Twenty-three papers by the Committee on Genetic Experimentation (COGENE) review recent advances in experimental studies on microorganisms, plants and animals.Twenty-three papers review recent advances in experimental studies on microorganisms, plants and animals. They are taken from a symposium organized at Cologne University, April 1983 by the Committee on Genetic Experimentation (COGENE), a scientific committee of the International Council of Scientific Unions.Twenty-three papers review recent advances in experimental studies on microorganisms, plants and animals. They are taken from a symposium organized at Cologne University, April 1983 by the Committee on Genetic Experimentation (COGENE), a scientific committee of the International Council of Scientific Unions.Twenty-three papers review recent advances in experimental studies on microorganisms, plants and animals. They are taken from a symposium organized at Cologne University, in April 1983 by the Committee on Genetic Experimentation (COGENE), a scientific committee of the International Council of Scientific Unions.Speakers and editors; Preface; The committe on genetic experimentation; The international council of scientific unions; The ICSU Press; Acknowledgements; Part I. Micro-Organisms: 1. Natural mechanisms of microbial evolution Werner Arber; 2. Transitory recombination between phage and plasmid genomes S. D. Ehrlich, M. Dagert, S. Romac and B. Michel; 3. Survival of plasmids in escherichia coli S. B. Levy; 4. Gene cloning and bacterial pathogenicity W. Goebel, J. Hacker, C. Hughes, S. Knapp, H. Hof, D. Muller, A. Juarez and J. Kreft; 5. Selective evolution of genes for enhanced degradation of persistent, toxic chemicals A. M. Chakrabarty, J. S. Karns, J. J. Kilbane and D. K. Chatterjee; 6. Deliberate release of microorganisms for insect control P. Luthy, H. M. Fischer and R. Hutter; Part II. Gene Expression in Plants: 7. Isolation of transposable elements in maize P. Starlinger, U. Courage-Tebbe, H. P. lƒd