title: On a logical difficulty in the directed mutation debate.
abstract: This paper calls attention to an overlooked logical difficulty that has impeded the directed mutation debate for over half a century. It further suggests that the random mutation hypothesis be regarded at present as a null hypothesis in evolutionary biology.
authors.affiliation: Department of Epidemiology and Biostatistics, School of Rural Public Health, Texas A&M Health Science Center, College Station, TX 77843, USA. qzheng@srph.tamhsc.edu
authors.forename: Qi
authors.initials: Q
authors.lastname: Zheng
mesh_terms: D001419:Bacteria / Q000235:genetics*; D019143:Evolution, Molecular; D014644:Genetic Variation; D009154:Mutation