Phylogeny and Rates of Evolution of the Carnivora (Mammalia)

小行星9707225 食肉目（哺乳动物）是生物学研究的一个极其重要的群体，原因有几个，包括（i）在除南极洲以外的所有陆地上出现，（ii）在各种陆地和水生栖息地中作为关键捕食者的位置，（iii）拥有各种各样的行为（包括社会），喂养和其他（通常是独特的）适应性，以及（iv）广泛的化石记录。 研究人员John Flynn和Michael Nedbal将研究来自化石食肉动物的大量新的，高质量的颅骨和颅后特征，以更好地确定早期食肉动物群体的辐射模式和时间-这将提供一个关键框架，其中现代食肉动物组合之间的多样化和谱系关系。 Flynn和Nedbal还将从大约30个代表性的食肉动物类群中采集并检查大约125，000个碱基对的DNA样本。 DNA序列将来自线粒体编码的两个基因和细胞核编码的两个基因。 DNA序列将提供一个独立的数据源，从其中食肉动物之间的系谱关系将被推断。 最后，Flynn和Nedbal将每个基因序列映射到最支持的系谱上，以测试分子变化的假设。 具体来说，他们将研究分子变化是否在时间上或多或少均匀地发生（“分子钟”理论），或者变化是否是偶发的。 这项研究的结果将对食肉动物和分子多样化的过程和模式产生深远的影响。

9707225 Flynn The Carnivora (Mammalia) are an extremely important group for biological studies for several reasons, including (i) occurrence in all land masses except Antarctica, (ii) position as keystone predators in a variety of terrestrial and aquatic habitats, (iii) possession of a broad variety of well-documented behavioral (including social), feeding, and other (often unique) adaptations, and (iv) an extensive fossil record. Investigators John Flynn and Michael Nedbal will examine a large suite of new, high-quality cranial and postcranial characters from fossil carnivorans to better determine the pattern and timing of radiation in early carnivoran groups - this will provide a critical framework from which diversification and genealogical relationships among modern carnivoran assemblages. Flynn and Nedbal also will acquire and examine about 125,000 base pairs of DNA sampled from roughly 30 representative carnivoran taxa. The DNA sequences will come from two genes encoded by the mitochondria and two genes encoded in the nucleus. The DNA sequences will provide an independent data source from which genealogical relationships among Carnivora will be inferred. Finally, Flynn and Nedbal will map each gene sequence onto the best-supported genealogies in order to test hypotheses of molecular change. Specifically, they will examine the issue of whether molecular change occurs more-or-less homogeneously through time (the "molecular-clock" theory) or whether change is episodic. Results from the study will have far-reaching implications relative to the processes and patterns of carnivoran and molecular diversification.