Ferrer Ryan P, Zimmer Richard K
Department of Biology, Seattle Pacific University, Seattle, Washington 98119, USA.
Ann N Y Acad Sci. 2009 Jul;1170:450-5. doi: 10.1111/j.1749-6632.2009.03908.x.
Chemical neuroecology examines the relationships between chemosensory physiology, behavior, and population and community dynamics. A keystone species, for example, is one whose impact on communities is far greater than would be predicted from its relative abundance and biomass. Neurotoxins, then, could function in keystone roles. Rare within natural habitats, they exert strong effects on species interactions at multiple trophic levels. Effects of two guanidine alkaloids, tetrodotoxin (TTX) and saxitoxin (STX), coalesce neurobiological and ecological perspectives. These potent neurotoxins function as chemical defenses by binding to voltage-gated sodium channels on nerve and muscle cells. When borrowed by resistant consumer species, however, they are used in chemical defense against higher-order predators or as chemosensory excitants in mediating critical behavioral interactions. Through a combination of diverse physiological traits, TTX and STX exert profound impacts reverberating across multiple trophic levels and determining a wide range of community-wide attributes. Such traits ultimately render TTX and STX fully functional as keystone molecules, with vast ecological consequences for species assemblages and rates of material exchange.
化学生态神经学研究化学感觉生理学、行为以及种群和群落动态之间的关系。例如，关键物种是指其对群落的影响远远大于根据其相对丰度和生物量所预测的物种。那么，神经毒素可能发挥关键作用。它们在自然栖息地中很罕见，但对多个营养级的物种相互作用有着强烈影响。两种胍生物碱——河豚毒素（TTX）和石房蛤毒素（STX）的作用，融合了神经生物学和生态学观点。这些强效神经毒素通过与神经和肌肉细胞上的电压门控钠通道结合来发挥化学防御作用。然而，当抗性消费物种利用它们时，它们则用于抵御高阶捕食者的化学防御，或作为化学感觉兴奋剂来介导关键的行为相互作用。通过多种生理特性的组合，TTX和STX产生深远影响，在多个营养级间回荡，并决定了一系列广泛的群落属性。这些特性最终使TTX和STX作为关键分子充分发挥作用，对物种组合和物质交换速率产生巨大的生态影响。
