Laboratory of Fundamental and Applied Research in Chemical Ecology (FARCE), Institute of Biology, University of Neuchâtel, Rue Emile-Argand 11, 2000, Neuchâtel, Switzerland.
J Chem Ecol. 2014 Apr;40(4):320-4. doi: 10.1007/s10886-014-0426-0. Epub 2014 Apr 24.
The great spotted cuckoo (Clamator glandarius) is an important brood parasite of carrion crows (Corvus corone corone) in northern Spain. We recently found that, unlike what is commonly known for cuckoo-host interactions, the great spotted cuckoo has no negative impact on average crow fitness in this region. The explanation for this surprising effect is a repulsive secretion that the cuckoo chicks produce when they are harassed and that may protect the brood against predation. Here, we provide details on the chemical composition of the cuckoo secretion, as well as conclusive evidence that the dominating volatile chemicals in the secretion are highly repellent to model species representative of common predators of the crows. These results support the notion that, in this particular system, the production of a repulsive secretion by the cuckoo chicks has turned a normally parasitic interaction into a mutualistic one.
大斑杜鹃（Clamator glandarius）是西班牙北部普通乌鸦（Corvus corone corone）重要的巢寄生者。我们最近发现，与人们通常对杜鹃与宿主相互作用的了解不同，在该地区，大斑杜鹃对普通乌鸦的平均适应度没有负面影响。这种惊人效应的解释是杜鹃雏鸟在受到骚扰时会产生一种排斥性分泌物，这种分泌物可能会保护雏鸟免受捕食。在这里，我们提供了关于杜鹃分泌物化学成分的详细信息，并提供了确凿的证据，证明分泌物中的主要挥发性化学物质对代表常见乌鸦捕食者的模型物种具有很强的驱避性。这些结果支持了这样一种观点，即在这个特定的系统中，杜鹃雏鸟产生排斥性分泌物，将原本寄生的相互作用转变为互利的相互作用。
