NSF-BSF: The biomechanics of long-distance flight in large beetles: Do smaller individuals fly better?

昆虫对世界的农业和森林有着巨大的影响。它们的主要传播机制是飞行，有些昆虫能够长时间飞行，使它们能够在一次飞行中传播几十英里的距离。本研究将研究幼虫的生长条件如何导致成年甲虫体型的变化，以及这种体型的变化如何影响它们的扩散能力和长时间飞行的耐力。这项工作的优点在于它旨在了解昆虫在飞行过程中的非定常空气动力学与其能量消耗之间的关系。尖端的工具将用于测量和模拟与昆虫大小的扑翼飞行相关的非定常空气动力学和飞行能量学。这项研究的见解有望揭示导致害虫在受感染地区之间传播的因素，从而为森林和公园设计基于科学的管理计划。它还将为具有改进的长时间飞行能力的高效扑翼无人机的设计要求提供指导方针。这项工作是跨学科的（生物学、工程学），将促进以色列和美国本科生和研究生之间的协同国际合作。这项研究的结果将通过同行评议的期刊和科学会议向科学界传播，并通过两国的社交媒体、网站和外展项目向公众传播。由于对昆虫在前扑翼飞行过程中与风之间复杂的气动相互作用的了解有限，提高昆虫飞行耐力的生理和气动机制尚不清楚。该研究将研究芒果茎螟虫（Batocera rufomaculata）的飞行行为、空气动力学和能量学，重点关注种内体重变化如何影响通过飞行远距离分散的能力。rufomaculata是一种大型蛀树甲虫，其幼虫在无花果树的茎内发育。与从活的寄主树中生长出来的较大的成虫相比，在死的寄主树中发育的营养剥夺的幼虫会变成更小的成虫，具有更好的长距离飞行能力。该研究假设，由于空气动力学和扑翼运动学的有利比例，体型较小的甲虫更有效地进行远距离飞行。为了验证这一假设，这些甲虫将被拴在一个风洞里，以它们喜欢的飞行速度飞行，在一个设置中允许它们的扑动运动学（使用高速摄像机），它们在飞行过程中产生的力（使用力传感器），以及在它们的非定常尾流中形成的流场（使用粒子图像测速法，PIV），同时使用基于13C同位素的技术测量它们的代谢能量消耗。这些数据将与甲虫前扑翼飞行的数值模拟相补充，为甲虫与流体的相互作用特性提供基准。最后，利用无线电遥测技术对野外甲虫的飞行进行跟踪，并对飞行相关性状的异速性进行评价。该结果有望揭示幼虫发育与昆虫飞行性能之间关系的决定过程。该项目由生物科学理事会综合有机体系统部生理机制和生物力学项目以及刺激竞争性研究的既定计划（EPSCoR）共同资助。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。

Insects have a tremendous effect on the world’s agriculture and forests. Their main dispersal mechanism is by flight, and some insects are capable of prolonged flights enabling them to disperse distances of tens of miles in a single flight. This study will examine how larval growth conditions leads to variation in the body size of adult beetles and how this variation in body mass affects their dispersal capabilities and endurance for prolonged flights. The merit of the proposed work is its aim at understanding the relationship between the unsteady aerodynamics of insects during flight and their energy expenditure. Cutting edge tools will be used to measure and model the unsteady aerodynamics and flight energetics associated with flapping flight at an insect size scale. The insights from the study are expected to shed light on the factors contributing to dispersal of pest insects between infected areas, allowing design of science-based management programs for forests and parks. It will also provide guidelines for the design requirements for efficient flapping unmanned aerial vehicles with improved prolonged flight capabilities. The work is interdisciplinary (Biology, Engineering) and will foster a synergistic international collaboration between Israeli and US undergraduate and graduate students. The results of the study will be disseminated to the scientific community in peer-reviewed journals and scientific conferences and to the general public through social media, websites and outreach programs in both countries. The physiological and aerodynamic mechanisms improving flight endurance in insects are unclear due to limited understanding of the complex aerodynamic interaction between them and the wind during forward flapping flight. The proposed research will examine the flight behavior, aerodynamics, and energetics of the mango stem borer (Batocera rufomaculata), focusing on how intraspecific variation in body mass affects the ability to disperse large distances by flight. B. rufomaculata is a large tree-boring beetle with larvae developing inside the stem of fig trees. Nutrient-deprived larvae developing inside dead host trees emerge as smaller adults with improved long-distance flight capabilities compared to larger adults emerging from live host trees. The study hypothesizes that smaller beetles are more efficient long-distance flyers due to favorable scaling of aerodynamics and flapping kinematics. To test this hypothesis, the beetles will be tethered in a wind tunnel to fly at their preferred flight speed, in a set-up allowing correlation of their flapping kinematics (using high-speed cameras), the forces they produce during flight (using force transducers), and the flow fields formed in their unsteady wake (using particle image velocimetry, PIV) while measuring their metabolic energy expenditure using a technique based on a 13C isotope. These data will be complemented with numerical simulations of the beetle in forward flapping flight, providing benchmarks for the fluid-beetle interaction characteristics. Finally, the flight of beetles in the field will be tracked using radio telemetry, and the allometry of flight-related traits will be evaluated. The results are expected to reveal the processes determining the relationship between larval development and insect flight performance.This project is jointly funded by the Physiological Mechanisms and Biomechanics Program in the Division of Integrative Organismal Systems, Directorate for Biological Sciences, and the Established Program to Stimulate Competitive Research (EPSCoR).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.