Sex enhances adaptation by unlinking beneficial from detrimental mutations in experimental yeast populations

@article{Gray2011SexEA,
  title={Sex enhances adaptation by unlinking beneficial from detrimental mutations in experimental yeast populations},
  author={Jeremy C. Gray and Matthew R. Goddard},
  journal={BMC Evolutionary Biology},
  year={2011},
  volume={12},
  pages={43 - 43}
}
BackgroundThe maintenance of sexuality is a classic problem in evolutionary biology because it is a less efficient mode of reproduction compared with asexuality; however, many organisms are sexual. Theoretical work suggests sex facilitates natural selection, and experimental data support this. However, there are fewer experimental studies that have attempted to determine the mechanisms underlying the advantage of sex. Two main classes of hypotheses have been proposed to explain its advantage… Expand
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TLDR
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TLDR
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TLDR
The results show that during evolution in benign conditions competence helps maintain genome stability but is evolutionary costly; however, during periods of stress this same conservativism enables cells to retain fitness in the face of new mutations, showing for the first time that the benefits of transformation are context dependent. Expand
Gene-flow between niches facilitates local adaptation in sexual populations.
TLDR
The effect of sex in heterogeneous environments is evaluated by manipulating gene-flow between two niches in sexual and asexual populations using steady-state microcosm experiments with yeast to find that only sex in the presence of gene- flow promotes simultaneous local adaptation to different niches. Expand
Higher rates of sex evolve during adaptation to more complex environments
TLDR
It is shown that adaptation to different environments results in varying amounts of sex and, more importantly, that higher levels of sex evolve when adapting to more complex environments, which helps explain why so many natural populations maintain such high levels ofsex. Expand
Sex and recombination purge the genome of deleterious alleles: An Individual Based Modeling Approach
TLDR
The purifying selection hypothesis, the hypothesis that recombination due to sexual reproduction helps to eliminate deleterious alleles from the genome through the selection of reduced function mutations, is corroborated. Expand
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