| 英文摘要: | A fundamental goal of biology is to understand the diversity of life. Some of the most interesting diversity involves ecomorphs, which are different species that have evolved to have similar body forms and behaviors that adapt them to the same ecological niche. It is known that the same ecomorph often evolves independently many times, but little is known about what explains overall patterns of ecomorph evolution. For example, is evolutionary change between some ecomorphs more common than others, and what explains these differences? In this project, a new, integrative approach will be developed to explore these fundamental questions about evolution, using frogs as a model system. The approach combines reconstructing species ancestry, (i.e., their evolutionary relationships), with data on species ecology, body morphology, physiological performance (how well they jump, swim, and climb), and their geographic distribution. This study will provide the first exploration of how these different factors explain large-scale patterns of ecomorph evolution across this major group of organisms. To address these factors, the investigators will develop statistical tools that can be applied to any group of organisms. General questions about the methods used to reconstruct evolutionary trees with genetic data will also be addressed. This project will support training of undergraduates, graduate students, and postdoctoral researchers in a diversity of disciplines and techniques. The training will also include a summer undergraduate research experience, with students recruited from historically underrepresented groups. Outreach talks and a video on the project's goals, results, and implications will be delivered to public audiences.
This project has two major objectives. First, a new large-scale phylogeny of anurans will be developed, using new phylogenomic data from ultraconserved elements and existing supermatrices. Urgent and general questions about the methodology of phylogenomic analyses will also be addressed. Second, the investigators will estimate patterns of transitions in ecomorphs and test the factors that explain these patterns. Specifically, researchers will collect morphological data from museum specimens for ~2,500 species. They will also collect new performance data for 65 targeted species from North America, Europe, Africa, and Madagascar, and add this to their existing performance data for 63 species from Asia, Australia, and North and South America. Data will be obtained on microhabitats and analyzed in the context of the new phylogeny to estimate transition rates among microhabitat-associated ecomorphs. Several hypotheses will then be tested about why transition rates differ among ecomorphs, including hypotheses related to ecomorph morphology, functional performance, diversification rates, and biogeography. Data will come from the scientific literature, specimens from scientific collections, and fieldwork in North America, Europe, and Africa. |