Recently it has been shown that helmets in D. cucullata, which have been found to reduce predator caused mortality, can be induced by chemical cues released by several predatory invertebrates. However, it also has been shown that tur- bulence induces this trait. The relation and interplay of both inducing cues is not known. Here we present results from lab experiments showing that predator cues and turbulence can act synergistically. Both factors in combination induced significantly larger responses, compared to each factor alone, and helmets reached the maximum sizes found in natural lakes. This result might help to explain the observation of large helmets in this species in nature. The ultimate reason behind the turbulence induction is yet unknown. We link both induction factors to predation, as the ultimate reason, by testing the hypothesis that D. cucullata can respond to turbulence produced by swimming invertebrates. We found that helmet growth increased significantly in direct contact to both the heterospecific Daphnia magna and the predator Cyclops sp. Treat- ments which accounted for chemical cues alone did not increase helmet growth in re- sponse to cues from D. magna ,o rCyclops under these conditions. Together, these re- sults indicate that D. cucullata is able to respond to mechanical cues produced by swimming invertebrates. Thus, our study suggests that both chemical cues and turbu- lence generated by predatory invertebrates might act synergistically to induce helmets as effective protection against invertebrate predation.