On the Fractal Structure of Evolutionary Trees

Abstract

We analyse in terms of a fractal tree the time sequences of major evolutionary leaps at various scales : from the scale of the "global" tree of life (appearance of life to homeothermy), to the distinct scales of organization of clades, such as sauropod and theropod dinosaurs, North American equids, rodents, primates including hominids, and echinoderms. We also apply this type of model to the acceleration observed in the economic crisis no-crisis pattern in Western and pre-Columbian civilizations. In each case we find that these data are consistent with a log-periodic law of acceleration or deceleration, to a high level of statistical significance. Such a law is characterized by a critical epoch of convergence T c specific to the lineage under consideration. These results support a description of evolutionary trees in terms of critical phenomena.