Smithsonian Conservation Biology Institute, National Zoological Park Washington, DC, USA ; Department of Environmental Science and Policy, George Mason University Fairfax, VA, USA.
Evol Appl. 2013 Sep;6(6):949-59. doi: 10.1111/eva.12078. Epub 2013 Jun 6.
Gene flow is a critical ecological process that must be maintained in order to counteract the detrimental effects of genetic drift in subdivided populations, with conservation benefits ranging from promoting the persistence of small populations to spreading adaptive traits in changing environments. We evaluated historical and contemporary gene flow and effective population sizes of leopards in a landscape in central India using noninvasive sampling. Despite the dramatic changes in land-use patterns in this landscape through recent times, we did not detect any signs that the leopard populations have been through a genetic bottleneck, and they appear to have maintained migration-drift equilibrium. We found that historical levels of gene flow (mean m h = 0.07) were significantly higher than contemporary levels (mean m c = 0.03), and populations with large effective population sizes (Satpura and Kanha Tiger Reserves) are the larger exporters of migrants at both timescales. The greatest decline in historical versus contemporary gene flow is between pairs of reserves that are currently not connected by forest corridors (i.e., Melghat-Pench m h - m c = 0.063; and Kanha-Satpura m h - m c = 0.054). We attribute this reduction in gene flow to accelerated fragmentation and habitat alteration in the landscape over the past few centuries, and suggest protection of forest corridors to maintain gene flow in this landscape.
基因流是一个关键的生态过程，必须加以维持，以抵消分裂种群中遗传漂变的不利影响，其保护效益范围从促进小种群的持续存在到在不断变化的环境中传播适应性特征。我们使用非侵入性采样方法评估了印度中部景观中豹子的历史和当代基因流和有效种群大小。尽管该景观的土地利用模式在最近发生了巨大变化，但我们没有发现任何迹象表明豹子种群经历了遗传瓶颈，它们似乎保持了迁移-漂变平衡。我们发现，历史水平的基因流（平均 m h = 0.07）明显高于当代水平（平均 m c = 0.03），而有效种群规模较大的种群（萨塔拉和坎哈老虎保护区）在两个时间尺度上都是较大的移民输出者。历史与当代基因流之间最大的下降是在目前没有森林走廊连接的保护区之间（即，梅尔格特-彭奇 m h - m c = 0.063；以及坎哈-萨塔拉 m h - m c = 0.054）。我们将这种基因流的减少归因于过去几个世纪来景观的快速破碎化和栖息地的改变，并建议保护森林走廊，以维持该景观中的基因流。
