Collaborative Research: Sensory Reception and Predator Evasion in Crustacean Zooplankton: Suppliment to OCE 9910608-"Escape responses of copepods stimulated by an ambush predator

研究人员评估了神经运动过程在蜥蜴类桡足类逃避捕食者中的作用。这些桡足类动物是地球上数量较多的动物之一，数量甚至超过了昆虫。尽管它们对海洋生态系统很重要，但对于这些动物是如何生存的，甚至在充满捕食者的海洋中茁壮成长，人们缺乏关键的理解。例如，研究人员正在研究迅速而有力的逃逸行为，在这种行为中，桡足类似乎会瞬间从接近的捕食者手中‘跳’开。他们假设，逃逸行为在不同物种之间表现出明显的差异，反映了生活在海洋不同环境中的动物的生存策略的差异。在电子显微镜的帮助下，由微小的水运动引发的逃逸的生理和行为特征的差异与神经系统的结构特征相关联。研究人员特别感兴趣的是“髓鞘”的存在或不存在，髓鞘是神经细胞周围的一种保护性鞘。髓磷脂加快神经冲动传导，从而缩短反应时间。桡足类神经系统的特性也与对水运动的敏感度、对光线强度变化的敏感度(模仿捕食者的阴影)、反应时间、附肢的运动、能量产生、反应持续时间、游泳速度和逃逸距离有关。总而言之，研究人员正在提供关于桡足类神经系统不同寻常的感觉和生理能力的定量信息。

Researchers evaluate the role of neuromotor processes in predator-evasion by calanoid copepods. These copepods are among the more numerous animals on earth, outnumbering even insects. Despite their importance to oceanic ecosystems, critical understanding is missing on how these animals survive and, indeed, thrive in an ocean full of predators. Investigators are examining, for instance, the rapid, forceful escape behavior in which copepods seem to 'jump' instantaneously away from an approaching predator. They hypothesize that escape behavior exhibits distinctive variations among species, reflecting differences in survival strategies for animals inhabiting different environments in the ocean. Differences in physiological and behavioral characteristics of escape triggered by minute water movements are being correlated with structural features seen in the nervious system, aided by an electron microscope. Investigators are particularly interested in the presence or absence of "myelin," a protective sheathing around nerve cells. Myelin speeds nerve impulse conduction, thus shortening reaction times. Properties of the copepods' nervous systems are being related, too, to sensitivity to water movement, sensitivity to changes in light intensity (mimicking the shadow of a predator), reaction time, movement of appendages, energy production, response duration, swim speed and escape distance. In sum, researchers are providing quantitative information on the copepod's nervous system's unusual sensory and physiological capabilities.