DISSERTATION RESEARCH: Offspring Recognition and Brood Parasitism in African Finches: Implications for Signal Mimicry and Diversification

非洲雀的后代识别和育雏寄生：信号模仿和多样化的含义。Winkler和Justin G.父母和子女之间的交流在鸟类中很普遍。然而，雏鸟在这种对话中使用的信号只在两个鸟类家族中经历了极端的精心设计，即雌雀和寄生雀。雌雀雏鸟的嘴型是令人难以置信的多样化;每个物种都拥有独特的斑点，颜色和上颚和舌头上的标记组合。与雌虫雏鸟一起饲养的Viduid雏鸟，其嘴部的标记与它们所利用的宿主物种的嘴部标记完全匹配。据推测，拟态的发生是因为饲养寄生虫的成本很高，而且因为自然选择偏爱歧视外国长相的后代的宿主父母。然而，到目前为止，有很少的证据表明，雏鸟识别在雌蝇和野生宿主种群的研究只有少数已经进行。以往的工作表明，食物的可用性，主机学习，和雏鸟表型可能会影响是否主机父母承认和拒绝雏鸟。结合实地工作的控制禽舍实验将有助于评估这些变量的相对重要性。已知年龄的宿主和寄生虫的圈养种群已经建立，坦桑尼亚的研究将允许测试雏鸟的辨别力。在整个鸟舍和野外工作中，将记录雏鸟形态在物种内和物种间的变化。除了告知我们对后代识别行为的理解外，这项研究的结果还将深入了解宿主-寄生虫相互作用以及影响动物信号进化的过程。

Offspring Recognition and Brood Parasitism in African Finches: Implications for Signal Mimicry and DiversificationDavid W. Winkler and Justin G. SchuetzCommunication between parents and offspring is widespread among birds. However, the signals that nestlings employ in this dialogue have undergone extreme elaboration in only two families of birds, the Estrildid finches and the brood parasitic Viduid finches. The mouth patterns of estrildid nestlings are incredibly diverse; each species possesses a unique combination of spots, colors, and markings on its palate and tongue. Viduid nestlings, which are raised alongside estrildid host nestlings, have mouth markings that precisely match those of the host species they exploit. Presumably, mimicry occurs because raising parasites is costly and because host parents that discriminate against foreign-looking young are favored by natural selection. However, to date, there is scanty evidence for nestling recognition in estrildids and only a few studies of wild host populations have been undertaken. Previous work suggests that food availability, host learning, and nestling phenotypes may influence whether host parents recognize and reject nestlings. Controlled aviary experiments in combination with fieldwork will help to assess the relative importance of these variables. Captive populations of known-age hosts and parasites have already been established, and research in Tanzania, where a viduid exploits more than one host species, will allow for tests of nestling discrimination. Throughout aviary and fieldwork, variation in nestling morphologies within and across species will be documented. In addition to informing our understanding of offspring recognition behavior, results from this research will provide insight into host-parasite interactions and the processes that affect the evolution of animal signals.