MtDNA analysis
Aligned sequences of a 381 bp section of the control region (CR) (n=224
individuals) and a 370 bp section of the cytochrome B gene (cytb )
(n=228 individuals) were obtained. The CR was more polymorphic revealing
21 haplotypes compared to cytb, where only five haplotypes were
detected. A total of 204 individuals have been sequenced at both regions
and the mitochondrial diversity estimates of the combined sequences (751
bp in total) were summarized in Table 1. A total of 24 haplotypes (h)
were observed, with 11 found within the wild UK birds and six within the
wild Greek birds. Our dataset revealed that there was greater
mitochondrial diversity within the wild UK birds (haplotype diversity =
0.776) than within the wild Greek birds (haplotype diversity = 0.439).
This pattern was also mirrored within the captive stocks of both
countries, with the UK captive stocks (hd=0.786) having a higher
diversity than the Greek captive stocks (hd=0.409). Surprisingly, the
wild-caught birds from North Macedonia had the highest haplotype
diversity (hd=0.833). The three sampling locations with the highest
haplotype diversity were all from different countries, East Lothian
(hd=0.868; Scotland), Kumanovo (hd=0.822; North Macedonia) and Kozani
(hd=0.757; Greece). This is contrasted with the two lowest estimates,
also from different countries, Fife (hd=0.182; Scotland) and Drama
(hd=0; Greece).
The haplotype networks revealed and confirmed the eastern and western
lineages in both the cytb and CR sequences (Figures 2 and 3). The
inclusion of the haplotypes by (Liukkonen-Anttila et al. , 2002)
in our network of the control region sequences, verified the structuring
of our samples into the Western and Eastern lineages since all wild
birds in the UK had a western mitochondrial haplotype while all wild
birds in Greece showed an Eastern haplotype. The two populations from
North Macedonia had a mix of birds as indicated by the networks, based
on the CR data, most of the birds had an eastern haplotype (69%, n=11)
and some possessed a western haplotype (31%, n=5).
The analysis also revealed that 17 new haplotypes (eight western and
nine Eastern) exist within our control-region dataset that were not
observed by the previous study. The most striking observation is the
clustering of all Greek captive individuals within the Western lineage,
showing higher relatedness with the wild birds from the UK rather than
those in Greece.