Studying the evolutionary dynamics of an alien species surviving and continuing to expand after several generations can provide fundamental information on the relevant features of clearly successful invasions. Here, we tackle this task by investigating the dynamics of the genetic diversity in invasive crested porcupine (Hystrix cristata) populations, introduced to Italy about 1500 years ago, which are still growing in size, distribution range and ecological niche. Using genome-wide RAD markers, we describe the structure of the genetic diversity and the demographic dynamics of the H. cristata invasive populations and compare their genetic diversity with that of native African populations of both H. cristata and its sister species, H. africaeaustralis. First, we demonstrate that genetic diversity is lower in both the invasive Italian and the North Africa source range relative to other native populations from sub-Saharan and South Africa. Second, we find evidence of multiple introduction events in the invasive range followed by very limited gene flow. Through coalescence-based demographic reconstructions, we also show that the bottleneck at introduction was mild and did not affect the introduced genetic diversity. Finally, we reveal that the current spatial expansion at the northern boundary of the range is following a leading-edge model characterized by a general reduction of genetic diversity towards the edge of the expanding range. We conclude that the level of genome-wide diversity of H. cristata invasive populations is less important in explaining its successful invasion than species-specific life-history traits or the phylogeographic history in the native source range.

Filtered_RADseq_datasets_crested_porcupineThis file contains three datasets of African porcupines (*Hystrix cristata* and *H. africaeaustralis*) samples as presented in the paper "Long live the alien: is high genetic diversity a pivotal aspect of crested porcupine (*Hystrix cristata*) long-lasting and successful invasion?" doi: 10.1111/mec.13698. Data were produced by single-digestion RAD sequencing using SbfI as restriction enzyme and analyzed in Stacks (Catchen et al. 2013) using denovo_map.pl. Catalogs of RAD loci were exported using export_sql.pl script in the Stacks package and further filtered using the custom python script “loci_selector.py” released as Supplementary Material in the above mentioned publication.Dataset_invasive_crested_porcupine_genomics.tar.gz