SUBSTANCE is a realtime 3D application for producing photorealistic Evolutionary Art.
SUBSTANCE allows you to create and animate organic forms and structures.

The free version of SUBSTANCE is now available for download.
Registering is not necessary to get it.

[link]

But, what is Organic / evolutionary Art?

Organic (Evolutionary) Art, which is virtually exclusively generated on computers, exploits the process of evolution to create an artwork which continually changes according to an evolutionary algorithm. The idea is to use genetic algorithms to evolve shapes based on their aesthetics. Basically, the artist is able to control the development of a piece of work through some form of "selection", in a manner analogous to natural selection. In a system such as SUBSTANCE, one or more parent virtual sculptures are mutated and/or crossbred to produce a number of "children", which are then selected again. These results are then used to produce the next "generation".

Evolutionary systems allow the artist to generate complex computer artwork without them needing to delve into the actual programming used.

[link]