LI Duo-Fang1, CAO Tian-Guang1, GENG Jin-Peng1, QIAO Li-Hua2, GU Jian-Zhong3, ZHAN Yong1**
1Institute of Biophysics, School of Sciences, Hebei University of Technology, Tianjin 300401 2School of Basic Medicine, Heibei Medical University, Shijiazhuang 050017 3Nuclear Physics Institute, China Institute of Atomic Energy, Beijing 102413
Abstract：Species evolution is essentially a random process of interaction between biological populations and their environments. As a result, some physical parameters in evolution models are subject to statistical fluctuations. In this work, two important parameters in the Eigen model, the fitness and mutation rate, are treated as Gaussian distributed random variables simultaneously to examine the property of the error threshold. Numerical simulation results show that the error threshold in the fully random model appears as a crossover region instead of a phase transition point, and as the fluctuation strength increases the crossover region becomes smoother and smoother. Furthermore, it is shown that the randomization of the mutation rate plays a dominant role in changing the error threshold in the fully random model, which is consistent with the existing experimental data. The implication of the threshold change due to the randomization for antiviral strategies is discussed.
2015, Vol. 32 
