Collaborative Research: Testing species limits, phylogeographic concordance, and niche evolution in Madagascar's endemic small mammals

理论预测，地理上复杂的地区应该拥有特殊的生物多样性，过去的地球历史事件，如气候波动，将影响遗传变异的多样性和维持。马达加斯加岛就是这样一个复杂的地区。马达加斯加岛上只有四种本土陆生哺乳动物；每一种都曾一度在马达加斯加定居，然后多样化，呈现出惊人的形态和生态变化。这一建议的重点是小型食虫哺乳动物，特别是那些分布在马达加斯加山区潮湿森林带的物种。该项目将使用来自多个基因的DNA序列来确定每个物种中存在多少种遗传上不同的种群，并提供它们分化的时间估计。这组科学家将使用地理信息系统（GIS）利用气候数据集对每个物种的生态位进行建模，以估计物种目前的分布范围，并重建它们在过去冰川周期中的分布。了解形成区域生物多样性的力量是现代生物学的关键目标之一。这个项目将阐明过去的气候事件对塑造当今生物多样性模式的重要性。它将揭示马达加斯加潮湿森林中小型哺乳动物多样性的程度，并确定含有意想不到的遗传变异的区域，为在世界上的一个地区设计保护区和保护策略提供关键信息。美国最重要的生物多样性热点。研究人员将对本科生和研究生进行DNA测序、分析和地理信息系统方面的培训，其中包括来自科学界代表性不足群体的学生。

Theory predicts that geographically complex regions should harbor exceptional biological diversity, and that past Earth history events such as climatic fluctuations will affect the diversification and maintenance of genetic variation. The island of Madagascar represents one such complex region. Only four groups of native terrestrial mammals exist on Madagascar; each colonized Madagascar a single time and then diversified to exhibit spectacular morphological and ecological variation. This proposal focuses on the small insectivore-like mammals, especially on those species distributed throughout Madagascar's mountainous, humid-forest belt. The project will use DNA sequences from multiple genes to determine how many genetically distinct sets of populations exist within each species, and to provide an estimate of how long ago they diverged. The researchers will use Geographic Information Systems (GIS) to model the niche of each species using climatic data sets to estimate the species' current ranges and to reconstruct their distributions during past glacial cycles.Understanding the forces that shape regional biodiversity is one of the key goals of modern biology. This project will illuminate the importance of past climatic events in shaping present-day patterns of biodiversity. It will reveal the extent of small-mammal diversity in Madagascar's humid forests and identify areas containing unexpected genetic variation, providing critical information for designing protected areas and conservation strategies in one of the world?s foremost biodiversity hotspots. The researchers will train undergraduate and graduate students in DNA sequencing and analysis and GIS, including students from groups underrepresented in science.