The order Charadriiformes comprises three major clades: Lari and Scolopaci as sister group to Charadrii. Until now,
only three Charadriiformes species have been studied by chromosome painting: Larus argentatus (Lari), Burhinus
oedicnemus and Vanellus chilensis (Charadrii). Hence, there is a lack of information concerning the third clade,
Scolapaci. Based on this, and to gain a better understanding of karyotype evolution in the order Charadriiformes, we
applied conventional and molecular cytogenetic approaches in a species belonging to clade Scolopaci - the wattled
jacana (Jacana jacana) - using Gallus gallus and Zenaida auriculata chromosome-specific probes. Cross-species
evaluation of J. jacana chromosomes shows extensive genomic reshuffling within macrochromosomes during evolution, with multiple fission and fusion events, although the diploid number remains at high level (2n=82). Interestingly,
this species does not have the GGA7-8 fusion, which was found in two representatives of Charadrii clade, reinforcing
the idea that this fusion may be exclusive to the Charadrii clade. In addition, it is shown that the chromosome evolution in Charadriiformes is complex and resulted in species with typical and atypical karyotypes. The karyotypic features of Scolopaci are very different from those of Charadrii and Lari, indicating that after divergence, each suborder
has undergone different chromosome rearrangements.
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