Mutationism and the Reproductive Struggle:A Fresh Evolutionary Synthesis beyond Neodarwinism
As the physical basis for evolution,Neodarwinism emphasized mutation within cell lineages diverging through cell division and merging through sexual fusion.Lateral gene transfer and symbiogenesis (intracellular enslavement of foreign cells and their merger into one) add important dimensions foreign to the mid-twentieth century New Synthesis.Evolution involves three processes:inheritance (via DNA replication,and membrane growth and division); mutation (accidental inherited changes in nucleic acid sequences,membrane topology and composition,or membrane-genome relationships-e.g.ploidy mutations and symbiogenesis); and the spread of mutations.Spread involves chance and inherent differences in different genotypes ability to multiply in a given environment.The latter is somewhat misleadingly anthropomorphized as ‘natural selection.Genotypic selection is not an initiating force,but an indirect consequence of novel mutation,because in a given environment inherent differences in spreadability are automatic,immediately heritable,phenotypic properties of novel mutations.Adaptation arises because of the fit or otherwise between novel phenotypes and environment,but it is mutation that generates new phenotypes,including their differential ability to spread,making it the primary cause of evolution.A sophisticated mutationism explains both adaptive organismal evolution and non-adaptive genomic evolution.Specific evolutionary explanations must also embrace organismal constraints and historical particularities.
Genome evolution megaevolution lateral gene transfer symbiogenesis membrane mutation organismal constraints anthropomorphism
Thomas Cavalier-Smith
Department of Zoology,University of Oxford,South Parks Road,Oxford,OX1 3PS,United Kingdom
国际会议
The Darwin 200 Beijing International Conference (纪念达尔文诞辰200周年国际学术会议)
北京
英文
44-59
2009-10-24（万方平台首次上网日期，不代表论文的发表时间）