http://www.sciencedaily.com/releases/2014/09/140924211827.htm-"In an effort to determine how, why, and when multicellularity arose from single-celled ancestors, Xiao and his collaborators looked at phosphorite rocks from the Doushantuo Formation in central Guizhou Province of South China, recovering three-dimensionally preserved multicellular fossils that showed signs of cell-to-cell adhesion, differentiation, and programmed cell death -- qualities of complex multicellular eukaryotes such as animals and plants."