COLLABORATIVE RESEARCH: Palebiology of Latitudinal Turnover Gradients -- Transoceanic Comparative Analyses

9905379瓦伦丁垂直多样性梯度形成了海洋和陆地系统共享的最引人注目和最普遍的生物多样性模式之一。 然而，这种梯度背后的进化动力是非常有争议的，部分原因是缺乏经验数据。我们建议进行比较分析的物种水平的进化动力学的基础上，海洋纬度多样性的趋势，使用东太平洋，日本和库页岛新近纪软体动物群（0 - ca。1500万年前）。我们将量化物种的起源和灭绝率纬度排列的生物省份沿着每个海岸使用Lyellian的寿命，“向后生存曲线”，和地层的物种持续时间。此外，我们将研究如何在身体大小和生活习性属性的变化，无论是内部和分支之间，影响进化速率和物种的持续时间。我们将利用东太平洋和西太平洋动物群作为平行的自然实验，以检验关于多样性控制和生物模式沿着纬度的组织的假设。这种比较方法将使我们能够考虑地质历史、地理和其他相关变量的区域影响，并检验我们结果的普遍性。

9905379ValentineLatitudinal diversity gradients form one of the most dramatic and pervasive biodiversity patterns shared by both marine and terrestrial systems. However, the evolutionary dynamics underlying such gradients are highly controversial, in part because of the lack of empirical data. We propose to undertake comparative analyses of the species-level evolutionary dynamics that underlie marine latitudinal diversity trends using Eastern Pacific, Japanese, and Sakhalin Neogene molluscan faunas (0 - ca. 15 million years ago). We will quantify species origination and extinction rates for latitudinally arrayed biotic provinces along each coast using Lyellian Percentages, "backwards survivorship curves", and stratigraphic durations of species. In addition, we will investigate how variations in body size and life-habit attributes, both within and among clades, influence evolutionary rates and species durations. We will use the Eastern and western Pacific faunas as parallel natural experiments for testing hypotheses on diversity controls and the organization of biotic patterns along latitude. This comparative approach will allow us to factor out the regional effects of geological history, geography and other relevant variables, and to test for the generality of our results.