探讨生物对局域环境生态适应的潜在机制是进化生物学的核心任务之一。申请人拟用我国特有的青海沙蜥种组三种蜥蜴，通过假设检验的研究方法探讨4个问题：（1）适合度相关的表型是否因具有谱系独立性而更多地与物种的地理分布和局域环境条件有关？（2）野外种群遗传多样性是否与栖息地适合性有关？（3）特定表型是否因具有独有的环境变异模式而在逆梯度顺梯度变异连续谱占据独有的位点？（4）表型临界环境变化速率是否与栖息地特异性和适合性有关？申请人拟用同园实验收集18个表型数据，计算Qst，用每种9个微卫星标记以及其它核和线粒体标记计算Fst，通过对比Qst与Fst判定表型是否受选择并与局域适应有关。申请人将基于谱系ANOVA、谱系ANCOVA和PGLS揭示表型与地理分布和局域环境之间的关联性，并利用上述提供不同遗传多样性信息的分子标记分析种群遗传多样性与栖息地适合性之间的关系，推测种群进化时长对遗传多样性的影响。

Uncovering the underlying mechanism for ecological adaptation of organisms to local environments is a central goal of evolutionary biology. Species or populations inhabiting environmentally heterogeneous regions provide an excellent opportunity in this respect. The selective forces imposed by local environments and phenotypes under selection have been studied in a wide range of vertebrate taxa, but not including any lizard species. Here, we use lizards of three species within the Phrynocephalus vlangalii species complex endemic to China as model animals to address four questions: (1) Are fitness-related phenotypes phylogenetically independent, thus varying more tightly with species’ distribution and local environment? (2) Is genetic diversity of a population determined by habitat suitability? (3) Does a given phenotype have an unique pattern of geographic variation, thus having an unique position in the continuum of cogradient-countergradient variation? (4) Is the critical rate of environmental change for a phenotype correlated with both habitat speciality and habitat suitability? We will conduct a series of common garden experiments to collect data on 18 morphological, physiological and life-history variables (phenotypes) and then calculate Qst for each phenotype. We will use 9 microsatellite, 3 nDNA (RAG1、PRLR and PDC) and 3 mtDNA (Cyt b、ND4 and COI) marks to resolve phylogenetic relationships among species within the complex and intra-specific units, and to calculate Fst. We will contrast Qst with Fst to show whether a phenotype is selected and thus locally adapted. We will use phylogenetic ANOVA, phylogenetic ANCOVA or phylogenetic generalized least squares to determine associations of currently observed patterns of phenotypic variation with species' distribution and local environment. We will use genetic information provided by different types of molecular marks to examine the relationship between population genetic diversity and habitat suitability, and the effect of population evolution duration on population genetic diversity. Hypotheses to be tested in this study include: (1) phenotypes should be similar among species and lineages of the same species if they are phylogenetically independent and tightly correlated with local environment; (2) population genetic diversity should be higher in the region where habitat suitability if it varies geographically; (3) phenotypes should have unique positions in the continuum of cogradient-countergradient variation if their evolutionary and plastic responses to selection differ from each other; and (4) the critical rate of environmental change for a phenotype should be slower in species with a smaller rage it the rate is correlated with both habitat speciality and habitat suitability. Data generated from this study will allow us to better understand how lizards of the Phrynocephalus vlangalii species complex adapt to local environments and, more importantly, they might provide insight into the evolutionary divergence of viviparous Phrynocephalus species as the consequence of environmental change associated with uplift of the Qinghai-Tibet Plateau.