Tuyển tập các báo cáo nghiên cứu về sinh học được đăng trên tạp chí sinh học Journal of Biology đề tài: Mobilizing selection as a factor in macroevolution | Genet Sei Evol 1993 25 577-595 Elsevier INRA 577 Forum Mobilizing selection as a factor in macroevolution VA Berdnikov OE Kosterin Institute of Cytology and Genetics of the Russian Academy of Sciences Laboratory of Experimental Modelling of Evolutionary Processes Siberian Department Academician Lavrentiev Avenue 10 Novosibirsk 90 630090 Russia Received 20 November 1990 accepted 23 June 1993 Summary - We hypothesize that the probability of phyletic lineages surviving under prolonged environmental change depends on the mobility of the working structures of an organism ie on a genetically determined ability to change structures under the pressure of natural selection. If survival of phyletic lineages regularly depends on the change of the same working structure mobilizing selection should act on phyletic lineages and favour an increased mobility of this structure. The mobility of a structure increases in proportion to the number of genes governing its formation. As each gene contributes to the enhancement of the structure the trend for an increase in mobility is manifested as a macroevolutionary trend for an increase in size power and complexity of the structure. Thus the progressive development of structures is a result of the increase in their mobility. A computer simulation of the evolution of a quantitative trait controlled by a variable number of genes from a constant pool was carried out with the probability of extinction depending on the rate of favourable mutations. A gradually diminishing increase in the mean and the standard deviation of the trait accompanied by an increase in the number of genes implied was observed up to achievement of a stationary distribution. This concept is supported by the evolution of the septal suture of Ammonoidea. This process is characterized by a simultaneous increase in the mean value and standard deviation of suture complexity. This process gradually decelerated and ceased in the early Jurassic. macroevolution evolutionary .