Figure 1. Ctenophores and their innovations.
a, The sea gooseberry, Pleurobrachia bachei (Fig. 1S) was selected as a target for genome sequencing due to preservation of traits ancestral for this lineage and since in situ hybridization/immunolabeling is possible. b–d: Major ctenophore innovations. b, Nervous system revealed by tyrosinated α-tubulin immunolabeling; c, Scanning electron microscopy (SEM) imaging of nerve net in a tentacle pocket (scale:15μm). d, Locomotory ciliated combs (SEM, scale:100μm). e, Glue-secreting cells – Colloblasts in tentacles (SEM, scale:50μm). f, Relationships among major animal clades with Choanoflagellates sister to all Metazoa.