Phylogeny of Chromosome III inversion polymorphism in Drosophila pseudoobscura

The Standard (ST) arrangement of Chromosome III is related to the Arrowhead (AR) pattern by a paracentric inversion involving about a third of the chromosome. Other chromosome polymorphisms involve multiple inversions, and inversions-within-inversions. Reconstruction of the pattern of inversions allows the phylogeny of the inversions patterns to be reconstructed (below).