Cambrian Explosion: Carl Zimmer\'s column (Introduction)
A lot of sound and fury but nothing solid, except supposition and conjecture:-http://www.nytimes.com/2013/09/20/science/new-approach-to-explaining-evolutions-big-bang.html?_r=0-Also an interview with one of the scientists quoted:-http://www.sciencemag.org/content/suppl/2013/09/18/341.6152.1409-b.DC1/SciencePodcast_130920.pdf-Again lots of conjecture.