Annelid eye evolution revealed by developmental, ultrastructural, and connectome analyses of cerebral eyes in Malacoceros fuliginosus
By integrating developmental, molecular, ultrastructural, and connectomic analyses of *Malacoceros fuliginosus*, this study reveals that its diverse cerebral eyes are homologous, inverted rhabdomeric structures that likely originated from an ancestral duplication event, providing a unified framework for understanding annelid eye evolution.