Life and Death in Moving Fluids: Hydrodynamic Effects on Chemosensory‐Mediated Predation
Life and Death in Moving Fluids: Hydrodynamic Effects on Chemosensory‐Mediated Predation
复制标题
移动流体中的生与死：流体动力学对化学感应介导的捕食的影响
DOI：
10.2307/1940072
复制
发表时间：
1993
期刊：
影响因子：
4.8
通讯作者：
R. K. Zimmer
中科院分区：
文献类型：
--
作者：
M. Weissburg;R. K. Zimmer
先前对海洋动物分类多样性的研究已经确立了嗅觉在各种行为过程中的普遍存在和重要性。有证据表明，嗅觉对许多海洋动物的掠食性搜索起着调节作用。然而，过去的研究并没有将嗅觉介导的搜索或引导机制的成功程度与自然发生捕食活动的水力环境联系起来。为了研究水动力和化学接受之间的相互作用，我们研究了蓝蟹在水槽中产生的受控水动力环境中的捕食成功率和觅食策略。流体力学通过量化边界层剪切速度（u*）和粗糙度雷诺数（Re.）来表征，这两个指标描述了边界层流动的结构。流动特性影响螃蟹对主动抽吸水生双壳类（雇佣兵）散发的气味羽状物的定位能力。流速大或泥沙粒径大会增加边界层湍流，从而降低蟹类化学定向能力的成功率。此外，高流速也减少了螃蟹接触气味羽流的可能性。因此，高流量的栖息地可以为嗅觉介导的捕食提供水动力避难所。由于搜索能力取决于边界层湍流的大小，如果底部粗糙度元素能够产生足够的湍流，嗅觉介导的捕食在缓慢流动中也可能无效。此外，蓝蟹的搜索能力对底栖边界层结构的微小变化极为敏感。由准层流主导的厚粘性亚层的存在，似乎对螃蟹成功定位气味源尤为关键。底栖河口甲壳类动物生活在一个流动在平滑和粗糙湍流之间过渡的环境中。因此，化学感觉系统似乎主要用于从水力平滑流动中提取信息。这些结果表明，控制气味信号物理传输的机制不仅对感觉和行为机制的发展有深远的影响，而且对生物相互作用（如捕食）也有深远的影响，而这些相互作用又可以调节群落结构。
Previous studies in taxonomically diverse marine animals have established the general existence, and importance, of the olfactory sense in a wide variety of behavioral processes. Evidence suggests that the sense of smell mediates predatory search in many marine animals. Past investigations have not, however, been designed to link either the degree of successful olfactory-mediated search or guidance mechanisms with the hydraulic environment in which predatory activities naturally take place. In an effort to examine the interaction between hydrodynamics and chemoreception, we investigated predatory success and search strategies of blue crabs foraging in controlled hydrodynamic environments generated in a flume. Hydrodynamics were characterized by quantifying boundary layer shear velocity (u*) and roughness Reynolds number (Re.), two measures that describe the structure of boundary layer flows. Flow properties affected the ability of crabs to orient to odor plumes emanating from actively pumping infaunal bivalves (Mercenaria mercenaria). High flow speed or large sediment particle size increased boundary layer turbulence, thereby decreasing the success of crab chemo-orientation ability. In addition, high flow speed also lessened the probability that crabs contacted odor plumes. Thus, habitats with high flows can provide hydrodynamic refuges from olfactory-mediated predation. Because search ability is contingent on the magnitude of boundary layer turbulence, olfactory-mediated predation may also be ineffective in slow flows, if bottom roughness elements can generate sufficient turbulence. Further, search ability in blue crabs is extremely sensitive to small changes in benthic boundary layer structure. The presence of a thick viscous sublayer, dominated by quasilaminar flow, seems especially critical for successful location of an odor source by crabs. Benthic estuarine crustaceans inhabit an environment where flows are transitional between smooth- and rough-turbulent conditions. Accordingly, chemosensory systems appear geared primarily to extracting information from hydraulically smooth flows. These results indicate that mechanisms governing the physical transport of odor signals can have profound influences, not only on the development of sensory and behavioral mechanisms, but also on biotic interactions such as predation, which, in turn, can mediate community structure.