We at Webvision have a fascination with the evolution of the eye and are always looking for interesting papers that help describe from where, how and when vision came. This paper, Molecular analysis of the amphioxus frontal eye unravels the evolutionary origin of the retina and pigment cells of the vertebrate eye by Pavel Vopalenskya, Jiri Pergnera, Michaela Liegertova, Elia Benito-Gutierrez, Detlev Arendt, and Zbynek Kozmika attempts to answer the question of where the vertebrate eye came from. While the amphioxus has for many years been recognized as a viable candidate for the earliest vertebrate eye, the retinal structure is different from that of other vertebrates. Specifically, the photoreceptors of amphioxus are simple ciliated cells as opposed to the more sophisticated elaborations of structures on top of cillia in other vertebrate retinas. This paper describes in molecular terms, gene coexpression and structural features the different cell types of amphioxus in an attempt to define neuronal circuitry. Its a very cool paper that provides additional detail into the evolutionary origins of vision and we encourage you to have a look.
Image Credit: Hans Hillewaert from Wikipedia