Distribution of 45S rDNA sites in the arm frame. Chromosomes are represented as grey lines aligned by centromeres (0) and sites as short bold lines. 46 chromosomes with sites in both arms were drawn twice in opposite directions. Sample size: 419 angiosperms and 38 gymnosperms karyotypes (383 and 37 species, respectively).
Roa and Guerra BMC Evolutionary Biology 2012 12:225 doi:10.1186/1471-2148-12-225