A miniscule optimized visual system in the Lower Cambrian Schoenemann, Brigitte ; Liu, Jian-Ni ; Shu, De-Gan ; Han, Jian ; Zhang, Zhi-Fei Abstract Publication: Lethaia Pub Date: September 2009 DOI: 10.1111/j.1502-3931.2008.00138.x Bibcode: 2009Letha..42..265S