Collaborative Research: Spider Web Vibrations -- Active and Passive Detection

蛛网传播的振动是许多蜘蛛感官信息的主要来源。最著名的是，它们告知蜘蛛被困在网中的猎物的位置;网的振动也传递来自潜在配偶的信号，并提醒蜘蛛注意自己的捕食者的存在。这些捕食者中的一些反过来利用网络振动发送误导性信号，诱使蜘蛛伏击或在其他网络干扰中“隐藏”它们的接近。因此，了解蜘蛛网的几何形状和组成（蜘蛛网是由几种类型的丝编织而成）如何影响这些线索的传递，对于理解蜘蛛的行为和生态学起着重要的作用。生物学家已经通过实验研究了这些现象，例如，测量不同几何形状引起的网络频率响应。尽管这种模型会提供额外的洞察力，但很少有人关注网络振动建模。例如，在频率响应研究中，实验者仅限于使用天然的网络或去除了线的网络，并且无法测试任意改变线图案或类型的影响，这对于理解网页设计至关重要。该项目将通过探索蜘蛛网的设计来填补这一空白，该设计通过新一代生物和人工构建的网络实验支持的弦网络振动的计算模型来实现。拟议的工作的关键更广泛的影响是使复杂的现代振动模型提供给生物学家和其他专业知识不是在动力系统。蜘蛛如何找到猎物是一个引人入胜的故事，将激发K-12学生与物理，数学，生物学和工程学之间的相互作用; PI将开发一个简化的“教学”界面版本，通过俄勒冈州州立大学的中学外展计划和“拓展你的视野，“一个旨在促进中学女生参与STEM领域的组织。特别是PI将调查网络的几何形状和组成如何影响蜘蛛用于定位和识别被困猎物的振动信号的传输。PI将把现代动力系统理论和实验技术应用于生物学研究中公认的需求，并在此过程中扩展对弦网络物理学的理解。与以前的研究相比，在这一领域，拟议的工作将是第一个明确和定量地考虑整个网络的振动能量的途径，寻找非线性效应的振动响应，并通过实验记录在振动网络的点的全运动。这项拟议中的工作也将是第一项定量研究“主动探测”行为的机制的研究，在这种行为中，蜘蛛采摘或摇动其网络以寻找其动态特性的变化，这将表明网络中存在猎物或捕食者动物。

Web-borne vibrations are the main source of many spiders' sensory information. Most famously, they inform spiders of the location of prey trapped in the web; web vibrations also carry signals from potential mates and alert spiders to the presence of their own predators. Some of these predators in turn exploit web vibrations to send misleading signals that trick spiders into ambushes or to "hide" their approach among other web disturbances. Understanding how web geometry and composition (webs are woven from several types of silk) affect transmission of these cues thus plays an important role in understanding spiders' behavior and ecology. Biologists have investigated these phenomena experimentally, for example, measuring web frequency responses resulting from different geometries. Much less attention has been directed to modeling web vibrations, despite the additional insight such models would provide. In the frequency response study, for instance, the experimenters were limited to working with natural webs or those with threads removed, and could not test the effects of arbitrarily altering thread patterns or types, which would be crucial for understanding web design. This project will fill this gap by exploring the design of spider webs through computational models for the vibration of string networks backed up by a new generation of experiments on biological and artificially-constructed webs. The key broader impact of the proposed work is making sophisticated modern vibration models available to biologists and others whose expertise is not in dynamical systems. How spiders find their prey is a compelling story and will inspire K-12 students with the interplay between physics, math, biology, and engineering; the PIs will develop a simplified 'teaching' version of the interface, to be distributed through Oregon State University's middle-school outreach program and the Berkeley Chapter of "Expanding your Horizons," an organization to promote the inclusion of middle school girls in STEM fields.In particular the PI will investigate how a web's geometry and composition affects the transmission of vibratory signals that spiders use to locate and identify trapped prey items. The PI will apply modern dynamical systems theory and experimental techniques to a recognized need in biological study, and in doing so expands understanding of the physics of networks of strings. Compared to previous research in this area, the proposed work will be the first to explicitly and quantitatively consider whole-web vibration energy pathways, look for nonlinear effects in the vibration response, and experimentally record the full motion of points in the vibrating web. The proposed work will also be the first study to quantitatively investigate the mechanics of "active probing" behavior, in which the spider plucks or shakes its web to look for changes in its dynamic properties, which would indicate the presence of a prey or predator animal in the web.