Temporal genetic analysis of the endangered tidewater goby: metapopulation dynamics or drift in isolation?

Extinction and colonization dynamics are critical to understanding the evolution and conservation of metapopulations. However, traditional field studies of extinction–colonization are potentially fraught with detection bias and have rarely been validated. Here, we provide a comparison of molecular and field-based approaches for assessment of the extinction–colonization dynamics of tidewater goby (Eucyclogobius newberryi) in northern California. Our analysis of temporal genetic variation across 14 northern California tidewater goby populations failed to recover genetic change expected with extinction–colonization cycles. Similarly, analysis of site occupancy data from field studies (94 sites) indicated that extinction and colonization are very infrequent for our study populations. Comparison of the approaches indicated field data were subject to imperfect detection, and falsely implied extinction–colonization cycles in several instances. For northern California populations of tidewater g...灭绝与定殖动态对于理解集合种群（metapopulation）的演化与保护至关重要。然而，传统的灭绝-定殖野外研究可能存在检测偏倚问题，且极少得到验证。本研究针对北加州的潮间带虾虎鱼（Eucyclogobius newberryi）的灭绝-定殖动态，对比了分子生物学方法与野外调查方法的评估效果。我们对北加州14个潮间带虾虎鱼种群的时间序列遗传变异分析，并未发现灭绝-定殖循环预期的遗传变化。同样，对94个样地的野外位点占用数据进行分析后发现，本研究涉及的种群中灭绝与定殖事件极为罕见。两种方法的对比结果显示，野外调查数据存在检测不完美的问题，且在多个案例中错误地推断出了灭绝-定殖循环。针对北加州潮间带虾虎鱼种群的