Copepods drive large-scale trait-mediated effects in marine plankton
Copepods drive large-scale trait-mediated effects in marine plankton
复制标题
DOI：
10.1126/sciadv.aat5096
复制
发表时间：
2019-02
期刊：
影响因子：
13.6
通讯作者：
E. Selander;E. Berglund;P. Engström;F. Berggren;J. Eklund;S. Harðardóttir;N. Lundholm;W. Grebner;M. Andersson
中科院分区：
文献类型：
--
作者：
E. Selander;E. Berglund;P. Engström;F. Berggren;J. Eklund;S. Harðardóttir;N. Lundholm;W. Grebner;M. Andersson
海洋浮游动物结构浮游植物群落的警报信号。对捕食的恐惧可能比实际的捕食对食物网的影响更大。然而，在海洋浮游生物等单细胞主导的食物网中，非消耗性捕食者效应的机制和程度在很大程度上是未知的。我们报道了海洋浮游生物中化学诱导的捕食者效应的一般机制。桡足类是海洋中最丰富的浮游动物，它在海水中印有独特的极性脂类--桡足类化合物--这会在有害的甲藻中引发毒素的产生和生物发光。我们发现，该化合物还能在其他浮游植物中诱导出防御特征，诱导有害的藻类水华形成的硅藻产生10倍以上的毒素，并使形成菌落的硅藻减少一半的菌落大小。在东北大西洋进行的一项为期一年的研究表明，当桡足类丰富时，天然的聚足胺浓度高到足以诱导有害的藻类毒素和主要初级生产者的尺寸缩小。我们的结论是，海洋浮游生物将在盆地范围内构建更小、更具防御性的生命形式。
Alarm signals from marine zooplankton structure phytoplankton communities. Fear of predation may influence food webs more than actual predation. However, the mechanisms and magnitude of nonconsumptive predator effects are largely unknown in unicellular-dominated food webs such as marine plankton. We report a general mechanism of chemically induced predator effects in marine plankton. Copepods, the most abundant zooplankton in the oceans, imprint seawater with unique polar lipids—copepodamides—which trigger toxin production and bioluminescence in harmful dinoflagellates. We show that copepodamides also elicit defensive traits in other phytoplankton, inducing the harmful algal bloom-forming diatom Pseudo-nitzschia seriata to produce 10 times more toxins, and colony-forming diatoms to decrease colony size by half. A 1-year study in the northeast Atlantic revealed that natural copepodamide concentrations are high enough to induce harmful algal toxins and size reduction in dominant primary producers when copepods are abundant. We conclude that copepodamides will structure marine plankton toward smaller, more defended life forms on basin-wide scales.