The Saffron finch (Sicalis flaveola), a semi-domestic species, is tolerant of human proximity
and nesting in roof spaces. Considering the importance of cytogenomic approaches in revealing
different aspects of genomic organization and evolution, we provide detailed cytogenetic data for S.
flaveola, including the standard Giemsa karyotype, C- and G-banding, repetitive DNA mapping, and
bacterial artificial chromosome (BAC) FISH. We also compared our results with the sister groups,
Passeriformes and Psittaciformes, bringing new insights into the chromosome and genome evolution
of birds. The results revealed contrasting rates of intrachromosomal changes, highlighting the role of
SSR (simple short repetition probes) accumulation in the karyotype reorganization. The SSRs showed
scattered hybridization, but brighter signals were observed in the microchromosomes and the short
arms of Z chromosome in S. flaveola. BACs probes showed conservation of ancestral syntenies of
macrochromosomes (except GGA1), as well as the tested microchromosomes. The comparison of our
results with previous studies indicates that the great biological diversity observed in Passeriformes
was not likely accompanied by interchromosomal changes. In addition, although repetitive sequences
often act as hotspots of genome rearrangements, Passeriformes species showed a higher number of
signals when compared with the sister group Psittaciformes, indicating that these sequences were
not involved in the extensive karyotype reorganization seen in the latter.
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