Rojas Bibiana, Burdfield-Steel Emily, Pakkanen Hannu, Suisto Kaisa, Maczka Michael, Schulz Stefan, Mappes Johanna
Centre of Excellence in Biological Interactions, Department of Biology and Environmental Sciences, University of Jyväskylä, PO Box 35, Jyväskylä 40001, Finland
Centre of Excellence in Biological Interactions, Department of Biology and Environmental Sciences, University of Jyväskylä, PO Box 35, Jyväskylä 40001, Finland.
Proc Biol Sci. 2017 Sep 27;284(1863). doi: 10.1098/rspb.2017.1424.
Animals have evolved different defensive strategies to survive predation, among which chemical defences are particularly widespread and diverse. Here we investigate the function of chemical defence diversity, hypothesizing that such diversity has evolved as a response to multiple enemies. The aposematic wood tiger moth () displays conspicuous hindwing coloration and secretes distinct defensive fluids from its thoracic glands and abdomen. We presented the two defensive fluids from laboratory-reared moths to two biologically relevant predators, birds and ants, and measured their reaction in controlled bioassays (no information on colour was provided). We found that defensive fluids are target-specific: thoracic fluids, and particularly 2--butyl-3-methoxypyrazine, which they contain, deterred birds, but caused no aversive response in ants. By contrast, abdominal fluids were particularly deterrent to ants, while birds did not find them repellent. Our study, to our knowledge, is the first to show evidence of a single species producing separate chemical defences targeted to different predator types, highlighting the importance of taking into account complex predator communities in studies on the evolution of prey defence diversity.
动物已经进化出不同的防御策略来在捕食中生存，其中化学防御尤为广泛和多样。在此，我们研究化学防御多样性的功能，假设这种多样性是作为对多种敌人的反应而进化出来的。具有警戒色的木虎蛾后翅颜色醒目，并从其胸腺和腹部分泌不同的防御液。我们将实验室饲养的蛾子的两种防御液呈现给两种具有生物学相关性的捕食者——鸟类和蚂蚁，并在可控的生物测定中测量它们的反应（未提供颜色信息）。我们发现防御液具有目标特异性：胸液，尤其是其中所含的2-丁基-3-甲氧基吡嗪，能威慑鸟类，但对蚂蚁没有引起厌恶反应。相比之下，腹液对蚂蚁有特别的威慑作用，而鸟类并不觉得它们有排斥性。据我们所知，我们的研究首次表明单一物种产生针对不同捕食者类型的单独化学防御的证据，突出了在猎物防御多样性进化研究中考虑复杂捕食者群落重要性。
