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SEX VS ASEXUALITY. "Many models explaining the advantage of sexual reproduction over asexuality have been proposed, including the purging of deleterious mutations, adaptation, host–parasite co-evolution, random genetic drift, and pluralistic models combining some or all of the above." http://onlinelibrary.wiley.com/doi/10.1002/ece3.1516/full View in LinkedIn

COMBINED ADVANTAGES. "In general, sex seems to allow superior responses to rapid challenges, both internal and external. Indeed, there is no consensus on a single major advantage for sex, and prevailing opinion is shifting toward a combination of advantages. That sex creates genetic variation, repairs DNA breaks, restores methylation patterns, and prevents accumulation of disadvantageous mutations is well accepted." https://lnkd.in/deZ8DED View in LinkedIn

"THE BENEFITS of eukaryotic meiotic sex are mostly discussed under the headings good, bad, and ugly: good, it generates genetic diversity in which rapid new combinations bring together beneficial mutations; bad, it purges the slow accumulation of slightly harmful mutations, i.e., it counters Muller’s ratchet; ugly, it is necessary for the arms race with rapidly changing parasites, the well-known Red Queen hypothesis." https://lnkd.in/deZ8DED View in LinkedIn

BASIC DOGMAS. "For more than a century the basic tenets for the advantages of sexual reproduction have been that it can serve to (i) generate progeny with a diversity of novel genotypes and (ii) purge the genome of deleterious mutations, such as transposable elements, which otherwise would accumulate inexorably via Muller’s Ratchet to degrade the integrity of the genome." http://www.mycologia.org/content/105/1/1.full View in LinkedIn

COST-BENEFIT RATIO. "Most higher eukaryotes engage in sexual reproduction, at least part of the time." http://onlinelibrary.wiley.com/doi/10.1002/ece3.1516/full View in LinkedIn

BENEFITS OF SEXUAL REPRODUCTION. "Given the ubiquity of sexual reproduction, combined with the fact that the few known truly asexual lineages appear to be of relatively recent origin and therefore may be doomed to more rapid extinction, it is expected that sex must confer benefits." http://www.mycologia.org/content/105/1/1.full View in LinkedIn

SPECIES AS UNIT OF SELECTION. "However, despite numerous experimental studies, such pressures in favor of sexual lineages have never been demonstrated. It would thus be a selection at the species level: a selection for species unable to lose sex because of constraints, and not a short-term advantage of sex." https://lnkd.in/dV7ZdGm View in LinkedIn

THE FECUNDITY OFFSET. The conundrum for facultatively sexual organisms: “Why engage in sex if very few of your progeny might even attain the well adapted genotype of either parent? One way to obviate this cost is to have very many progeny, such that at least one approximates the fitness of the most fit parent." http://www.mycologia.org/content/105/1/1.full View in LinkedIn

ALLELE INVASION. "We demonstrate that obligate sex can evolve in finite diploid populations in the presence of sexual selection, with or without a long-term advantage. We find a parameter range allowing the invasion of a rare obligate allele into a facultative population. The invasion is more likely to occur when mutation rate is high, the cost of sex is low, sexual selection is strong, and the facultative individuals rarely reproduce sexually. Sexual selection is critical to the results." http://onlinelibrary.wiley.com/doi/10.1002/ece3.1516/full View in LinkedIn

RISKS OF RESHUFFLING. "One of the lesser appreciated but well established costs of sexual reproduction is that it breaks apart well adapted genomic configurations that have run the gauntlet of adaptive Darwinian selection." http://www.mycologia.org/content/105/1/1.full View in LinkedIn