Connectionists: New paper on why modules evolve, and how to evolve modular neural networks

[Jeff Clune]

Hello all,

I believe that many in the neuroscience community will be interested in a new paper that sheds light on why modularity evolves in biological networks, including neural networks. The same discovery also provides AI researchers a simple technique for evolving neural networks that are modular and have increased evolvability, meaning that they adapt faster to new environments. 

Cite: Clune J, Mouret J-B, Lipson H (2013) The evolutionary origins of modularity. Proceedings of the Royal Society B. 280: 20122863. http://dx.doi.org/10.1098/rspb.2012.2863 (pdf)

Abstract: A central biological question is how natural organisms are so evolvable (capable of quickly adapting to new environments). A key driver of evolvability is the widespread modularity of biological networks—their organization as functional, sparsely connected subunits—but there is no consensus regarding why modularity itself evolved. Although most hypotheses assume indirect selection for evolvability, here we demonstrate that the ubiquitous, direct selection pressure to reduce the cost of connections between network nodes causes the emergence of modular networks. Computational evolution experiments with selection pressures to maximize network performance and minimize connection costs yield networks that are significantly more modular and more evolvable than control experiments that only select for performance. These results will catalyse research in numerous disciplines, such as neuroscience and genetics, and enhance our ability to harness evolution for engineering purposes.

Video: http://www.youtube.com/watch?feature=player_embedded&v=SG4_aW8LMng

There has been some nice coverage of this work in the popular press, in case you are interested:

• National Geographic: http://phenomena.nationalgeographic.com/2013/01/30/the-parts-of-life/
• MIT's Technology Review: http://www.technologyreview.com/view/428504/computer-scientists-reproduce-the-evolution-of-evolvability/ 
• Fast Company: http://www.fastcompany.com/3005313/evolved-brains-robots-creep-closer-animal-learning
• Cornell Chronicle: http://www.news.cornell.edu/stories/Jan13/modNetwork.html
• ScienceDaily: http://www.sciencedaily.com/releases/2013/01/130130082300.htm

I hope you enjoy the work. Please let me know if you have any questions. 

Best regards,
Jeff Clune

Assistant Professor
Computer Science
University of Wyoming
jeffclune at uwyo.edu
jeffclune.com