Now, a research team from Virginia Tech and Nanjing Institute of Geology and Paleontology has discovered uniquely well-preserved fossil forms from 550-million-year-old rocks of the Ediacaran Period. The research appears in the Proceedings of the National Academy of Sciences. The discovery of these unusually preserved fossils reveals unprecedented information about the body construction of macroscopic organisms more than a half billion years ago. Ediacara fossils are some of the oldest fossils with large body size and complex morphology. "Present in rocks ranging from 575 to 540 million years in age, these fossils provide the key to understand the prelude to the Cambrian Explosion when animals with skeletons and familiar morphologies began to bloom about 540 to 520 million years ago," says Shuhai Xiao, a geoscientist from Virginia Tech. "However, classic Ediacara fossils are mostly preserved in sandstone, and the coarse sand grains limit how much we can learn about the fine-scale morphologies of these fossils."