DISSERTATION RESEARCH: Life at the ocean surface: evolution and morphology of the Portuguese man of war

葡萄牙军舰Physalia physalis在海面上漂流。它在这种环境中是高度专业化的，用一个充满气体的浮子作为帆来捕捉风，用长长的触手作为钓线来捕捉小鱼和甲壳类动物。许多海滩游客都知道Physalia physalis的疼痛刺，但尽管熟悉和丰富，对这个物种的最基本特征知之甚少。在这个项目中，研究人员将使用新的显微镜技术来回答关于这个独特物种的解剖学、发育和进化起源的老问题。这项研究的成果将通过开放获取出版的方式免费提供给公众和其他科学家。该奖项还将支持当地一所小学有关该项目主题的课程，包括海洋区域、浮游生物、浮游生物和海洋无脊椎动物身体计划的课程。Physalia physalis是唯一的隔水（生活在水和空气之间的界面）的虹吸生物（刺胞纲：水螅纲）。管水母是一种群居动物，由类动物（身体）组成，每个类动物都与独居动物同源。该项目将描述physalis形态的基本特征，并使用系统发育比较方法来重建与从浮游生活方式到平生生活方式过渡相关的进化变化。这项工作的主要成果将是对physalis的重新描述，这也旨在解决以下一些问题：在physalis中动物是如何组织的？physalis的动物形态和群体组织与其他虹吸虫物种有何不同，这对它们的进化有何启示？Physalia physalis菌落具有高度三维的分支结构。光学投影断层扫描，以及其他免疫荧光成像方法，将用于3d成像固定的physalis组织。这些形态学描述将与浮游虹吸水母的形态学描述进行比较，以便研究虹吸水母系统发育中特征进化的一般模式。

The Portuguese man-of-war, Physalia physalis, drifts at the ocean surface. It is highly specialized for this environment using a gas-filled float as a sail to catch the wind and long tentacles as fishing line to capture small fishes and crustaceans. Physalia physalis is known to many beach goers for its painful sting, but despite being familiar and abundant, little is known about most basic features of this species. In this project, researchers will use new microscopy techniques to answer old questions about the anatomy, development, and evolutionary origins of this unique species. The products of this study will be made freely accessible to the public and other scientists via open access publishing. The award will also support lessons in a local elementary school on topics related to this project, including lessons on ocean zones, plankton, pleuston, and marine invertebrate body plans.Physalia physalis is the only siphonophore (Cnidaria: Hydrozoa) that is pleustonic (living at the interface between water and air). Siphonophores are colonial animals that are composed of zooids (bodies) that are each homologous to solitary animals. This project will describe fundamental features of P. physalis morphology and use phylogenetic comparative methods to reconstruct the evolutionary changes associated with a transition from a planktonic to pleustonic lifestyle. The primary product of this work will be a re-description of P. physalis, which also aims to address some of the following questions: how are zooids organized in P. physalis? How does P. physalis zooid morphology and colony organization differ from other siphonophore species, and what does this suggest about their evolution? Physalia physalis colonies have highly 3-dimensional branching structures. Optical Projection Tomography, as well as other immuno-fluorescent imaging methods, will be used to 3D-image fixed P. physalis tissue. These morphological descriptions will be compared with morphological descriptions available for planktonic siphonophores in order to investigate general patterns of character evolution within the siphonophore phylogeny.