Rethinking the (im)possible in evolution

This paper will discuss the philosophical background to evolutionary theory and present multiple counterfactuals to each of the following seven empirically unsustainable but nonetheless widespread assumptions about genomic (DNA-based) evolution: 1. All heredity transmission occurs from parent to progeny 2. Mutations are the result of inevitable replication errors 3. Mutations occur at constant low probabilities over time (= there are mutation rates) 4. Virus infection cannot induce genetic changes giving heritable resistance 5. Mutations cannot be targeted within the genome 6. Spontaneous hereditary changes are localized and limited to those of small effect 7. Cells cannot integrate DNA change with biologically useful adaptive needs. The summary take-home lesson is that we have to change from thinking of the genome as a read-only memory (ROM) that dictates the fate of the cell or organism to conceptualizing the genome as a read-write (RW) organelle modified transiently or permanently by the cell at different time scales. (C) 2012 Elsevier Ltd. All rights reserved.