Note: NS indicates not significant. Maj P and Min P represent as major and minor parents. BP denote Breakpoint. The numbers in parentheses are BP locations in the recombinant nucleotide sequences without gaps. The values after the semicolon are Max Chi values for that BPs. **indicateP < 0.01.

Considering that the evolutionary history of each domain might have been different, we tested each domain separately for evidence of positive selection. Selection statistics by traditional methods did not disclose any statistical significant signal of selection that deviate from neutral expectations for turdus enumus (Tajima’s D: -0.87309, P > 0.10; Fu & Li’s D* test statistic: 0.36, P > 0.10; Fu & Li’s F* test statistic: 0.03, P > 0.10) and turdus atrogularis (Tajima’s D: -0.86107, P > 0.10 Fu & Li’s D* test statistic: 0.19, P > 0.10; Fu & Li’s F* test statistic: -0.077, P > 0.10). Still, overall d_N value was significantly higher statistically than dS in Turdus atrogularis ( 1.687) and ratio d_N/ds was more pronounced at codons presumably coding PBR (1.994) than codons not involved in such activity (0.884) is presented in (Table 3).

TABLE 3: The average rates of nonsynonymous (d_N), synonymous (ds) substitutions and the result of Z-test, the average nucleotide distances (d_nt) and amino acid distances (d_aa) for PBR, non-PBR and all sites in MHC class I of Turdidae family.