Dissertation Research: Bird Song Divergence, Interspecific Territoriality, and Biogeography within a Sky Island Species Complex

论文研究：天空岛物种复合体中的鸟鸣分歧、种间领地性和生物地理学

• 批准号: 1011702
• 负责人: Rauri Bowie
• 金额: $ 1.36万
• 依托单位: University of California-Berkeley
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2010
• 资助国家: 美国
• 起止时间: 2010-05-15 至 2011-04-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1011702&HistoricalAwards=false
• 关键词: Dissertation; Research; Bird; Song; Divergence

Territorial animals face challenges in recognizing and responding to the threat posed by competitors. Particularly interesting for studies of territoriality are circumstances where two closely related animals in strong competition for resources use dramatically different signals to deter intruders. Such a situation occurs at the narrow boundary between the recently diverged Moreau's and Fuelleborn's sunbirds, which differ dramatically in territorial song and appear to show highly disparate levels of territoriality towards one another. Intriguingly, the geographical distribution of these two species suggests that one is expanding its range at the expense of the other across the 'sky island' forest isolates of the Udzungwa Mountains, Tanzania. This study integrates experimental and molecular approaches to examine the causes and consequences of aggressive asymmetries between populations. To examine support for alternate hypotheses that explain apparent aggressive asymmetry, the study will employ a series of playback experiments in which territorial subjects incur a simulated intrusion via the broadcast of a competitor's songs. Using DNA sequence data, the study will examine: 1) whether one species has recently invaded the Udzungwa Mountains at the expense of the other, and 2) the extent of gene flow between species.This study takes advantage of an unusual 'sky island' contact zone between species to test how signal evolution and territoriality interact, and how such interactions may influence the long-term outcomes of competition among ecologically similar species. It is rarely possible to examine how behavioral differences might scale up to impact extinction-recolonization dynamics in island-like distributions.

有领地意识的动物在识别和应对竞争对手构成的威胁方面面临挑战。对领地性的研究特别有趣的是，两只近亲动物在激烈的资源竞争中使用截然不同的信号来阻止入侵者。这种情况发生在最近分化的莫罗太阳鸟和富勒伯恩太阳鸟之间的狭窄边界上，它们在领土鸣叫方面差别很大，似乎对彼此表现出高度不同的领土水平。有趣的是，这两个物种的地理分布表明，其中一个物种正在以牺牲另一个物种为代价，扩大其活动范围，穿越坦桑尼亚Udzungwa山脉的“天空岛”森林隔离区。本研究结合实验和分子方法来研究种群间攻击性不对称的原因和后果。为了检验对解释明显攻击性不对称的其他假设的支持，该研究将采用一系列重放实验，在这些实验中，领地主体通过播放竞争对手的歌曲来模拟入侵。利用DNA序列数据，该研究将检验：1)一个物种最近是否以牺牲另一个物种为代价入侵了乌宗瓦山脉，以及2)物种之间的基因流动程度。本研究利用物种之间不寻常的“天空岛”接触区来测试信号进化和领土性如何相互作用，以及这种相互作用如何影响生态相似物种之间竞争的长期结果。很少有可能研究行为差异如何扩大影响岛屿分布中灭绝-再殖民化的动态。