Collaborative Research: Araneid Phylogeny and Evolution of Spider Silk Phenotypes

蜘蛛产生不同类型的丝，具有显着的物理特性。有些蜘蛛丝甚至可以在断裂前吸收比高性能人造材料更多的能量。圆网是一个杰出的例子，它结合了两种类型的丝纤维的特性，坚硬的支撑线和有弹性的捕获螺旋，起到吸收飞行昆虫猎物的高能量冲击的作用。然而，不同种类的蜘蛛结出的圆网形状却截然不同。该项目旨在了解蜘蛛丝的机械功能如何与不同种类蜘蛛织网方式的变化有关。研究将包括三个步骤。1)它将通过使用新的DNA数据和扩展的形态学数据，为圆织蜘蛛之间的进化关系提出第一个可靠的假设。2)它将测量网的形状，并量化球网的两种组成纤维，框架线和粘性捕获丝的材料特性。这将包括测试由生态多样性的圆织蜘蛛样本纺出的丝纤维的强度、弹性和韧性。3)然后将这两种类型的数据结合起来，研究不同的圆织蜘蛛之间的蛛丝的生物力学特性如何与网络形状共同进化，这些蜘蛛彼此具有相似和非常不同的生态。该项目将产生三个主要的更广泛的影响：1）促进蜘蛛丝的生物技术开发，2）指导科学领域代表性不足的学生，3）促进公众科学素养。蜘蛛丝的极端性能使其成为开发仿生超级纤维和织物的理想模型。这个项目将展示生物勘探者如何利用蜘蛛网的形状作为蜘蛛纺出机械上不寻常的丝的指标。它还将决定丝绸的不同机械性能彼此独立变化的程度。这些知识对于生物工程重组蜘蛛丝的工作至关重要，这些重组蜘蛛丝需要独特的强度和弹性组合。本科生每年将通过自主课题的开发和完成，积极参与本项目的基础科研。这些项目将涉及网络进化和丝绸力学，其中一些学生甚至将参加到非洲和南美洲的实地研究旅行，在那里他们将接触到生物多样性相关的研究和新文化。这是特别相关的，因为U阿克伦学生主要来自人口稠密的东北部俄亥俄州和生物学学生的大多数是女性，与来自代表性不足的少数民族群体超过30%。这些学生中的许多人没有接触过基础科研或科学领域的职业机会。最后，调查人员将利用媒体对蜘蛛网和蜘蛛丝的兴趣，提高公众对生物多样性和经常被误解的进化过程的认识。他们还将利用这项研究，通过在阿克伦大学建立的暑期实习项目，向高中生介绍基础科研与工业之间的关系。

Public abstract Spiders produce different types of silks that have remarkable physical properties. Some spider silk can even absorb more energy before breaking than high performance manmade materials. Orb webs are an outstanding example of how a combination of properties from two types of silk fibers, stiff supporting threads and stretchy capture spirals, function to absorb the high energy impacts of flying insect prey. Yet, orb webs spun by different species of spiders can have radically different shapes. This project seeks to understand how the mechanical function of spider silk may evolve in relation to changes in the way different species of spiders spin webs. The research will involve three steps. 1) It will produce the first robust hypothesis for evolutionary relationships among orb-weaving spiders by using novel DNA data and expanded data on morphology. 2) It will measure the shapes of webs and quantify the material properties for the two constituent fibers of orb webs, frame threads and sticky capture silk. This will include testing the strength, stretchiness, and toughness of the silk fibers spun by an ecologically diverse sampling of orb-weaving spiders. 3) These two types of data will then be combined to examine the how the biomechanical properties of silks coevolve with web shape among different of orb-weaving spiders that have both similar and very different ecologies from one another. This project will have three primary broader impacts; 1) facilitating biotechnological exploitation of spider silks, 2) mentoring of underrepresented students in science, and 3) contributing to public scientific literacy. The extreme performance of spider silk makes it a desirable model for the development of biomimetic superfibers and fabrics. This project will demonstrate how web shape can be used by bioprospectors as an indicator for spiders that spin mechanically unusual silks. It will also determine the degree to which different mechanical properties of silks can change independently of one another. This knowledge is essential for efforts to bioengineer recombinant spider silk for customized applications that require unique combinations of strength and stretchiness. Undergraduates will be actively involved in basic scientific research each year of this project through the development and completion of independent projects. These projects will relate to web evolution and silk mechanics and some of these students will even participate in field research excursions to Africa and South America, where they will gain exposure to biodiversity related research and to new cultures. This is particularly relevant, because U Akron students are predominately from heavily populated northeastern Ohio and a majority of biology students are female, with more than 30% from under-represented minority ethnic groups. Many of these students have not been exposed to basic scientific research or to career possibilities in the sciences. Finally, the investigators will use the media's interest in spider webs and silk to enhance the public's knowledge of biodiversity and the often-misunderstood process of evolution. They will also use the research to introduce high school students to the relationship between basic scientific research and industry through established summer internship programs at U Akron.