DISSERTATION RESEARCH: Testing Hypotheses of Morphological Differentiation in the Introduced Lizard, Anolis sagrei

目前物种引进的速度是史无前例的。将新物种引入与其没有共同进化历史的群落，导致引入的物种与其新环境之间以及引进物种与本地物种之间的新的相互作用。这些计划外的实验可能被用来询问有关基本的生态和进化过程的问题。通过对蜥蜴Anolis sgrei的介绍，我们将检验从栖息地利用预测的形态分化的假设，这两个特征在本地种群之间具有良好的生态形态关系。我们将检验这样的假设，即后肢长度和脚趾垫板的数量在根据蜥蜴栖息地的直径和高度预测的方向上存在差异。为了确定引入群体的起源，我们将通过将引入群体中的线粒体DNA单倍型分配给本地范围内支持良好、地理受限的单倍型分支来重建引入的历史。这允许识别引入来源的总体比较以进行假设检验。导言提供了一个检验适应性特征分化假说的绝佳机会。在更广泛的层面上，研究引入种群的分化和进化过程的模式有助于更好地理解生物入侵的原因、进展和预测，生物入侵对生物多样性构成主要威胁。

The current rate of species introductions is unprecedented. Introductions of new species into communities with which they share no recent evolutionary history results in novel interactions between the introduced species and its new environment, and between introduced and native species. These unplanned experiments may be used to ask questions about fundamental ecological and evolutionary processes. Using introductions of the lizard, Anolis sagrei, we will test hypotheses about morphological differentiation predicted from habitat use for two traits with well-supported ecomorphological relationships among native populations. We will test the hypotheses that hindlimb length and toe-pad lamellae number differentiate in the direction predicted from the diameter and height of perches that lizards occupy. To identify the origin of introduced populations, we will reconstruct the history of the introduction by assigning mitochondrial DNA haplotypes from introduced populations to well-supported, geographically circumscribed haplotype clades in the native range. This allows identification of introduced-source population comparisons for hypothesis testing. Introductions present an excellent opportunity to test hypotheses of adaptive trait differentiation. At a broader level, studying patterns of differentiation and evolutionary processes in introduced populations leads to a better understanding of the causes, progression, and prediction of biological invasions, which pose a major threat to biodiversity.