Fig. 2.

Phylogenetic distribution of the proportions of TEs in Synalpheus species from the four primary groups that independently evolved eusociality. TE subclasses include DNA transposons (DNA), LTR retrotransposons, LINEs, RCs, SINEs, and TEs with unknown subclass. Eusocial species (■) tended to have more TEs than pair-living species (○) and communal breeding species (△). The increase in the relative abundance of TEs is influenced by different TE subclasses in different species. The phylogenetic tree [based on Chak et al. (42)] on the left depicts the relationships among species. Colors in the bar graphs represent major TE subclasses that are defined in the Inset. The gray boxes separate the four major Synalpheus clades, those with pair-living and eusocial species (the paraneptunus and rathbunae clades), with pair-living and communal breeding species (longicarpus clade), and with pair-living, communal breeding, and eusocial species (brooksi clade). SI Appendix, Fig. S3 depicts the interspecific difference within each TE subclass.