Fitness dependence preserves selection for recombination across diverse mixed mating strategies

Modeling the evolution of recombination plasticity: A prospective review

“…The “failure” of both mechanisms made the problem even more intriguing since most of the existing evidence for fitness‐dependent recombination comes from diploids. However, our later numerical models suggested that, although the abandon‐ship mechanism is indeed inefficient, the recombination rate variation within the selected system does give the evolutionary advantage in diploids – but only provided at least three selected loci 94,102,103 . The reason is that the advantage of fitness‐dependent recombination can emerge only in the presence of variation in fitness among genotypes, but one should take into account only those genotypes in which recombination has any “visible” consequences (the rest are “recombination immaterial”, in terms of Otto and Barton 104 ).…”

“…Again, like in the case of ecological plasticity, the advantage of a fitness‐dependent strategy over the optimal constant one is easier to detect in a “fair” comparison – when the two strategies ensure a similar mean recombination rate in the population. However, fitness‐dependent recombination was repeatedly shown to be favored even in selection regimes where the optimal constant strategy implied no recombination, 94,102,103 which makes plasticity an important recombination‐protecting mechanism.…”

“…The models of such kind are extremely limited, although empirical evidence for recombination plasticity comes from both outcrossers and selfers (see Table 1). In a recent study, we attempted to examine the evolution of fitness‐dependent recombination under either partial clonality or partial diploid selfing 103 . It turned out that the recombination‐protecting effect of plasticity (measured as the proportion of selection regimes favoring fitness‐dependent recombination among those rejecting constant recombination) grew monotonically with the rate of clonality but reached a maximum under intermediate (low‐to‐moderate) rates of selfing, especially in the biologically realistic area of weak selection and epistasis.…”

“…They did indicate some effects of the mating system, but the mechanisms behind those effects remain elusive. For example, in the mentioned model with fitness‐dependent recombination, partial selfing emphasized the role of the additive‐by‐dominance epistatic component, 103 while in a similar model with constant recombination, Roze and Lenormand reported a central role of the dominance‐by‐dominance component 105 . A profound analysis is needed to reveal the nature of this discrepancy, which might originate from a principal difference between constant and plastic recombination, as well as from implicit peculiarities of the examined selection regimes (e.g., the model with plastic recombination was intentionally limited to the “recombination‐unfriendly” regimes, rejecting any non‐zero constant recombination).…”

Shift-inducible [transgenerational] increase in recombination rate as an evolving strategy in a periodic environment: a numerical model

“…We conduct all simulations for populations with panmixia and partial selfing, given the earlier revealed modulating effect of the mating system on the evolution of recombination [29][30][31], including plastic recombination [32].…”