Phylogeography of grey partridge
The phylogeographic data produced by (Liukkonen-Anttila et al. , 2002) were used as a basis for comparisons with our dataset. We sequenced an overlapping section of the mitochondrial control region that (Liukkonen-Anttila et al. , 2002) sequenced in individuals sampled across 17 Eurasian countries. One of their main findings was that there was an Eastern/Western split in mitochondrial haplotypes within Europe, suggesting that grey partridge had colonized Europe from two separate glacial refugia. However, only a few samples had been collected in Greece and none within Scotland. In our analysis, we have included a large number of data from these two countries as well as North Macedonia and we found that all wild birds in the UK had a western mitochondrial haplotype. Also consistent with (Liukkonen-Anttilaet al. , 2002), all studied wild birds in Greece belong to Eastern lineage. The fact that the two populations from North Macedonia had a mix of birds, matches the situation in neighboring Bulgaria, perhaps suggesting that these regions of the Balkans are contact zones between the eastern and western lineages (Liukkonen-Anttila et al. , 2002). Alternatively, birds of Western origin may have been released for hunting. However, more research focusing on the Balkans is required to distinguish between these two scenarios.
By comparing the mitochondrial haplotypes to those previously published, we can also gain some limited insight into the origins of the lineages. Most of the wild birds in the UK had the main western haplotype (W1). This occurs throughout Europe in wild and captive stocks (Liukkonen-Anttila et al. , 2002; Andersen and Kahlert, 2012). However, the two other main haplotypes in our UK samples (W17 and W4) had also been previously identified by (Liukkonen-Anttila et al. , 2002) (Figure 3). The haplotype W17 was found in this study in captive birds from Greece and both captive and wild from the UK. A Danish study concluded that this haplotype originates from Bohemia (Czechia) and is found in European captive stocks and Danish populations that were stocked with Bohemian birds between 1895 and 1934 (Andersen and Kahlert, 2012). The captive origin of this haplotype is consistent with our data. The third haplotype that is most common in the UK samples is W4, this haplotype is highly likely to be of French origin based on the study by (Liukkonen-Anttila et al. , 2002). The other haplotypes revealed in our British samples are novel, however, the majority are very similar to the bohemian haplotype (W17). Neither of the two haplotypes that were unique to British wild birds in the previous study was found among our samples. As far as the origin of lineages in Greece, the main eastern haplotype (E1) that has been previously described in Finland, Bulgaria and Ireland (Liukkonen-Anttila et al. , 2002), was the most frequent and widespread haplotype in Greece and it was probably expanded to the area from the Balkan refugia. Five out of seven haplotypes detected in Greece were novel with haplotype E22 and E20 being the second and third most abundant, respectively. North Macedonia consisted of the two most frequent haplotype in Europe (E1 and W1), haplotype E16 with a probable Finish origin and four new haplotypes.
The mitochondrial data is, therefore, of limited use in population assignment; we can accurately use it to identify the presence of Eastern and Western lineages but without a much larger database of historical samples, it is currently difficult to identify the geographic origins of each haplotype, as the majority of British wild birds had haplotypes that are found in captive stocks.