Let Us Not Be Unfair to Asexuals: Their Ephemerality May Be Explained by Neutral Models Without Invoking Any Evolutionary Constraints of Asexuality

Genome Evolution in Outcrossing vs. Selfing vs. Asexual Species

“…198). However, this observation may not be sufficient to support the dead-end hypothesis, and neutral models can also explain this pattern [199][200][201]. In a comprehensive and epochal phylogenetic study of several Solanaceae genera, Goldberg et al [202] went further by testing the irreversibility of transitions.…”

“…Alternatively, Janko et al [199] suggested that if asexual mutants are produced at a relatively high rate and compete with each other, this would imply a rapid turnover between clonal lineages and a young expected age for extant asexuals, without the need to invoke any fitness effect (see also refs. 200,201). Of note, this model invokes competitive exclusion among clonal lineages, but not between clonal and sexual ones-the ancestral sexual gene pool is assumed to be immune from extinction.…”

The Relationship between Sexual Selection and Sexual Conflict

“…We should, however, remind ourselves that there is another way to reproduce that achieves the same end: Asexuality removes both sexual conflict and sexual selection. It is difficult to reconcile the view that sex, with all the attendant conflict, is ultimately harmful for population fitness, with evidence that asexuality tends not to persist over evolutionary time (Neiman et al 2005; but see Janko 2014). This could be interpreted as support for the view that sexual selection is ultimately "good" for populations (e.g., Sharp and Agrawal 2013).…”

Comparing developmental stability in unisexual and bisexual rock lizards of the genusDarevskia

“…It was hypothesized that the side effects of clonal reproduction (the lack of genetic diversity together with accumulation of adverse mutations) could lead to an early extinction of a unisexual lineage, which is supported by the evidence that almost all of the recent parthenogens are of very young age (Dessauer & Cole, ; Freitas et al, ; Parker & Selander, ; Schmitz, Vences, Weitkus, Ziegler, & Böhme, ). Nevertheless, this concept has been questioned by the “neutral drift” hypothesis, which provides an alternative explanation for the young age of clones without the use of genetic decay (e.g., Janko, ; Janko, Drozd, & Eisner, ).…”