Blacksburg, Va., October 12, 2006 -- A group of 15 scientists from five countries has discovered evidence of cell differentiation in fossil embryos that are more than 550 million years old. They also report what appear to be cells about to divide. They used x-ray imaging technologies that produce higher resolutions than hospital-CT scans and digitally extracted cells from the embryos of ancient animals that have been preserved in the Doushantuo Formation, a fossil site in South China.
The discovery will be reported in the Oct. 13 issue of Science, in the article, "Cellular and Subcellular Structure of Neoproterozoic Animal Embryos," by James W. Hagadorn of Amherst College, Shuhai Xiao of Virginia Tech, Philip C.J. Donoghue of the University of Bristol, Stefan Bengtson of the Swedish Museum of Natural History, Neil J. Gostling and Maria Pawlowska of Bristol, Elizabeth C. Raff and Rudolf A. Raff of both Indiana University and the University of Sydney, F. Rudolph Turner of Indiana, Yin Chongyu of the Chinese Academy of Geological Sciences, Chuanming Zhou and Xunlai Yuan of the Nanjing Institute of Geology and paleontology, Matthew B. McFeely of Amherst, Marco Stampanoni of Swiss Light Source at the Paul Scherrer Institute, and Kenneth H. Nealson of the University of Southern California, L.A.
"We asked the question Can subcellular or intracellular structures be preserved within these embryos," said Xiao, associate professor of geosciences at Virginia Tech who has been exploring the Doushantuo Formation for many years and whose group reported the discovery of animal embryo fossils from this formation (Nature, 1998).
"Because the fossils are so small, we used microfocus x-ray computed tomography (microCT), scanning electron microscope, and transmission electron microscope facilities at Amherst College, Swiss Light Source at the Paul Scherrer Institute in Switzerland, Virginia Tech, and Nanjing Institute of Geology and Paleontology
Contact: Susan Trulove