RII Track-4:NSF: Ultrafast Gripping and Release Mechanisms in Slingshot Spider Legs

球体蜘蛛，也被称为弹弓蜘蛛(SS)，是一个迷人的微小蜘蛛家族，大约针头大小，利用3-D锥形蛛网作为超高速弹弓捕捉飞行的昆虫。弹弓蜘蛛是已知的为数不多的蜘蛛类动物之一，它们活跃地使用一种工具(网)来加速速度，速度是猎豹的10倍。它们的腿和爪子可以承受超过体重100倍的力，并能在不到一毫秒的时间内启动弹弓运动。研究弹弓蜘蛛腿和爪子的解剖结构将使我们能够确定小型、快速响应机械系统的关键设计元素。通过奥本大学化学工程系的Symone Alexander博士和她的研究团队以及史密森研究所国家自然历史博物馆(NMNH)的Hannah Wood和Jonathan Coddington博士的合作，工程学和生物学方法将被用于识别、编目和连接不同物种的弹弓蜘蛛的独特特征。通过这项工作，我们将开发和实施尖端建模和成像技术，以创建处理和分析精细或敏感材料的新技术，所有这些都受到SS及其独特的猎物捕获策略的启发。这个研究基础设施改进Track-4 EPSCoR研究人员项目将为奥本大学的一名助理教授提供奖学金，并为一名研究生提供培训。该项目将与史密森学会国家自然历史博物馆(NMNH)的研究人员合作进行。这项工作的目标是：(1)利用微型计算机断层扫描(Micro-CT)来识别使SS能够在更长的时间内承受较大拉力的腿节形态；(2)使用Micro-CT来识别使SS能够高速抓取/释放丝质的爪子形态；以及(3)比较使用和不使用弹弓运动的近缘毛虫物种，以了解锁存形态的演变以捕获猎物。该项目将把这些发现与高速视频数据结合起来，以提供对SS猎物捕获的多尺度、机械的理解。宿主站点NMNH为比较密切相关物种的形态提供了一个独特的机会。该项目将通过加速获得蜘蛛形态和生物力学方面的基本交叉专业知识，极大地促进SS负荷和释放机制的探索。这项工作还将通过揭示承受高张力和快速响应环境刺激所需的形态来推进基础知识。探索SS腿的形态，特别是研究较少的近端关节，将导致识别出一种能够承受大载荷、亚毫秒级响应时间的轻型、小型生物力学系统，从而启发新的微机械系统和响应执行器的设计。对爪子形态的研究将揭示超高速抓取技术的设计参数，这种技术可以产生高摩擦力，而不会破坏脆弱的材料。此外，关于异体寄生虫物种的比较形态将有助于识别新物种，扩大NMNH收藏，并为SS超快猎物捕获的进化提供新的见解。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Theridiosomatids, also known as Slingshot Spiders (SS), are a fascinating family of tiny arachnids, about the size of a pinhead, that utilize 3-D cone-shaped webs as ultrafast slingshots to capture flying insects. Slingshot spiders are among the very few arachnids known to actively employ a tool (the web) to accelerate 10 times faster than a cheetah. Their legs and claws can withstand forces 100 times greater than their body weight and can initiate the slingshot motion in less than a millisecond. Investigating the anatomy of slingshot spider legs and claws will enable us to identify key design elements for small-scale, rapid-response mechanical systems. Through collaboration between Dr. Symone Alexander and her research team in the Department of Chemical Engineering at Auburn University, and Drs. Hannah Wood and Jonathan Coddington at the Smithsonian Institute National Museum of Natural History (NMNH), engineering and biological approaches will be used to identify, catalog, and connect unique features of slingshot spiders across species. Through this work, we will develop and implement cutting-edge modeling and imaging techniques to create new technology for handling and analyzing delicate or sensitive materials, all inspired by the SS and its unique prey capture strategy.This Research Infrastructure Improvement Track-4 EPSCoR Research Fellows project will provide a fellowship to an Assistant Professor and training for a graduate student at Auburn University. The project will be conducted in collaboration with researchers at the Smithsonian Institute National Museum of Natural History (NMNH). The goals of this work are to: (1) Utilize micro-computed tomography (micro-CT) to identify leg segment morphologies that enable SS to withstand large tensile forces over extended timeframes; (2) Use micro-CT to identify claw morphologies that enable SS to grip/release silk at high speeds; and (3) Compare closely related theridiosomatid species that do and do not use the slingshot motion to understand the evolution of latching morphologies for prey capture. The project will couple these findings with high-speed video data to provide a multiscale, mechanistic understanding of SS prey capture. The host site, NMNH, provides a unique opportunity to compare morphologies of closely related species. The project will significantly advance the exploration of load and release mechanisms of SS by expediting the acquisition of essential cross-cutting expertise in spider morphology and biomechanics. This work will also advance fundamental knowledge by revealing the morphologies necessary to withstand high tension forces and rapidly respond to environmental stimuli. Exploring SS leg morphology, especially the less-studied proximal joints, will lead to the identification of a lightweight, small-scale biomechanical system capable of withstanding large loads with sub-millisecond response times, inspiring the design of new micromechanical systems and responsive actuators. The investigation of claw morphology will uncover design parameters for ultrafast gripping technology that can generate high frictional forces without damaging delicate materials. Additionally, comparative morphology across theridiosomatid species will aid in identifying new species, expanding NMNH collections, and providing new insights into the evolution of SS ultrafast prey capture.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.