" The role of bolide impacts on the history of life during other portions of the Phanerozoic Eon is less clear (see Raup and Fischer, both this volume), and catastrophic changes unrelated to extraterrestrial processes may have been important (see Holser, this volume).

Contributions by: H.D. Holland, A.F. Trendall, H. Füchtbauer, D.P. McKenzie, D.M. Raup, E.R. Oxburgh, A. Seilacher, G.J. Wasserburg, W.H. Berger, K.S. Deffeyes, K. Padian, F.M. Richter, A.B. Thompson