9. More precisely, Simpson claimed that a mutation in a poorly-adapted organism or living in a changing environment has greater chance to be advantageous than a mutation occurring in a well-adapted organism or situated in a stable environment. But this point is controversial and ignores the complexity of each particular situation. For Simpson, the adaptive value of a genetic mutation simply depends on the adaptedness of the organism concerned to its environment. However, it is also relative to other factors such as the kind of modification at the level of the nucleotide sequence, the genomic context where it occurs, and the effect of the genetic modification at the phenotypic level.

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