Biological Consequences of Environmental Change in the Bivalve, Astarte: Relationships Between Lifespan, Growth Rate, and Cold vs. Warm Climate States

环境变化的生物学后果是什么？这项研究的目的是确定区域气候和地理范围大小对一个常见的蛤类物种的壳生长速度和寿命的影响，这些蛤类物种来自沿着美国东南部沿海平原和中北大西洋发现的现代和化石种群。研究中包括的种群将提供对环境变化如何影响生活在不同年温范围地区的双壳类动物寿命的理解。研究成果将增进我们对环境变化对生活在敏感沿海生境中的生物体的影响的认识。我们的方法和结果将有一个显着的教育效益，特别是对学生从代表性不足的群体（例如，第一代对STEM领域感兴趣的大学生），并将通过使用STEM教育机制激励创新，为高中和本科生所用。通过UNC-BEST（科学教学学士学位教育）计划，我们将授予未来的高中地球科学教师进行科学研究的机会，这将为K-12科学课程生成真实的实验室课程。我们将帮助彭德县学校（为低收入和弱势家庭服务）的教师通过“科学写作和写作中的科学”项目（与UNCW的合作项目）将写作与科学发现结合起来，以改善教学。Astarte贝壳特别适合调查环境变化和生物后果之间的联系（例如，寿命和代谢率的变化），因为它们的大小和随时间的地理分布发生变化。我们将重点关注沿着美国大西洋中部和海湾沿岸平原的上新世-更新世沉积物中的大量Astarte种群以及北大西洋的现代种群。主要目标是：1）利用同位素年代学方法，建立现代和化石Astarte不同地理群年生长检查的季节性时间，2）建立地理带与生长率和寿命的关系，3）建立气候状态与生长率和寿命的关系。目标2和3采用冯·贝塔朗菲生长方程及其衍生物（标准生长指数; SGI）来比较现代和化石之间，跨越地理区域，以及寒冷与温暖气候之间的种群的贝壳生长。我们的零假设将使用混合模型ANOVA和PCA检验进行检验。这些检验将确定控制Astarte种群间变异性的主要成分。这项研究提供了一个更好的了解如何地理分布和季节性温度范围的差异可能会影响双壳类的生长和寿命，以及如何改变条件可能会影响未来的人口。

What are the biological consequences of environmental change? The goal of this research is to determine the impact of regional climate and geographic range size on the shell growth rate and lifespan of a common clam species from modern and fossil populations found along the southeastern US coastal plains and Mid-North Atlantic. The populations included in the study will provide an understanding of how environmental change will affect the lifespan of bivalves that live in regions with different annual temperature ranges. Outcomes will advance our knowledge of the effects of environmental change on organisms that live in sensitive coastal habitats. Our methods and results will have a significant educational benefit, especially for students from underrepresented groups (e.g., first-generation college students interested in STEM fields), and will be used by high school and undergraduate students by stimulating innovation using STEM educational mechanisms. Through the UNC-BEST (Baccalaureate Education in Science & Teaching) program, we will award future high-school earth science teachers the opportunity to perform scientific research that will generate authentic laboratory curricula for K-12 science courses. We will help teachers from Pender County Schools (which serves low income and disadvantaged households) to improve instruction by integrating writing with scientific discovery through the "Writing in Science and Science in Writing" program (a collaborative program with UNCW).Astarte shells are uniquely suited to investigate links between environmental change and biological consequences (e.g., changes in lifespan and metabolic rate) because of their change in size and biogeographic distribution through time. We will focus on the abundant populations of Astarte in Plio-Pleistocene deposits along the US Mid-Atlantic and Gulf Coastal Plains and modern populations in the North Atlantic. The main objectives are to: 1) establish the seasonal timing of annual growth checks in different biogeographic populations of modern and fossil Astarte using isotope sclerochronology; 2) establish the relationship between biogeographic zone to growth rate and lifespan; and 3) establish the relationship of climate state to growth rate and lifespan. Objectives 2 and 3 employ the von Bertalanffy growth equation and its derivative (standard growth index; SGI) to compare shell growth of a population between modern and fossil, across biogeographic zones, and between cold vs. warm climates. Our null hypotheses will be tested using a mixed model ANOVA and PCA tests. These tests will determine the principal components controlling variability among Astarte populations. This study provides a greater understanding of how biogeographic distribution and differences in seasonal temperature range may influence bivalve growth and longevity and how changing conditions may affect future populations.