Neural Basis of Sun-Compass Navigation

导航是几乎所有动物的基本行为，长期以来，它在生理和行为上的精湛一直令人类观察者着迷。北极燕鸥从一极到另一极的长途迁徙，或者帝王蝶穿越北美的迁徙，都能激发人们的想象力，但即使是普通的果蝇，也能在开阔的沙漠上飞行20公里，这一壮举需要导航提示。众所周知，许多昆虫，包括蜜蜂和帝王蝶，都是利用太阳的位置来导航的；然而，通过研究果蝇，大量的遗传工具可以用来理解这种行为背后的神经生物学。这项研究将采用最先进的神经科学技术来识别让果蝇利用太阳定位的神经元，并在自然条件下测试实验室的发现。这项研究将为各种各样的学生提供许多培训和指导的机会。实验室成员将与当地高中生合作，在莫哈韦沙漠的一个野外地点研究果蝇的传播能力，重点是确定它们飞得多远、多快以及朝哪个方向飞。实验室方面的研究将培养本科生在广泛的前沿技术。这种综合方法将进一步理解大脑如何在一种古老的、重要的生态行为中处理视觉信息。更好地理解导航的计算策略可能对自主机器人的设计很重要。本研究将通过行为学、遗传学、生理学和生态学的方法来研究果蝇（Drosophila melanogaster）太阳导航的神经基础。虽然以前没有被认为是导航研究的模型，但实验室实验表明，果蝇可以利用太阳作为远距离方向的线索。在闭环飞行模拟器中，苍蝇会主动抓住一个固定角度位置的小亮点。每只苍蝇在最初起飞时采用不同的方向，如果飞行被短暂中断，个体将记住这种方向偏好。使用这个飞行模拟器，将通过尝试训练苍蝇偏好特定的航向来测试先前经验对后续航向偏好的作用。为了探索特定神经元的作用，将使用遗传方法来沉默细胞类别，同时在飞行模拟器中测量对太阳导航的影响。双光子成像和电生理学也将用于研究负责太阳罗盘导航的电路，并调查单个细胞的功能作用。为了将这些机械调查与自然行为联系起来，将进行一系列实地实验，并与外展工作相协调，以调查太阳罗盘导航在分散中的作用。总的来说，这些互补的方法将产生从细胞生理学到生态学的动物导航机制的理解。结果将阐明系统神经科学的基本问题，如感觉运动经验如何塑造未来的行为，同时也促进对苍蝇自然史的理解。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Navigation is a fundamental behavior for nearly all animals and has long fascinated human observers both in terms of its physiological and behavioral virtuosity. Long-distance migrations of arctic terns flying pole-to-pole or monarch butterflies crossing North America capture the imagination, but even the common fruit fly can travel 20 kilometers across over open desert, a feat that requires navigational cues. Many insects, including honey bees and monarch butterflies, are known to use the position of the sun to navigate; however, by studying fruit flies the large number of genetic tools available to understand the neurobiology underlying this behavior can be brought to bear. This research will employ state-of-the-art neuroscience techniques to identify neurons that allow fruit flies to orient using the sun and test laboratory findings under natural conditions. The research will provide many opportunities for the training and mentorship of a diverse pool of students. Working with local high school students, lab members will study the dispersal abilities of fruit flies at a field site in the Mojave Desert, focusing on determining how far and fast they fly and in which directions. Laboratory aspects of the research will train undergraduates in a wide-range of cutting-edge techniques. This integrative approach will further the understanding of how brains can process visual information in an ancient and ecologically important behavior. A better understanding of the computational strategies underlying navigation may be important for the design of autonomous robots.This research will examine the neural basis of sun navigation in fruit flies (Drosophila melanogaster) by employing behavioral, genetic, physiological, and ecological approaches. Although previously not considered a model for navigation research, laboratory experiments suggest that fruit flies can use the sun as a long distance orientation cue. In a closed-loop flight simulator, flies will actively hold a small, bright spot at a fixed angular location. Each fly adopts a different heading when they initially take off, and individuals will remember this orientation preference if flight is interrupted for short intervals. Using this flight simulator, the role of prior experience on subsequent heading preference will be tested by attempting to train flies to prefer particular headings. To explore the roles of specific neurons, genetic approaches will be used to silence cell classes while measuring the effect on sun navigation in a flight simulator. Two-photon imaging and electrophysiology will also be employed to study the circuits responsible for sun-compass navigation and investigate the functional role of individual cells. To relate these mechanistic investigations to natural behavior, a series of field experiments will be conducted, which will be coordinated with outreach efforts, to investigate the role of sun-compass navigation in dispersal. Collectively, these complementary approaches will yield a mechanistic understanding of animal navigation that ranges from cell physiology to ecology. Results will shed light on fundamental questions of systems neuroscience, such as how sensorimotor experience shapes future behavior, while also forwarding the understanding of fly natural history.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.