The Eve effect in the Penna model of biological ageing

In the present work we qualify and quantify the process of extinction of fa mily diversity in Penna asexual model. To qualitatively characterize irregu larity of landscapes of time series we apply the methods proposed by Peng e t al. [Phys. Rev. Lett. 70 (1993) 1343, Chaos 5 (1995) 82]. We have found t hat the fluctuations of the volume of the total population scales as 1/f no ise while the volume of a family perform the Brownian motion. This observat ion allows us to propose a model where the "Eve" effect is absent. We also consider the difference equations for which the effect is present. (C) 1999 Elsevier Science B.V. All rights reserved.