DISSERTATION RESEARCH: The adaptive significance of shell color variation in the flat periwinkle Littorina obtusata

海洋蜗牛Littorina obtusata以壳色的显著多样性而闻名。贝壳颜色会影响可见光的吸收，进而影响体温和健康。以前的结果表明，在缅因州海湾的壳色多样性的模式是由热制度的变化。在缅因州海湾较热、暴露较多的栖息地，较浅的贝壳颜色的频率增加，而在较冷的地区，深色的贝壳占主导地位。此外，操纵实验表明，在炎热，干燥的条件下，浅壳蜗牛是在一个健身优势。这项研究将进一步测试壳色和适合度之间的关系，检查冷胁迫下的生长和死亡率以及对热胁迫的行为反应。拟议中的研究将提供一个令人信服的例子，在自然种群的选择力的重要性变化的热制度。这样的例子是罕见的，特别是在具有重要生态意义的自然系统中。此外，了解生物体如何应对和适应可变的热状况可能会产生具体的预测，哪些种群和物种最容易受到环境变化的影响，并更好地为保护重要生态系统的方法提供信息。监测了褐飞虱壳色频率的分布。obtusata可能被证明是一种成本效益高、易于处理的方法，用于跟踪气候变化对生态群落的影响。

The marine snail Littorina obtusata is noted for remarkable diversity in shell color. Shell color is expected to affect absorption of visible light that may in turn impact body temperature and fitness. Previous results suggest that patterns of shell color diversity in the Gulf of Maine are driven by variation in thermal regime. Lighter shell colors increase in frequency in hotter, more exposed habitats in the Gulf of Maine whereas dark colors dominate populations in cooler areas. In addition, manipulative experiments demonstrated that light shell colored snails are at a fitness advantage under hot, dry conditions. The proposed study will further test the relationship between shell color and fitness, examining growth and mortality rates under cold stress and behavioral responses to thermal stress in the field. The proposed study will provide a compelling example of the importance of variation in thermal regime as a selective force in natural populations. Such examples are rare, particularly in natural systems with significant ecological relevance. Further, understanding how organisms respond and adapt to variable thermal regimes may generate concrete predictions as to which populations and species are most vulnerable to environmental change and better inform the methods used to protect important ecosystems. Monitoring the distribution of shell color frequencies in L. obtusata may prove to be a cost-effective, tractable method for tracking the effects of climate change in ecological communities.