Rapid genetic restoration of a keystone species exhibiting delayed demographic response

Genetic founder effects are often expected when animals colonize restored habitat in fragmented landscapes, but empirical data on genetic responses to restoration are limited. We examined the genetic response of banner-tailed kangaroo rats (Dipodomys spectabilis) to landscape-scale grassland restoration in the Chihuahuan Desert of New Mexico, USA. D. spectabilis is a grassland specialist and keystone species. At sites treated with herbicide to remove shrubs, colonization by D. spectabilis is slow and populations persist at low density for ≥10 yrs (≥6 generations). Persistence at low density and low gene flow may cause strong founder effects. We compared genetic structure of D. spectabilis populations between treated sites and remnant grasslands, and we examined how the genetic response to restoration depended on treatment age, area, and connectivity to source populations. Allelic richness and heterozygosity were similar between treated sites and remnant grasslands. Allelic richness at t...

在破碎化景观中，动物定植于修复后的生境时通常会出现遗传奠基者效应（genetic founder effects），但目前关于修复对种群遗传影响的实证数据仍较为匮乏。本研究以美国新墨西哥州奇瓦瓦沙漠的旗尾更格卢鼠（Dipodomys spectabilis，banner-tailed kangaroo rats）为对象，探究其对景观尺度草地修复的遗传响应。旗尾更格卢鼠为草地特化种，同时也是关键物种（keystone species）。在使用除草剂清除灌木的修复样地中，该鼠的定植过程较为缓慢，种群以低密度持续存在至少10年（即至少6个世代）。低密度存续与低基因流可能引发强烈的遗传奠基者效应。我们对比了修复样地与残存草地中旗尾更格卢鼠种群的遗传结构，并分析了修复的遗传响应如何受修复时长、样地面积以及与源种群连通性的影响。修复样地与残存草地的等位基因丰富度（allelic richness）与杂合度（heterozygosity）水平相近。t时刻的等位基因丰富度...