The biometrical effect of inversions on body size is due to genetic differences between rearrangements and not to the historical relationship between the populations studied.
Genetic variation in correlations among size-related traits of head, thorax and wings are examined in D.buzzatii by comparing the pattern of the Phenotypic Correlation Matrix between inversion karyotypes of the second chromosomes. Results indicate chromosome inversions are factors affecting genetic correlations among traits known to be phenotypically correlated with adult fitness components.
Rearrangements are correlated with a large thorax size.
Dbuz\Galileo insertions lie at both Dbuz\In(2)j inversion breakpoints not present in the "2 standard" (2st) progenitor chromosome. 7bp sequences, like target site duplications, flank the insertions, but the duplicated sequences are separated and inverted, suggesting that Dbuz\In(2)j arose by intrachromosomal pairing and recombination between the two homologous sequences inserted in distant sites in opposite orientations. All versions of Dbuz\In(2)j tested (21 lines) show the same pattern of Dbuz\Galileo insertion, suggesting that the Dbuz\In(2)j arrangements are monophyletic.