Competitors, Resource Variability, and the Geographic Mosaic of Coevolution for Crossbills and Conifers

生物学的一个基本挑战是了解不同过程产生生物多样性的程度。解释多样化模式的一个最突出的假设是捕食者和猎物之间的军备竞赛。拟议中的研究将确定在何种程度上的交叉bills（Loxia）和针叶树之间的军备竞赛，有助于适应辐射的交叉bills。这些结果将极大地推进我们的理解，社区背景和资源特征如何影响地理镶嵌的共同进化，从而提供进一步的理论进步的动力。以前使用的技术，包括措施的crossbill喂养率和锥测量，将被用来测试预测有关类型的变化锥性状，应该出现的，如果crosbills和松鼠影响锥结构，并测试是否crosbills已经适应在一个互惠的方式改变锥。这些测试的结果将确定（1）资源特性和竞争者类型如何影响交嘴雀和针叶树的地理镶嵌图的形式，以及（2）军备竞赛在多大程度上促成了交嘴雀的适应性辐射

A fundamental challenge of biology is to understand the extent to which different processes generate biological diversity. One of the most prominent hypotheses to explain patterns of diversification is that of an arms race between predators and their prey. The proposed study will determine the extent to which arms races between crossbills (Loxia) and conifers have contributed to the adaptive radiation of crossbills. These results will greatly advance our understanding of how community context and resource characteristics affect the geographic mosaic of coevolution, and thus provide the impetus for further theoretical advances. Previously used techniques, including measures of crossbill feeding rates and cone measurements, will be used to test predictions concerning the types of changes in cone traits that should arise if crossbills and squirrels have influenced cone structure, and to test whether crossbills have adapted in a reciprocal manner to the changed cones. The results of these tests will determine (1) how resource characteristics and competitor type affect the form of the geographic mosaic for crossbills and conifers and (2) to what extent arms races have contributed to the adaptive radiation of crossbills