Dissertation Research: Using Genealogical Portraits of Speciation to Understand Diversity Patterns

论文研究：利用物种形成的谱系肖像来理解多样性模式

• 批准号: 9801284
• 负责人: Douglas Futuyma
• 金额: $ 0.99万
• 依托单位: SUNY at Stony Brook
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-06-01 至 2000-05-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=9801284&HistoricalAwards=false
• 关键词: Dissertation; Research; Using; Genealogical; Portraits

Futuyma 9801284 The proposed research uses molecular analyses to gain insight into the origin of species in the relatively recent geological past, and into the biological consequences of major changes in climate. The mountains of western North America constitute an unusual archipelago of sky islands for high-altitude species. Closely related species, including Melanoplus grasshoppers as well as other animals and plants, occupy different mountain ranges and peaks, in a pattern that suggests recent evolutionary diversification. It as often been suggested that such species originated by isolation and colonization during the Pleistocene glaciations that ended about 10,000 years ago. However, it is not certain which regions remained free of ice, or how habitats such as grasslands were distributed during the alternating glacial and interglacial periods. Thus the exact history by which organisms came to occupy different mountain ranges and differentiated into distinct species is very uncertain. For instance, species may have colonized progressively more northern areas from southern refuges as the glaciers retreated. Alternatively, ancestral species may have persisted at low altitudes, and have given rise to new species, as their habitats became restricted to isolated mountaintops when the climate became warmer. The proposed research uses Melanoplus grasshoppers to determine more fully the history by which biodiversity has originated in the western mountains. Comparisons of DNA sequences among populations and species from different mountain ranges can provide dates for divergence, and thus test the hypothesis that many species formed during or since the Pleistocene glaciations. Evolutionary relationships among species as reconstructed from DNA sequences, will be used to determine whether species formed by fragmentation or by progressive northward colonization. This research will provide one of the few comprehensive views of an evolutionary radiation. Using modern phylogenetic techniques and population genetic models, it will test hypotheses about species formation, and thus provide insights into the origin of diversity. And it will cast light on how past changes in climate have affected the distribution and diversity of organisms - information that may help to predict effects of future global changes in climate.

Futuyma 9801284拟议的研究使用分子分析来深入了解物种在相对较新的地质过去，以及气候重大变化的生物学后果。 北美西部的山构成了高海拔物种的天空岛的一个不寻常的群岛。 密切相关的物种，包括黑色素鳞茎以及其他动物和植物，占据了不同的山脉和峰，这种模式表明最近进化多样化。 经常提出，这种物种起源于大约10，000年前的更新世冰川期间的分离和定殖。但是，不确定哪些区域仍然没有冰，或者在交替的冰川和冰川间期间如何分布草地等栖息地。 因此，生物体占据不同的山脉并分化为不同物种的确切历史非常不确定。 例如，随着冰川的撤退，物种可能逐渐从南部避难所殖民。 另外，祖先物种可能一直持续到低海拔，并引起了新物种，因为当气候变暖时，它们的栖息地仅限于孤立的山顶。 拟议中的研究使用黑色素晶状体蚱hoppers来更充分地确定生物多样性起源于西部山区的历史。 来自不同山区范围的人群和物种之间的DNA序列的比较可以提供分歧的日期，从而检验了许多在更新世冰川期间形成或以来许多物种形成的假设。 从DNA序列重建的物种之间的进化关系将用于确定是由碎片化或渐进的北向定植形成的物种。这项研究将提供进化辐射的少数全面观点之一。 使用现代的系统发育技术和人群遗传模型，它将检验有关物种形成的假设，从而提供对多样性起源的见解。 它将阐明气候的过去变化如何影响生物的分布和多样性，这些信息可能有助于预测未来全球气候变化的影响。