Collaborative Research: Perception and Use of Infrared Radiation by Insects

该项目将研究昆虫探测和响应红外光的能力，红外光是一种波长比可见光长的电磁辐射。从蜜蜂、甲虫和蝴蝶等多种昆虫中，我们知道动物进化出了多种感知和利用电磁波的策略。为感知或控制电磁波而进化的器官在复杂程度和效率上往往超过类似的人造装置。迄今为止，这一研究领域的大部分焦点都集中在昆虫感知较短波长的光的能力上；我们对动物对较长波的反应知之甚少，部分原因是研究光谱这一端的工具直到最近才普遍可用。在这项研究中，物理学家和生物学家将合作研究一些模型系统，包括飞蛾的触角和蝴蝶的特殊翼鳞，以了解昆虫如何感知和利用红外光。通过“仿生学”理解和利用自然设计概念将加深我们对复杂生物系统的认识，并激发创造新技术的想法。这项研究将为生物学和物理学的研究生提供纳米技术方面的培训机会。该项目的目标是了解昆虫感知和响应红外光能力的物理机制，并获得可用于创造新型红外材料、设备和系统的工程见解。红外信号可能在各种各样的昆虫行为中发挥着关键而未被充分认识的作用。本项目将通过对两个系统的分析，为昆虫对宽带热辐射和窄带指纹红外辐射的感知和响应能力提供定量的认识：(1)超多样性部落Eumaeini（鳞翅目）蝴蝶物种翅膀上的气味垫和斑块；(2)不同蛾种的触角上有专门的感受器，能够以较高的波长特异性和效率捕捉红外光。模式昆虫将利用多学科研究平台进行研究。红外感应器官将通过单感器电生理记录和行为生物测定来识别，并使用光谱和时间控制的红外刺激。红外传感器官的形态将使用扫描电子显微镜和x射线显微断层扫描进行研究。传感器的光学特性将使用傅里叶变换红外光谱、红外显微镜和时域有限差分电磁波模拟来研究。利用纳米和微加工技术制作红外传感微结构的高保真复制品或其缩放模型，系统分析传感器的材料特性、结构和排列如何影响红外探测的灵敏度和波长特异性。对昆虫感知和响应红外信号的机制的详细研究以前还没有进行过，对这一现象的更深入了解可能会为科学界催化一个新的研究领域。该项目将扩大我们对自然选择如何塑造精巧的适应性行为和结构的理解。

The project will investigate the ability of insects to detect and respond to infrared light, which is a type of electromagnetic radiation with wavelengths longer than that of visible light. It is known from insects as diverse as honeybees, beetles and butterflies that animals have evolved diverse strategies to perceive and utilize electromagnetic waves. Organs evolved for perceiving or controlling electromagnetic waves often surpass similar man-made devices in both sophistication and efficiency. To date, most of the focus in this area of research has been on the abilities of insects to perceive shorter wavelengths of light; much less is known about how animals respond to longer wavelengths, in part because the tools to investigate this end of the spectrum have only recently become commonly available. In this research, physicists and biologists will collaborate in studying a few model systems, including the antennae of moths and specialized wing scales of butterflies, to understand how insects can perceive and utilize infrared light. Understanding and harnessing natural design concepts through "biomimicry" will deepen our knowledge of complex biological systems and inspire ideas for creating new technologies. The research will provide training opportunities in nanotechnology for graduate students in biology and physics. The objectives of the project are to understand the physical mechanisms underlying the ability of insects to perceive and respond to infrared light, and to obtain engineering insights that can be used to create novel infrared materials, devices and systems. Infrared signals may play a critical and underappreciated role in a wide variety of insect behaviors. This project will provide a quantitative understanding of insects' abilities to sense and respond to broadband thermal radiation and narrowband fingerprint infrared radiation by analyzing two systems: (1) Scent pads and patches on the wings of butterfly species in the hyperdiverse tribe Eumaeini (Lepidoptera: Lycaenidae) that show extremely broadband, close-to-unity absorptivity/emissivity, and (2) Specialized sensilla on the antennae of different moth species that are able to capture infrared light with high wavelength-specificity and efficiency. The model insects will be studied using a multidisciplinary research platform. The infrared-sensing organs will be identified using single-sensillum electrophysiological recordings and behavioral bioassays with spectrally and temporally controlled infrared stimulation. The morphology of the infrared-sensing organs will be studied using scanning electron microscopy and X-ray micro-tomography. The optical properties of the sensilla will be studied using Fourier transform infrared spectroscopy, infrared microscopy, and finite-difference time-domain electromagnetic wave simulations. High-fidelity replicas of the infrared-sensing microstructures or their scaled models will be fabricated using nano- and micro-fabrication to systematically analyze how material properties, structures and arrangement of the sensilla affect the sensitivity and wavelength-specificity of infrared detection. Detailed studies of the mechanisms by which insects perceive and respond to infrared signals have not been carried out before, and a greater understanding of this phenomenon is likely to catalyze a new area of research for the scientific community. The project will expand our understanding of how natural selection can shape exquisitely adapted behaviors and structures.