On the evolutionary stability of the female-biased sex ratio in the wood lemming (Myopus schisticolor): the effect of inbreeding

Smith, J. Andrew C.; Stenseth, N. C.

doi:10.1038/hdy.1978.89

Cited by 47 publications

(18 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Fredga et al (1993) have noted that the sex ratio seems to vary depending on the time of the year or on the phase of the population cycle. First it was hypothesized that the female biased sex ratio is maintained by inbreeding, especially when the population density is low (Maynard Smith and Stenseth, 1978;Stenseth, 1978). However, isozyme studies showed that wood lemming populations are generally in HardyWeinberg equilibrium (HWE) (Fedorov, 1990(Fedorov, , 1991(Fedorov, , 1993Gileva and Fedorov, 1991;Fredga et al, 1993) indicating random mating.…”

Section: Introductionmentioning

confidence: 99%

Long-term stability of allozyme frequencies in a wood lemming, Myopus schisticolor, population with a biased sex ratio and density fluctuations

Vuorinen

Eskelinen

2005

Heredity

View full text Add to dashboard Cite

Wood lemming (Myopus schisticolor) populations are characterized by female biased sex ratios and cyclic variations in population size. Both of these characteristics are assumed to reduce genetic variation and thus affect the evolutionary adaptation of the species. We addressed these questions by studying the genetic structure of a wood lemming population from eastern Finland by isozyme markers during a 21-year period, which corresponds to 40-50 generations. Contingency tests showed that genotypic proportions conformed to Hardy-Weinberg equilibrium in each of the four sampling years. Among the temporal replicates, allele frequencies differed most by 0.14 and were not significant. Genetic variation was also stable and fairly high with a mean observed heterozygosity of H ¼ 0.057. Variability in the Heinävesi population was higher than previously reported in wood lemming. The difference was mainly caused by variation at a phosphoglucomutase locus that was monomorphic in earlier studies. Significant linkage disequilibrium was observed in three of the comparisons but the disequilibrium did not appear consistently in all years. This pattern was also evidenced by the variance components, which indicated that selection favoured for specific allele pairs only in few subsamples. Heredity (2005) 94, 443-447.

show abstract

Section: Introductionmentioning

confidence: 99%

Long-term stability of allozyme frequencies in a wood lemming, Myopus schisticolor, population with a biased sex ratio and density fluctuations

Vuorinen

Eskelinen

2005

Heredity

View full text Add to dashboard Cite

show abstract

“…For example, in the wood lemming Myopus schisticolor, a mutant X is present besides the regular one, and this new X suppresses the male-determining action of the Y. The resulting female bias in the population has been proposed to be beneficial under the condition of recurrent inbreeding of this species (19).…”

Section: Sex Chromosomes Of Xenopus Tropicalismentioning

confidence: 99%

Sex determination by multiple sex chromosomes in Xenopus tropicalis

Schartl

2015

Proc. Natl. Acad. Sci. U.S.A.

View full text Add to dashboard Cite

“…Each one of these factors was put forward to explain biased sex ratios in partial sib-mating populations and more generally in structured populations (Hamilton 1967;Maynard Smith and Stenseth 1978;see, e.g., Karlin and Lessard 1986 and references therein). Our results enlighten the exact role of these factors in the change of allele frequencies at least in partial full-sib mating populations.…”

Section: Interpretation and Discussionmentioning

confidence: 99%

Kin Selection Is Implicated in Partial Sib-Mating Populations With Constant Viability Differences Before Mating

Lessard

2005

Genetics

View full text Add to dashboard Cite

The change in the frequency of a rare mutant allele under constant sex-differentiated viability selection in an infinite, partial full-sib mating population is studied. The diplo-diploid and haplo-diploid polygynous models are considered with a Poisson distribution for the number of offspring produced by every mated female. Reproduction is followed by weak selection among the offspring and then mating to form the next generation. It is shown that the rate of change with respect to the frequency of the mutant allele and the intensity of selection can be expressed in terms of costs or benefits of substituting the mutant type for the wild type, which correspond to average excesses in viability in females and males, multiplied by coefficients of relatedness to the individuals affected by such a substitution and reproductive values associated to the sexes of these individuals. This reveals hidden interactions between mated individuals and between males for mating, the former having positive effects on the reproductive success of related individuals and the latter having negative effects. Such interactions are the result of reproductive constraints when a fixed proportion of females must mate with a male sib and all females are fertilized as long as one mate is available. However, they affect the change in allele frequency because there is inbreeding or relatedness between mates and more generally relatedness between interacting individuals. Surprisingly, the effects of these interactions cancel out in a diploid population when the number of offspring is large enough so that the possibility for a female to have no male sib to mate with can be neglected and the viability differences are the same in both sexes. S TUDYING the change in the frequency of an allele at one locus in a partial sib-mating population under weak viability selection, Pollak (1995) found a discrepancy with the formula that is entailed by Wright's (1942) adaptive topography in the case of a partially inbred population that is close to equilibrium: the change obtained was actually given by Wright's formula times one plus the correlation coefficient between the frequencies of the allele in mated individuals. Caballero (1996) pointed out that Wright's formula may not apply to Pollak's model for the reason that it is a kind of fertility model with selection occurring after mating and showed that the formula should be fully valid if viability selection takes place before mating. Actually, with selection after mating, there is a kin selection effect (Hamilton 1964) due to the fact that mated individuals are related to one another and their reproductive success depends on the survival of both. This is the case even without interactions between kin affecting viability. The effects of such interactions before or after mating with small differences among phenotypes or fitnesses were studied still recently (Lessard and Rocheleau 2003, 2004) and led to the introduction of generalized coefficients of relatedness conditional on the inbreeding state of the...

show abstract

On the evolutionary stability of the female-biased sex ratio in the wood lemming (Myopus schisticolor): the effect of inbreeding

Cited by 47 publications

References 13 publications

Long-term stability of allozyme frequencies in a wood lemming, Myopus schisticolor, population with a biased sex ratio and density fluctuations

Long-term stability of allozyme frequencies in a wood lemming, Myopus schisticolor, population with a biased sex ratio and density fluctuations

Sex determination by multiple sex chromosomes in Xenopus tropicalis

Kin Selection Is Implicated in Partial Sib-Mating Populations With Constant Viability Differences Before Mating

Contact Info

Product

Resources

About