Molina-Morales Mercedes, Martínez Juan G, Martín-Gálvez David, Dawson Deborah A, Burke Terry, Avilés Jesús M
Departamento de Zoología, Universidad de Granada, E-18071, Granada, Spain; Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, United Kingdom.
Evolution. 2014 Oct;68(10):3020-9. doi: 10.1111/evo.12471. Epub 2014 Aug 1.
One of the best-known outcomes of coevolution between species is the rejection of mimetic parasite eggs by avian hosts, which has evolved to reduce costly cuckoo parasitism. How this behavioral adaptation varies along the life of individual hosts remains poorly understood. Here, we identify for the first time, lifetime patterns of egg rejection in a parasitized long-lived bird, the magpie Pica pica and show that, during the years they were studied, some females accept, others reject, and some others modify their response to model eggs, in all cases switching from acceptance to rejection. Females tested in their first breeding attempt always accepted the model egg, even those individuals whose mothers were egg rejecters. A longitudinal analysis showed that the probability of egg rejection increased with the relative age of the female, but was not related to the risk of parasitism in the population. We conclude that ontogeny plays a fundamental role in the process leading to egg rejection in magpies.
物种间协同进化最著名的结果之一是鸟类宿主对拟态寄生卵的排斥，这种现象的进化是为了减少代价高昂的杜鹃寄生。这种行为适应性如何随个体宿主的一生而变化，目前仍知之甚少。在这里，我们首次确定了被寄生的长寿鸟类喜鹊（Pica pica）一生中排斥卵的模式，并表明，在研究它们的那些年里，一些雌性喜鹊接受模型卵，另一些则排斥，还有一些改变了它们对模型卵的反应，在所有情况下都是从接受转变为排斥。在首次繁殖尝试中接受测试的雌性喜鹊总是接受模型卵，即使那些母亲是排斥卵者的个体也是如此。纵向分析表明，排斥卵的概率随着雌性喜鹊的相对年龄增加而增加，但与种群中的寄生风险无关。我们得出结论，个体发育在导致喜鹊排斥卵的过程中起着至关重要的作用。
