Application Of Collaborative Learning Macro Of Type And Its Molecular Mechanism Of Macroevolution

The projects of genome sequencing of numerous creatures accumulated a mass of genomic data, which offered us an opportunity to study the molecular evolution of metazoan early evolution, including the muticellularity and adaptive deviation of bilaterian. To mine more information from the sequence data, more approaches should be attempt besides classic sequence alignment. Here we performed cross-species comparison in pan-eukaryotic organisms. Based on this result we introduced the macroscopic approach of synergetics, the Maximum information principle (MIP), to analyse these sequences, and discussed and formulized the hypothesis of panctuatet equiliblium and the relationship of macroevolution and microevolution. The following conclusions are obtained:1)By genomic comparison among six pan-bilaterian model species, we got the orthologue genes existing in bilaterian but absent in pan-eukaryotic unicellular organisms. These genes may be closely related to the early evolution of metazoan. We selected some most conserved genes and performed case analysis with the aim of discovering some important molecular changes incontered in the early evolution of metazoan. We founded that genes related to neurotransmitter inactivation share high and stable similarity in metazoan and absent from pan-unicellular eukaryotes. This suggests that the system of neurotransmitter inactivation probably originated with the origin of nerve system encountered the early evolution of metazoan.2)besed on above data, we introduced MIP to set up a model to examine whether the construction of coding DNA sequence (CDS) obeyed the nearly neutral theory. We formulated the evolution of CDS as a progress of maximization of neutral mutation under the constraints of natural selection, and calculated the theoretical distribution of four nucleotides in one CDS via Lagrange method. The reliability of our model can be examined by counting the average relative deviation (ARD) between theoretical value and observed value. We have done the calculation two times, both of which covered main branches of eukaryotic domain. In the second time, about 82% to 99% CDS sharing an low level of ARD<0.01 . These results showed that the process ofconstructing one functional CDS from its constituent nucleotides vit their interactions can be expressed a progress of the maximization of informational entropy of nucleotide distribution in one gene caused by randome mutation under the constraints of natural selection. That is the nearly neutral theory composing the interaction of drift and selection is still obeyed as a basical principle.3) In MIP analysis we can calculate the Lagrange multipliers for each CDS, so we can calculate the average lagrange multipliers of one taxa. This average describes the selective pressure exerting on the taxa during evolution. Previous work has showed that the Lagrange multipliers changed systematically from species to species. Here we found that, in multicellularity of animals plants and fungi, the Lagrange multipliers tended to increase. But for the progress of metazoan ealry evolution, the multipliers increased during multicellularity but decreased during the origin of bilaterian. We deduced that this unusual changes probably be related with the adaptive radiation in early evolution of bilaterian, or the Cambrian life explorison. We attempted to introduce punctuated equilibrilium hypothesis to explained and formulate the phenonmenon and described the relationship of Lagrange multipliers and evolution as increasing during cladogenetic evolution and decreasin during anagenetic evolution. The formulation can explain the changes of Lagrange multipliers during early evolution of metazoan. Further study is needed to examine its availability in other puctuated equilibrium or adaptive radiation affair.4)Within one genome, the evolution of one single gene also abides by the same mechanism and follows the mathematic model. Those genes endure higher selective pressure possess lower Lagrange multipliers, which express a higher nucleotides short range correlation. Therefore, the MIP analysis was extended from comparison among species to comparison among different organs/tissues, different development stages, different populations in one species. These results throw light on extending MIP analysis from field of macroevolution to microevolution and experimental biology fields.