Scaling in nature: from DNA through heartbeats to weather

The purpose of this report is to describe some recent progress in applying scaling concepts to various systems in nature. We review several systems ch aracterized by scaling laws such as DNA sequences, heartbeat rates and weat her variations. We discuss the finding that the exponent a quantifying the scaling in DNA in smaller for coding than for noncoding sequences. We also discuss the application of fractal scaling analysis to the dynamics of hear tbeat regulation, and report the recent finding that the scaling exponent c c is smaller during sleep periods compared to wake periods. We also discuss the recent findings that suggest a universal scaling exponent characterizi ng the weather fluctuations. (C) 1999 Elsevier Science B.V. All rights rese rved.