Parallel genetic evolution within and between bacteriophage species of varying degrees of divergence Journal Article

Author(s): Bollback, Jonathan P; Huelsenbeck, John P
Article Title: Parallel genetic evolution within and between bacteriophage species of varying degrees of divergence
Abstract: Parallel evolution is the acquisition of identical adaptive traits in independently evolving populations. Understanding whether the genetic changes underlying adaptation to a common selective environment are parallel within and between species is interesting because it sheds light on the degree of evolutionary constraints. If parallel evolution is perfect, then the implication is that forces such as functional constraints, epistasis, and pleiotropy play an important role in shaping the outcomes of adaptive evolution. In addition, population genetic theory predicts that the probability of parallel evolution will decline with an increase in the number of adaptive solutions-if a single adaptive solution exists, then parallel evolution will be observed among highly divergent species. For this reason, it is predicted that close relatives-which likely overlap more in the details of their adaptive solutions-will show more parallel evolution. By adapting three related bacteriophage species to a novel environment we find (1) a high rate of parallel genetic evolution at orthologous nucleotide and amino acid residues within species, (2) parallel beneficial mutations do not occur in a common order in which they fix or appear in an evolving population, (3) low rates of parallel evolution and convergent evolution between species, and (4) the probability of parallel and convergent evolution between species is strongly effected by divergence.
Keywords: Species Specificity; Polymorphism, Genetic; Mutation/genetics; Genetic Variation; Base Sequence; Adaptation, Physiological/genetics; Amino Acid Substitution/genetics; Genome, Viral/genetics; Temperature; Evolution; Bacteriophages/genetics
Journal Title: Genetics
Volume: 181
Issue 1
ISSN: 0016-6731
Publisher: Genetics Society of America  
Publication Place: United States
Date Published: 2009-01-01
Start Page: 225
End Page: 234
Language: eng
DOI: 10.1534/genetics.107.085225
Open access: no
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