Chinese scientists have discovered a 600 million-year-old sponge-like fossil, predating existing findings of primitive animals by 60 million years. The Nanjing Institute of Geology and Paleontology at the Chinese Academy of Sciences on Monday said that the tiny fossil, which only measures two to three cubic millimeters, was discovered in the Weng'an biota in the southwest province of Guizhou. The discovery indicates that primitive sponge- and Eumetazoa-like animals lived before the Cambrian period, which is between 541 million and 485 million years ago, much earlier than previously assumed. (Photo/ Xinhua)