Eon in Earth history, consisting of the most recent 570 million years. It comprises the Palaeozoic, Mesozoic, and Cenozoic eras. The vast majority of fossils come from this eon, owing to the evolution of hard shells and internal skeletons. The name means interval of well-displayed life.
Modelled on the French tricolour, the vertical stripes represent liberty and revolution. The almost square proportions of the flag are unusual. Effective date: 23 January 1831.