Buchnera symbionts supplement host aphids with essential nutrients absent from their diet. Pictured are pea aphid, Acyrthosiphon pisum, embryos at stage 7, 13 and 17. Aphid DNA is stained blue and symbiont DNA is pseudocolored green. By stage 17 symbionts are housed in aphid bacteriocyte cells forming a bacteriome. These confocal microscopy images were generated by in Alex Wilson's laboratory at the University of Miami by Hsiao-Ling Lu from National Taiwan University with funding from National Science Foundation Award 1121847 and National Science Council of Taiwan NSC 102-2917-I-002-006.