Dissertation Research: ECOLOGICAL IMPLICATIONS OF HUMMINGBIRD FEEDING MECHANISMS

由于所有的生命都依赖于水，流体的运动在自然系统和工程系统中都是极其重要的。大体积液体中流动的物理原理已相当清楚，但我们对如何有效地移动极小体积的液体知之甚少。里科-格瓦拉和鲁比加最近证明，蜂鸟在进食时使用一种以前未知的方法来非常迅速地移动微量的液体。蜂鸟每天吃的花蜜是他们体重的两倍多。因此，蜂鸟是在生物医学和其他目的的工程中模仿有效的液体移动设备的主要自然例子。里科-格瓦拉和鲁贝加之前的工作预测了一秒钟内可以收集和运输多少液体。该项目将使用高速相机陷阱来测试这些预测，方法是测量以野生花卉为食的蜂鸟的实际花蜜提取速率(以微升/秒为单位)。结果将有两个好处：1)它们将确认一种流体传输方法的物理模型，该方法有可能用于微流体设备的工程；2)将提供对鸟类摄取花蜜的速度的限制如何塑造蜂鸟的行为、分布、生态和进化的洞察。该项目将有助于来自科学界代表性最低的群体之一的四名学生(拉美裔)的专业发展。该项目已经通过iNaturalist.org上名为“蜂鸟和花”的鸟类-植物互动数据库吸引了公众(参见http://www.inaturalist.org/projects/hummingbirds-and-flowers)，公开提供行为和生态数据)。

Since all life depends on water, the movement of fluids is profoundly important in both natural and engineered systems. The physics of flow in large volumes of fluids is fairly well understood, but we know less about how to move very small volumes of liquid efficiently. Rico-Guevara and Rubega recently showed that hummingbirds use a previously unknown method to move tiny volumes of fluids very rapidly while feeding. Hummingbirds eat more than twice their body weight in nectar daily. Thus, hummingbirds are a premier natural example to mimic in engineering effective fluid-moving devices for biomedical and other purposes. Rico-Guevara and Rubega's previous work generated predictions about how much fluid can be collected and transported in a second. This project will use high-speed camera traps to test those predictions by measuring actual rates of nectar extraction (in microliters/second) for hummingbirds feeding at wild flowers. The results will have two benefits: 1) They will confirm a model of the physics of a method of fluid transport that has potential for the engineering of microfluidic devices; and 2) will provide insight into how the limits on how fast birds can feed on nectar have shaped the behavior, distribution, ecology and evolution of hummingbirds. The project will contribute to the professional development of four students (Hispanics) from one of the most underrepresented groups in science. The project is already engaging members of the public through a database of bird-plant interactions called "Hummingbirds and flowers" on iNaturalist.org (see http://www.inaturalist.org/projects/hummingbirds-and-flowers), making behavioral and ecological data publicly available.