This is a collage that represents three periods of Neoproterozoic and is composed of three images from Commons: File:Otavia antiqua 3D reconstruction.jpg represents Tonian period (1000-720 mya), marked by start of evolution of animals. File:AntarcticaDomeCSnow.jpg represents Cryogenian period (720-635 mya), marked by worldwide glaciations (aka "Snowball Earth"). File:Life in the Ediacaran sea.jpg represents Ediacaran period (635-541 mya), marked by first recognizable animal fauna - vendobionts.