Historical population size change and differentiation of relict populations of the endangered giant kangaroo rat

From a conservation management perspective it is important to understand how genetic diversity is partitioned across a species’ range, including (1) identification of evolutionarily distinct units versus those recently isolated through anthropogenic activities and (2) the relative genetic contributions among components of fragmented (meta)populations. To address these questions, we investigated the phylogeography and metapopulation structure among relict populations of the endangered giant kangaroo rat (Dipodomys ingens) in the highly altered San Joaquin Desert Ecosystem. This keystone species underwent a ~97% range reduction over the past century, resulting in a current range that is highly fragmented, with two dominant northern and southern populations occurring 150 km apart. We sequenced >800 bp of mitochondrial DNA and genotyped 17 nuclear microsatellites in >275 D. ingens to assess the evolutionary relationship of these populations as well as the genetic structure within the ...