Just saw this in Scientific American:
"...many species of photosynthetic cyanobacteria can swim and swarm to move towards areas where more food–sunlight–is available. Shading some regions will quickly clear them of bacteria, reproducing which areas were bright and which were dark, creating a living photographic image. "
Great article! The iodine staining starch leaves is quite intriguing and the results looks highly detailed.
Maybe one day the engineered bacteria would be an alternative to silver.
This looks a bit like anthrotype, but on living organisms. When using bacteria, I wonder if ther is a way to fix the picture. With leaves and anthrotype there isn't a way to fix.