Interesting.

The eye is perhaps one of the best examples of Darwinian evolution. Incremental steps driven by natural selection have led to the evolution of this complex organ from its origin as a simple light-sensitive eye spot.
But what is the precise origin of this organ, specialised for vision, within the animal kingdom? A paper published today in Proceedings of the National Academy of Sciences (PNAS) seeks to address this question by examining an importa…