Dissertation Research: Embryonic learning in stickleback: An evolutionary perspective

刺鱼(Gastersteus Aculeatus)是分布广泛的物种，在北半球的海洋和淡水生态系统中占有一席之地。分布广泛的物种在其范围内暴露在不同的环境条件下，包括局部捕食的变化。学习使用周围环境的感官线索可以极大地增强捕食者的躲避能力，并可以进化出对捕食变化的适应。胚胎和幼年刺鱼面临着来自各种捕食者的风险，因此利用环境信号来学习和躲避当地的捕食者可能会受益。嗅觉线索，如捕食者排泄物中释放的气味，提供了关于捕食者饮食的可靠信息，可以很容易地被刺鱼胚胎和鱼苗用来了解捕食者。对刺鱼胚胎和非条件个体孵化后对捕食者气味的反应的检测表明，在实验室条件下，胚胎确实会学习。这种学习对孵化后对捕食者气味的反应有显著影响，并影响随后的学习机会。这项研究的目的是解决在实验室中展示的胚胎学习在性质上是否相关。这项研究的结果具有重要的保护意义，因为学习可能在让猎物识别新威胁方面发挥关键作用。新奇的捕食者(通常是运动鱼)经常被引入到有刺鱼的湖泊中，这对天真的刺鱼构成了更高的风险。该项目已经有几名本科生研究助理参与，并将为更多的研究生(硕士和博士)和本科生提供在实验室和现场获得经验的机会，帮助他们发展自己的研究项目。

The threespine stickleback (Gasterosteus aculeatus) is a widely-distributed species, occupying marine and freshwater ecosystems throughout the northern hemisphere. Widely distributed species are exposed to variable environmental conditions across their ranges, including variation in local predation. Learning to use sensory cues from the surrounding environment can greatly enhance predator avoidance, and can be an evolutionary adaptation to variation in predation. Embryonic and juvenile stickleback are at risk from a variety of predators, and therefore could benefit from use of environmental signals to learn and avoid local predators. Olfactory cues, such as odors released in a predator's waste, provide reliable information about a predator's diet and could be readily used by stickleback embryos and fry to learn predators. Examination of the post-hatching response of stickleback conditioned to predator odors as embryos versus unconditioned individuals demonstrated that under laboratory condition embryos do learn. This learning has a significant effect on post-hatching response to predator odors, as well as affecting subsequent learning opportunities. The aim of this study is to address whether the embryonic learning demonstrated in the laboratory is relevant in nature. The results of this research have important conservation implications, as learning is likely to play a critical role in allowing prey to recognize novel threats. Novel predators (typically sport fish) are regularly introduced to lakes containing stickleback and this poses an elevated risk to predator-naïve stickleback. This project has already involved several undergraduate research assistants, and will provide opportunities for additional graduate (Masters and Doctoral) and undergraduate students to gain experience in the laboratory and field, helping them develop their own research projects.