Guess how was this image drawn!.

Right, I think I am allowed to be a little geeky sometimes.

This nice image of a beach in fluorescent colours is not drawn with some of those japanese markers: it is actually bacteria growing on a Petri dish. How come they fluoresce, and in different colours?. Well, it is because they are genetically modified.

The green fluorescent protein (GFP) is a protein found in a bioluminescent jellyfish that, as the name says, produces green light when stimulated. GFP is not a very fuzzy protein, so you can isolate its gene (DNA sequence) from the jellyfish, put it into another organism (under suitable regulation) and make the organism fluoresce.

In that way, scientist have generated not only fluorescent bacteria, but also fluorescent mice, rats, pigs and even monkeys.

If you make some changes in the structure of the protein, you can generate variants that produce blue, yellow, cyan or red light.

Then, if you have bacteria expressing all these varieties in your lab and you happen to be bored waiting during an incubation period, you can create images such as the one shown here.

(Taken from Wikipedia, artwork by Nathan Shaner and photography by Paul Steinbach).