PDF(Pubmed)
Abstract：
There is a general expectation that urban populations will be fragmented and the movement of individuals will be restricted leading to low effective population sizes, low genetic diversity, higher inbreeding, and higher differentiation than populations living in more continuous habitat. In this study, we compare the genetic diversity and differentiation of Texas horned lizards that are found in four small towns (Kenedy, Karnes City, Rockdale, and Smithville) in Texas and at Tinker Air Force Base, Oklahoma to populations that occur in 16 natural areas and to an introduced population in South Carolina. We also present more detailed spatial genetic data and home range data for several of the towns. Texas horned lizards (Phrynosoma cornutum) living in small towns have lower genetic diversity, higher differentiation, and smaller effective population sizes than populations located in more natural areas. There was evidence for human-mediated movement of lizards into town; however, it has not been enough to counteract the effects of drift. Home range size is smaller in town than in more natural areas. Genetic patterns suggest dispersal occurs over short distances and is inhibited across areas with a high percent of impervious surface and major roads. These data suggest that effective planning to maintain suitable habitat and corridors to facilitate movement is critical to maintaining small terrestrial species like the Texas horned lizard and must be integrated into the early stages of urban development.
摘要：
人们普遍预计，城市人口将支离破碎，个人流动将受到限制，导致有效人口规模低，低遗传多样性，较高的近亲繁殖，和更高的分化比人口生活在更连续的栖息地。在这项研究中,我们比较了在四个小城镇发现的德克萨斯有角蜥蜴的遗传多样性和分化(Kenedy，卡恩斯市，Rockdale,和史密斯维尔）在德克萨斯州和廷克空军基地，俄克拉荷马州的人口分布在16个自然地区，以及南卡罗来纳州的引进人口。我们还提供了一些城镇的更详细的空间遗传数据和家庭范围数据。生活在小城镇的得克萨斯州有角蜥蜴（Phrynosomacornutum）的遗传多样性较低，更高的分化，与位于更自然区域的人口相比，有效人口规模更小。有证据表明人类介导的蜥蜴进入城镇；然而，这还不足以抵消漂移的影响。家庭范围的大小是较小的城镇比在更自然的地区。遗传模式表明，传播发生在短距离内，并且在不透水表面和主要道路占很高比例的地区受到抑制。这些数据表明，有效的规划以维持合适的栖息地和走廊以促进移动对于维持德克萨斯州有角蜥蜴等小型陆地物种至关重要，必须将其纳入城市发展的早期阶段。
