1. G. S. Dwyer and P. A. Baker, Department of Geology, Duke University, Durham, NC 27708, USA.
2. T. M. Cronin, U.S. Geological Survey, Branch of Paleontology and Stratigraphy, Mail Stop 970 National Center, Reston, VA 22092, USA.
3. M. E. Raymo, Department of Earth, Atmospheric, and Planetary Sciences, Massachusetts Institute of Technology, Cambridge, MA 02139, USA.
4. J. S. Buzas, Department of Mathematics and Statistics, University of Vermont, Burlington, VT 05051, USA.
5. T. Corrège, Départment de Géologie et Océanographie, Université de Bordeaux I, Avenue des Facultés, Bordeaux, France.