Fossils of Oldest Embryos (IMAGE) Virginia Tech Caption Shown are scanning electron photomicrographs of two fossil embryo specimens from the 600-million-year-old Doushantuo Formation in South China. The soccer-ball-shaped specimen is interpreted as an early stage (blastula) embryo, and the baseball-shaped specimen is interpreted as an intermediate-stage helical embryo consisting of three clockwise coils. Each embryo used to be enclosed in an envelope, which was removed (some piece still remains in the soccer-ball-shaped specimen) so that the embryo itself is exposed. Embryos are about 0.55-0.75 millimeter in diameter. Background shows the Doushantuo rocks from which the embryos were extracted. Credit Shuhai Xiao Usage Restrictions use with mention of Dr. Xiao's research License Licensed content Disclaimer: AAAS and EurekAlert! are not responsible for the accuracy of news releases posted to EurekAlert! by contributing institutions or for the use of any information through the EurekAlert system.