Population Genetic Consequences of the Allee Effect and the Role of Offspring-Number Variation

@article{Wittmann2014PopulationGC,
  title={Population Genetic Consequences of the Allee Effect and the Role of Offspring-Number Variation},
  author={Meike J. Wittmann and Wilfried Gabriel and Dirk Metzler},
  journal={Genetics},
  year={2014},
  volume={198},
  pages={311 - 320}
}
A strong demographic Allee effect in which the expected population growth rate is negative below a certain critical population size can cause high extinction probabilities in small introduced populations. But many species are repeatedly introduced to the same location and eventually one population may overcome the Allee effect by chance. With the help of stochastic models, we investigate how much genetic diversity such successful populations harbor on average and how this depends on offspring… 

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References

SHOWING 1-10 OF 50 REFERENCES
Genetic Diversity in Introduced Populations with an Allee Effect
TLDR
Successful populations with a strong Allee effect tend to derive from larger founder population sizes and thus have a higher initial amount of genetic variation, and spend fewer generations at small population sizes where genetic drift is particularly strong, and experience more genetic drift there.
Allee effects in stochastic populations
The Allee effect, or inverse density dependence at low population sizes, could seriously impact preservation and management of biological populations. The mounting evidence for widespread Allee
Limits to genetic bottlenecks and founder events imposed by the Allee effect
TLDR
It is found that during realistic bottlenecks or founder events, >90% of H. shoshone populations in the Sierra Nevada may be resistant to significant changes in heterozygosity or genetic distance, and 70–75% of populations may lose <10% of allelic richness.
Allee effect promotes diversity in traveling waves of colonization
TLDR
It is shown that the presence of an Allee effect drastically modifies genetic diversity, both in the colonization front and behind it, and this provides insight into the dynamics of traveling wave solutions and leads to a new interpretation of the mathematical notions of pulled and pushed waves.
Allee effects in biological invasions
A Stochastic Model for Annual Reproductive Success
TLDR
A stochastic model framework for ARS is introduced and it is shown that the distributions of ARS are often multimodal and skewed, with implications for extinction risk and evolution in small populations.
Life‐History Variation Predicts the Effects of Demographic Stochasticity on Avian Population Dynamics
TLDR
It is shown that interspecific variation in demographic stochasticity can be predicted from a knowledge of the species’ position along a “slow‐fast” gradient of life‐history variation, ranging from high reproductive species with short life expectancy at one end to species that often produce a single offspring but survive well at the other end of the continuum.
The biology of small, introduced populations, with special reference to biological control
TLDR
The demographic and genetic processes at play in small populations, be they stochastic or deterministic, are reviewed and the theoretical outcomes of these different processes with respect to individual fitness, population growth rate, and establishment probability are discussed.
The evidence for Allee effects
TLDR
Although there is conclusive evidence for Allee effects due to a variety of mechanisms in natural populations of 59 animal species, it is found that existing data addressing the strength and commonness ofAllee effects across species and populations is limited; evidence for a critical density for most populations is lacking.
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