Diversity and Evolution of and Transposons in the Apoidea Genomes.

Bees (Apoidea), the largest and most crucial radiation of pollinators, play a vital role in the ecosystem balance. Transposons are widely distributed in nature and are important drivers of species diversity. However, transposons are rarely reported in important pollinators such as bees. Here, we surveyed 37 bee genomesin Apoidea, annotated the and transposons in the genome of each species, and performed a phylogenetic analysis and determined their overall distribution. The and families showed high diversity and low abundance in the 37 species, and their proportion was significantly higher in solitary bees than in social bees. DD34D/ was found to be distributed in almost all species and was found in , , and and may still be active. Using horizontal transfer analysis, we found that DD29-30D/ may have experienced horizontal transfer (HT) events. The current study displayed the evolution profiles (including diversity, activity, and abundance) of the and transposons across 37 species of Apoidea. Our data revealed their contributions to the genomic variations across these species and facilitated in understanding of the genome evolution of this lineage.