A new model of mass extinctions

Distribution of extinction sizes constructed from original fossil records e xhibits not a single, but a double power-law, with tail exponents being rou ghly the same in different scales, i.e., for species, families and orders. Moreover, time correlations of extinction sizes decrease with a power-law s uggesting long range dependence and/or criticality in extinction events. A thorough analysis of paleobiological data is followed by an introduction of a model, which describes the behavior of complex systems with random inter actions and uniquely leads to a double power-law observed in extinctions da ta. (C) 2001 Elsevier Science B.V. All rights reserved.