DISSERTATION RESEARCH: Burrowing Behavior of Eastern Moles

哺乳动物对地下生活的专门化已经进化了多次，作为觅食、躲避捕食者、储存食物和筑巢的策略；然而，研究人员对挖洞行为知之甚少，因为很难想象动物在土壤中移动。这个项目的重点是东部鼹鼠的挖洞行为，因为它们是专门的挖掘者，已经进化出了极端的形态特殊化，以强大的挖洞，并根据它们遇到的土壤类型表现出两种不同的挖洞行为。本研究将探讨东部鼹鼠如何以及为什么会根据不同密实度的土壤改变它们的挖洞行为。这项工作将把挖洞的形态特化与挖洞行为联系起来，并为更广泛地研究其他鼹鼠和其他哺乳动物的挖洞趋同进化奠定基础。此外，本研究将通过提供对所有学术水平的进化和比较解剖学教学有用的挖掘动画来促进教育，通过提供关键的运动学数据来改进用于城市搜索和救援的鼹鼠启发机器人的设计，从而使公众受益，通过招募当地社区成员来帮助确定鼹鼠的栖息地，最后，将支持这些研究人员继续参与科学咖啡馆项目，该项目为公众举办通俗易懂的科学讲座，聚焦当地科学家。在这项研究中，研究人员打算在初步数据的基础上，通过询问在密实度上不同的土壤中，挖洞行为是如何变化的，以及行为的变化是如何平衡力、速度和用于位移土壤的力的轨迹之间的权衡的。研究人员假设侧向划动和刮削运动涉及不同的关节，使用频率不同，侧向划动在置换松散土壤时更有效，而刮削运动在置换致密土壤时最有效。双平面x射线视频和测力板将用于可视化和量化东方鼹鼠如何改变四肢的运动，以应对在柔软和紧凑的基板上移动的挑战。警力和视频数据将分别通过Dryad.org和XMA门户网站（http://xmaportal.org/webportal/）向公众提供。

Specialization for life underground has evolved multiple times in mammals as a strategy for foraging, avoiding predators, storing food and nesting; however, researchers know very little about burrowing behaviors because it is difficult to visualize animals as they move through soil. This project focuses on burrowing behavior in Eastern moles because they are specialized diggers that have evolved extreme morphological specializations for powerful burrowing and exhibit two different burrowing behaviors in response to the type of soil they encounter. This study will investigate how and why Eastern moles change their burrowing behavior in response to soils of different compactness. This work will connect morphological specializations for burrowing to burrowing performance, and set the stage for broader investigations of the convergent evolution of burrowing in other species of moles and other mammals. In addition, this research will promote education by providing animations of burrowing useful in teaching evolution and comparative anatomy at all academic levels, benefit the general public by providing crucial kinematic data for improving the design of mole-inspired robots that are used in urban search and rescue, engage the public by recruiting local community members to help identify mole habitats, and lastly, will support the researchers continued participation in the Science Cafe program, which hosts accessible scientific talks for the public that spotlight local scientists. In this study, the researchers intend to extend upon preliminary data by asking how burrowing behavior changes in response to soils that differ in compactness and how changes in behavior balance the trade-off between force, speed and the trajectory of force used to displace soils. The researchers hypothesize that lateral stroke and scraping movements involve different joints and are used with different frequencies and that lateral strokes are more efficient in displacing loose soil while scraping movements are most efficient in displacing compact soil. Bi-planar x-ray video and force plates will be used to visualize and quantify how Eastern moles change the movements of their limbs in order to meet the challenges of moving through soft and compact substrates. Force and video data will be made available to the public through Dryad.org and the XMA portal (http://xmaportal.org/webportal/), respectively.