IRFP: Testing Hypotheses Regarding Function and Evolution of Placentotrophy, Using Viviparous Skinks as a Model

IRFP：以胎生石龙子为模型，检验有关胎盘功能和进化的假设

• 批准号: 1064803
• 负责人: James Van Dyke
• 金额: $ 15.88万
• 依托单位: VanDyke James U
• 依托单位国家: 美国
• 项目类别: Fellowship Award
• 财政年份: 2012
• 资助国家: 美国
• 起止时间: 2012-06-01 至 2014-06-30
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1064803&HistoricalAwards=false
• 关键词: IRFP; Testing; Hypotheses; Regarding; Function

The International Research Fellowship Program enables U.S. scientists and engineers to conduct nine to twenty-four months of research abroad. The program's awards provide opportunities for joint research, and the use of unique or complementary facilities, expertise and experimental conditions abroad. This award will support a twenty-four-month research fellowship by Dr. James U. Van Dyke to work with Dr. Michael Thompson at the University of Sydney, in Sydney, Australia. Mechanisms of reproductive allocation are the means by which individual animals provision resources to their offspring. These mechanisms may respond to food web disruption and subsequent resource limitation via alterations of either reproductive output, parental survival, or both. Therefore, understanding mechanisms of reproductive allocation is central to understanding population dynamics within the context of global environmental change. Among amniotes, placentotrophic lizards of the family Scincidae are the only taxa to exhibit intermediacy between complete reliance on yolk (lecithotrophy), and complete reliance on placentation (placentotrophy), for embryonic nutrition. As a result, they have long served as the only available models for studies of evolution of placentation in amniotes. However, only recently has our understanding of the diversity of placental morphology and function progressed to the point that questions regarding the evolution of amniote placentotrophy can be addressed. This research makes two major advances to the understanding of amniote placental function and evolution. First, it provides an analysis of how intermediate reliance on both yolk (lecithotrophy) and placenta (placentotrophy) affect reproductive success during periods of food limitation. Second, it utilizes a novel tracer technique to determine which placental tissues are responsible for providing embryonic nutrition in placentotrophic skinks. Together, the results of this project provide novel insights into the placental function of a species that utilizes both lecithotrophy (yolk) and placentotrophy (placenta), which advances understanding of the evolution of placentotrophy from an ancestral lecithotrophic state in vertebrates. By focusing on reproductive responses to food limitation, this research also provides a template for mechanistically predicting population-level responses to global environmental change. Therefore this research directly links studies of placental function with conservation in the face of global environmental change.

国际研究奖学金计划使美国科学家和工程师能够在国外进行9至24个月的研究。该计划的奖项提供了联合研究的机会，以及使用国外独特或互补的设施，专业知识和实验条件。该奖项将支持詹姆斯U博士为期24个月的研究奖学金。货车戴克与迈克尔汤普森博士在悉尼大学，在悉尼，澳大利亚。生殖分配机制是个体动物向后代提供资源的方式。这些机制可能通过改变生殖输出、亲本存活或两者来应对食物网破坏和随后的资源限制。因此，了解生殖分配的机制是理解全球环境变化背景下的人口动态的核心。 在蜥蜴类中，只有蜥蜴科的胎盘营养型蜥蜴在胚胎营养方面表现出完全依赖卵黄（卵磷脂营养）和完全依赖胎盘（胎盘营养）之间的中间状态。因此，它们长期以来一直是唯一可用的模式，用于研究胎盘的进化在Escherotes。然而，直到最近，我们对胎盘形态和功能多样性的理解才进展到可以解决关于胎盘营养进化的问题。 这项研究对了解胎盘的功能和进化有两个重大进展。首先，它提供了一个分析中间依赖蛋黄（lecithotrophy）和胎盘（placentotrophy）影响繁殖成功期间的食物限制。其次，它利用一种新的示踪技术，以确定胎盘组织负责提供胚胎营养的胎盘营养石龙子。总之，该项目的结果提供了新的见解胎盘功能的一个物种，利用lecithotrophy（蛋黄）和胎盘（胎盘），这推进了胎盘营养的进化从祖先lecithotrophy状态的脊椎动物的理解。通过关注食物限制的生殖反应，这项研究还提供了一个模板，用于机械地预测人口水平对全球环境变化的反应。因此，这项研究直接将胎盘功能的研究与面对全球环境变化的保护联系起来。