Contents

25 June 1999
Vol 284, Issue 5423

About The Cover

Cover image expansion

COVER Fossils of the large (15 to 30 cm), soft-bodied organism Pteridinium simplex are locally abundant in sandstone beds of the terminal Proterozoic (~550-million-year-old) Nama Group in Namibia. New insights from paleontology, geochemistry, and molecular genetics are collectively illuminating the pattern, developmental basis, and environmental context of early animal evolution. These insights are part of the special section on evolution beginning on page 2105 [Image: A. H. Knoll]