Biology
 
Biology (2003) is a three movement work by composer Luke DuBois, and is part of an ongoing series of works he has created that investigate the application of genetic computer algorithms towards music composition.  Put simply, a genetic algorithm is a computer program that creates successive "generations" of output in which procedures similar to biological processes -- mating, chromosomal crossover, mutation, etc. -- are applied to sets of data, in this case, musical materials such as pitch sets and rhythmic motives.  

In these algorithms, as in nature, each successive generation carries the legacy of its predessessors but also moves in new and unexpected directions.

In Biology, each of the three movements uses genetic algorithms to develop both musical and visual material.  Moreover, the video is generated live as the computer listens to the violinist and bases the manipulation of its algorithms upon the actual audio signal it hears at any given moment.  Thus, the violin performance has a significant impact upon the live video as well as its role as interpreter of the musical score.

For more information on this project, including sound and video clips, please see Luke DuBois' dissertation webpage: http://music.columbia.edu/~luke/dissertation