Fig. 4.

Phylogenetic distribution of RP gene introns in eukaryotes. Representative eukaryotes from each eukaryotic supergroup were examined for intron insertion at the same conserved position within Rps4 (blue), Rps24 (red) and Rpl7a (green) [16] genes and the distribution for each intron was mapped onto a eukaryotic tree by Burki (2014) [30]. The number of species containing an intron (numerator) and the number sampled (denominator) are indicated for each eukaryotic group (See Additional file 8 for organism names). Coloured lines indicate extant eukaryotic groups which contain each intron to the predicted last common ancestor to contain each respective RP gene intron