SG: Distinguishing between core and transient species: new insights into the determinants of species richness

了解生物多样性在全球范围内如何变化以及为什么变化是生态学长期关注的问题，也是许多保护努力的根本关切。然而，简单地统计一个地区的物种数量可能不能准确地表示生物多样性，因为在一个地区观察到的许多物种并不经常出现在那里。通过分析北美近500个地点的志愿观鸟者在过去40年中收集的数据，发现大多数鸟类可分为两类：几乎每年都在一个地点观察到的核心物种，以及很少被观察到的临时物种。核心鸟类的数量与当地气候和植被的相关性最大，而过渡鸟类的数量在生境多样性的地区最多，与气候无关。该项目将评估核心物种和临时物种之间这种区别的普遍性，以及这种区别对于了解包括鸟类、哺乳动物、蝴蝶、植物、鱼类、浮游生物和潮间带无脊椎动物在内的广泛分类群体和生态系统的物种多样性模式的重要性。这项研究的结果将对对生物多样性决定因素的基本和应用理解以及生态社区如何应对气候和土地利用变化产生影响。将为一名研究生提供研究培训和职业指导。将与北卡罗来纳大学数学与科学教育中心和大学预科项目一起，开展面向中学生的公共宣传活动，其中包括来自代表不足群体的大部分学生。大学预科方案是一个以探究为基础的方案，旨在丰富和鼓励妇女和在科学和数学事业中代表性不足的少数群体在科学和数学方面的知识。这一推广活动的一个产品将是在北卡罗来纳州植物园展出的解释性展示。研究人员还将提供有组织的讲习班，以提高各级科学家的计算和数据管理技能。

Understanding how and why biodiversity varies across the globe is a long-standing focus of ecology and is a fundamental concern of many conservation efforts. However, simply counting the number of species in an area may not give an accurate representation of biodiversity because many of the species observed in an area do not occur there regularly. By analyzing data collected over the past forty years by volunteer birders at almost 500 locations across North America, it was found that most bird species fall into one of two categories: core species that are observed almost every year at a site, and transient species that are observed only rarely. The number of core bird species was most strongly related to local climate and vegetation, whereas the number of transient bird species was greatest in regions with a diversity of habitats, independent of climate. This project will assess the generality of this distinction between core and transient species, and the importance of that distinction for understanding patterns in species diversity across a broad range of taxonomic groups and ecosystems including birds, mammals, butterflies, plants, fish, plankton, and intertidal invertebrates. Results from this research will have implications for both basic and applied understanding of the determinants of biodiversity, and for how ecological communities will respond to climate and land use change. Research training and career mentoring will be provided for one graduate student. In conjunction with the University of North Carolina's Center for Mathematics and Science Education and the Pre-College Program, public outreach activities will be developed that engage middle school students, including a large proportion from underrepresented groups. The Pre-College Program is an inquiry-based program of enrichment and encouragement in science and mathematics for women and minorities underrepresented in scientific and mathematical careers. One product of this outreach will be an interpretive display exhibited at the North Carolina Botanical Garden. The researchers will also provide structured workshops to improve the computational and data management skills of scientists of all levels.