THE GENETIC INTERPRETATION OF INBREEDING DEPRESSION AND OUTBREEDING DEPRESSION

@article{Lynch1991THEGI,
  title={THE GENETIC INTERPRETATION OF INBREEDING DEPRESSION AND OUTBREEDING DEPRESSION},
  author={Michael Lynch},
  journal={Evolution},
  year={1991},
  volume={45}
}
  • M. Lynch
  • Published 1991
  • Biology, Medicine
  • Evolution
Inbreeding with close relatives and outbreeding with members of distant populations can both result in deleterious shifts in the means of fitness‐related characters, most likely for very different reasons. Such processes often occur simultaneously and have important implications for the evolution of mating systems, dispersal strategies, and speciation. They are also relevant to the design of breeding strategies for captive populations of endangered species. A general expression is presented for… Expand
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References

SHOWING 1-10 OF 62 REFERENCES
THE EVOLUTION OF SELF‐FERTILIZATION AND INBREEDING DEPRESSION IN PLANTS. I. GENETIC MODELS
  • R. Lande, D. Schemske
  • Biology, Medicine
  • Evolution; international journal of organic evolution
  • 1985
TLDR
Genetic models are constructed which allow inbreeding depression to change with the mean selfing rate in a population by incorporating both mutation to recessive and partially dominant lethal and sublethal alleles at many loci and mutation in quantitative characters under stabilizing selection. Expand
INBREEDING DEPRESSION AND ITS EVOLUTIONARY CONSEQUENCES
TLDR
The evidence that the evolution of breeding systems of animals and plants has been significantly influenced by the occurrence of inbreeding depression is reviewed, and the contemporary genetic theory of inmarriage depression and heterosis and the experimental data concerning the strength of in breeding depression are considered. Expand
Pollen dispersal and optimal outcrossing in Delphinium nelsoni
TLDR
It is suggested that outbreeding depression will often occur on a much finer scale than previously recognised, especially in plants subject to restricted pollen and seed dispersal, and a short outcrossing distance is optimal for Delphinium nelsoni Greene. Expand
Design and analysis of experiments on random drift and inbreeding depression.
TLDR
In general, it appears that the authors can best understand the response of populations to inbreeding and finite population size by studying a very large number of self-fertilizing or full-sib mated lines in parallel with one or more stable control populations. Expand
THE EVOLUTION OF SELF‐FERTILIZATION AND INBREEDING DEPRESSION IN PLANTS. II. EMPIRICAL OBSERVATIONS
  • D. Schemske, R. Lande
  • Biology, Medicine
  • Evolution; international journal of organic evolution
  • 1985
A bimodal distribution of outcrossing rates was observed for natural plant populations, with more primarily selfing and primarily outcrossing species, and fewer species with intermediate outcrossingExpand
Estimates of Lethal Equivalents and the Cost of Inbreeding in Mammals
TLDR
The cost of inbreeding in natural populations of mammals are unknown despite their theoretical importance in genetic and sociobiological models and practical applications in conservation biology, and the regression of juvenile survival on the inbreeding coefficient using pedigrees of 40 captive mammalian populations belonging to 38 species is estimated. Expand
The Relationship of Heterosis and Genetic Divergence in Maize.
TLDR
The issue in this report is whether or not heterosis in maize continues to in- crease at higher levels of diversity. Expand
Factors eliminating inbreeding depression in a captive herd of speke's gazelle (Gazella spekei)
TLDR
It is concluded that inbreeding depressions can be rapidly and effectively reduced by an appropriate breeding program, and hence an inbreeding depression does not constitute an insurmountable barrier to the long-term maintenance of a species in which inbreeding cannot be avoided. Expand
Optimal outcrossing in Ipomopsis aggregata : Seed set and offspring fitness
TLDR
The possibility that differences in seed set might in part reflect maternal mate discrimination is discussed and the desirability of measuring offspring fitness under natural conditions in assessing outcrossing effects is emphasized. Expand
INBREEDING DEPRESSION AND PROXIMITY‐DEPENDENT CROSSING SUCCESS IN PHLOX DRUMMONDII
  • D. Levin
  • Biology, Medicine
  • Evolution; international journal of organic evolution
  • 1984
TLDR
The magnitude of viability depression from inbreeding in plants is dependent upon genetic and environmental variables, and species whose genetic systems are adapted to relatively high levels of homozygosity are likely to show the least viability depression with inbreeding. Expand
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