NSFDEB-NERC Origins and expansion of endemic biodiversity in western Melanesia and their relation to tectonic evolution

西美拉尼西亚-包括新几内亚-位于亚洲和澳大利亚的十字路口，是地球上最有趣、最令人困惑、最未被研究的超多样化地区之一。弄清过去数百万年来构造运动是如何撕裂或连接不同的美拉尼西亚地貌，是了解这种生物多样性的起源的关键。该项目的目的是阐明组成西美拉尼西亚大部分地区的五种主要地质地貌的多样性和演化史如何影响该地区生物群的演化，并确定对殖民和辐射到新几内亚、澳大利亚和/或亚洲岛屿的宗族起源至关重要的那些古老的岛屿大陆。为了实现这一目标，我们将在西美拉尼西亚五大洲具有不同扩散能力、起源时间和自然历史的众多爬行动物和两栖动物(两栖动物)谱系上构建过时的系统发育树。我们将使用恢复的日期和关系来确定每个支系的原产地和时间，并追踪它们向新地区的扩展。这些结果与更新的地质模型之间的交叉验证将阐明推动该地区物种形成和扩散的构造事件。我们使用两栖动物来解决这些问题，因为它们可变但中等的跨海扩散能力使它们比具有更大(例如鸟类)或更小(例如陆地蜗牛)扩散能力的分类群更好地追踪地质历史。这项研究将有助于用更具活力和细致入微的理解来取代过时的、单向的“新几内亚以外”太平洋生物多样性起源模式，即美拉尼西亚古老但被低估的陆地地区长期以来在塑造更广泛区域的生物进化方面发挥着重要作用。

Western Melanesia-including New Guinea-sits at the crossroads of Asia and Australia and is one of the most interesting, puzzling, and understudied hyperdiverse regions on Earth. Clarifying how tectonic movements have sundered or joined different Melanesian landforms in the past several million years is key to understanding the origins of this biotic diversity. The intent of this project is to elucidate how the diversity and evolutionary history of the five major geological landforms that comprise most of western Melanesia have impacted evolution of that region's biota and to identify those ancient insular landmasses critical in the origin of lineages that colonised and radiated across New Guinea, Australia, and/or insular Asia. To meet this goal, we will construct dated phylogenetic trees on a multitude of reptile and amphibian (herpetofauna) lineages having different dispersal abilities, times of origin, and natural histories that span the five major landmasses of western Melanesia. We will use the dates and relationships recovered to identify areas and times of origin for each clade and trace their expansion to new regions. Cross-validation between these results and updated geological models will illuminate tectonic events that drove speciation and dispersal in the region. We use herpetofauna to address these questions because their variable but moderate trans-marine dispersal abilities allow them to better track geological history than do taxa having much greater (e.g., birds) or lesser (e.g., land snails) dispersal capabilities. This research will help to replace the outdated, unidirectional "out-of-New-Guinea" model for origins of Pacific biodiversity with a more dynamic and nuanced understanding that ancient, yet under-appreciated, land areas in Melanesia have long been important in shaping biotic evolution in the broader region.