CAREER:Ecological Diversification of Marine Mammals (Orders Cetacea and Sirenia) through Cenozoic Climate Change: Evidence from Geochemical Analysis of Fossil Material

职业：新生代气候变化导致海洋哺乳动物（鲸目和海牛目）的生态多样化：来自化石材料地球化学分析的证据

• 批准号: 0847413
• 负责人: Mark Clementz
• 金额: $ 54.18万
• 依托单位: University of Wyoming
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-04-01 至 2015-03-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0847413&HistoricalAwards=false
• 关键词: CAREER; Ecological; Diversification; Marine; Mammals

CAREER:Ecological Diversification of Marine Mammals (Orders Cetacea and Sirenia) through Cenozoic Climate Change: Evidence from Geochemical Analysis of Fossil MaterialMark T. Clementz, Department of Geology & Geophysics, University of Wyoming Cetaceans (e.g., whales, dolphins, porpoises) and sirenians (e.g., sea cows: manatees, dugongs) are major consumers in nearshore and offshore foodwebs and play a strong part in regulating the structure and composition of these communities today. Their earliest influence on aquatic ecosystems occurred at 50 Ma, when the first whales and sea cows appeared in the fossil record. Both geochemical and morphological evidence suggest that these groups already had a strong affinity for life in the water. New discoveries of members of each order in India and Pakistan at or shortly after this event have led to a significant accumulation of fossil material documenting most of the critical steps within the transition from terrestrial to marine ecosystems by whales and sea cows. This wealth of collected material makes it now possible to examine the evolution of these groups in a more rigorous, quantitative manner. This, in turn, can provide new insights into the relationship between ecological change and morphological evolution for these groups. The primary goal of this project is to compare the evolutionary ecology of these two groups of marine mammals (Orders Cetacea and Sirenia) in the context of environmental conditions and Cenozoic climate change. With the appearance of whales and sea cows in the Early Eocene, the evolution and diversification of both groups occurred across major episodes of significant climate change as the Earth moved from the greenhouse conditions of the early Paleogene and into the icehouse conditions of the Neogene and today. In order to effectively evaluate the impact that this climate change may have had on the evolution of each, I plan to examine specimens of whales and sea cows as components of marine food webs. This requires that I not just understand the diet or trophic position of individuals or species, but of entire, coeval marine communities. Key localities representing well preserved marine vertebrate fossil accumulations (i.e., ?bone beds?) have been identified from Eocene, Oligocene and Miocene deposits in the USA (California, Oregon, South Carolina), Egypt and New Zealand for inclusion in this study. I will primarily rely on geochemical analysis of fossil tooth enamel as a proxy for ecological information. This approach involves the analysis of the stable isotopes of calcium, carbon, oxygen, and strontium to define the trophic position, diet, and salinity tolerances, respectively, of each individual examined under this project. Thus, my research component will focus on reconstructing marine food webs from these time periods as well as defining the role of whales and sea cows within them. At the same time, my teaching component will also emphasize an integrative, big-picture approach to educate K-12 and college students on the concepts of evolution, ecology and climate change. This will be done through a combined effort of research in the field and lab and classroom activities, including theater education, to provide students with multiple methods of mental stimulation and assessment. These efforts will be achieved by incorporating these teaching activities and lessons into the current UWyo paleo research program, which will be possible through the assistance of post-doctoral fellows, graduate students, undergraduates, and high school interns funded through this proposal and other sources available at UWyo. The combined research and teaching efforts are intended to provide an opportunity for students to gain a greater appreciation for scientific thinking as well as a better understanding of the processes shaping the natural world around them.

mark T. Clementz，怀俄明大学地质与地球物理系鲸目动物（如鲸鱼、海豚、鼠海豚）和海鲸目动物（如海牛、海牛、儒艮）是近岸和近海食物网的主要消费者，在调节这些群落的结构和组成方面发挥着重要作用。它们对水生生态系统的最早影响发生在50年前，当时化石记录中出现了第一批鲸鱼和海牛。地球化学和形态证据都表明，这些群体已经对水中的生命有很强的亲和力。在这一事件发生时或之后不久，在印度和巴基斯坦发现了每个目的新成员，这导致了大量化石材料的积累，记录了鲸鱼和海牛从陆地生态系统过渡到海洋生态系统的大多数关键步骤。这些收集到的丰富材料使我们现在能够以一种更严格、更定量的方式来研究这些群体的演变。反过来，这可以为这些群体的生态变化和形态进化之间的关系提供新的见解。本项目的主要目的是比较这两类海洋哺乳动物（鲸目和鲸目）在环境条件和新生代气候变化背景下的进化生态学。随着始新世早期鲸鱼和海牛的出现，这两个种群的进化和多样化发生在重大气候变化的主要时期，即地球从古近纪早期的温室环境进入新近纪和今天的冰窖环境。为了有效地评估这种气候变化可能对每种生物的进化产生的影响，我计划研究鲸鱼和海牛的标本，作为海洋食物网的组成部分。这要求我不仅要了解个体或物种的饮食或营养状况，还要了解整个同时期的海洋群落。保存完好的海洋脊椎动物化石聚集的重要地点(例如？在美国（加利福尼亚、俄勒冈、南卡罗莱纳）、埃及和新西兰的始新世、渐新世和中新世矿床中发现了骨床。我将主要依靠牙釉质化石的地球化学分析作为生态信息的代理。该方法包括对钙、碳、氧和锶的稳定同位素进行分析，以确定本项目所检查的每个个体的营养地位、饮食和盐度耐受性。因此，我的研究部分将侧重于重建这些时期的海洋食物网，以及定义鲸鱼和海牛在其中的作用。与此同时，我的教学部分也将强调一种综合的、宏观的方法来教育K-12和大学生关于进化、生态和气候变化的概念。这将通过实地研究、实验室和课堂活动（包括戏剧教育）的共同努力来实现，为学生提供多种精神刺激和评估方法。这些努力将通过将这些教学活动和课程纳入当前的UWyo古研究计划来实现，这将通过博士后研究员，研究生，本科生和高中实习生的帮助来实现，这些资助来自该提案和UWyo其他可用资源。研究和教学相结合的努力旨在为学生提供一个机会，以获得对科学思维的更多欣赏，以及更好地理解塑造他们周围自然世界的过程。