Fig. 2.

Maximum parsimony tree obtained after PAUP analysis of chromosomal characters found in representative species of Vampyressinae bats. Numbers above branch are Bremer decay index and bootstrap values for 1000 replicates and below are the shared syntenic blocks. The abbreviations of the name of species are detailed in Table 1. The characters “Y/15 acro” and “Y/15 meta” are different chromosomes and resulted from different rearrangements. While in the character 9/13 includes both these chromosomes in full, 9q/13 includes the 13 and the long arm of 9. Figure 3 details the evolution of the sex chromosome systems; note that it matches perfectly with the phylogeny shown here