Challenges to assessing connectivity between massive populations of the Australian plague locust
Challenges to assessing connectivity between massive populations of the Australian plague locust
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DOI：
10.1098/rspb.2010.2605
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发表时间：
2011-10-22
影响因子：
4.7
通讯作者：
Sword, Gregory A.
中科院分区：
文献类型：
--
作者：
Chapuis, Marie-Pierre;Popple, Julie-Anne M.;Sword, Gregory A.
将人口和遗传扩散措施联系起来对运动生态学和进化具有重要意义。然而，这种整合可能是困难的，特别是对于繁殖力很强的物种，它们往往是根据对人口流动的了解作出管理决策的目标。在这里，我们提出了一个例子，说明大人口规模的影响如何阻止遗传方法评估人口结构，即使是在大陆范围内。澳大利亚的蝗灾，即尾蝗，是一种重要的害虫，迄今为止，澳大利亚东部和西部的蝗灾种群一直受到独立监测和管理。我们利用微卫星对相隔3000公里的12个C. terminifera种群样本进行了遗传变异评估。传统的汇总统计表明，在整个范围内，遗传多样性水平很高，种群结构却令人惊讶地缺乏。近似贝叶斯计算表明，黄花蓟马的遗传多样性水平保守地对应于数万至数百万个体的有效种群规模。我们使用这些估计和计算机模拟来估计最小的扩散速率m，这可以解释观察到的范围内的遗传同质性。澳大利亚大陆两岸之间的分散率可能比通常认为的人口连通性所需的分散率低几个数量级。
Linking demographic and genetic dispersal measures is of fundamental importance for movement ecology and evolution. However, such integration can be difficult, particularly for highly fecund species that are often the target of management decisions guided by an understanding of population movement. Here, we present an example of how the influence of large population sizes can preclude genetic approaches from assessing demographic population structuring, even at a continental scale. The Australian plague locust, Chortoicetes terminifera, is a significant pest, with populations on the eastern and western sides of Australia having been monitored and managed independently to date. We used microsatellites to assess genetic variation in 12 C. terminifera population samples separated by up to 3000 km. Traditional summary statistics indicated high levels of genetic diversity and a surprising lack of population structure across the entire range. An approximate Bayesian computation treatment indicated that levels of genetic diversity in C. terminifera corresponded to effective population sizes conservatively composed of tens of thousands to several million individuals. We used these estimates and computer simulations to estimate the minimum rate of dispersal, m, that could account for the observed range-wide genetic homogeneity. The rate of dispersal between both sides of the Australian continent could be several orders of magnitude lower than that typically considered as required for the demographic connectivity of populations.