Clonal interference and Mullerʼs ratchet in spatial habitats

@article{Otwinowski2014ClonalIA,
  title={Clonal interference and Mullerʼs ratchet in spatial habitats},
  author={Jakub Otwinowski and Joachim H A Krug},
  journal={Physical Biology},
  year={2014},
  volume={11}
}
Competition between independently arising beneficial mutations is enhanced in spatial populations due to the linear rather than exponential growth of clones. Recent theoretical studies have pointed out that the resulting fitness dynamics is analogous to a surface growth process, where new layers nucleate and spread stochastically, leading to the build up of scale-invariant roughness. This scenario differs qualitatively from the standard view of adaptation in that the speed of adaptation becomes… 
Environmental disorder can tip the population genetics of range expansions
TLDR
It is argued here that the fluctuations at the range edge are susceptible to small-scale environmental heterogeneities that may have a strong effect on the evolutionary dynamics of the expanding population.
Mutant Evolution in Spatially Structured and Fragmented Expanding Populations
TLDR
This work provides an intuitive explanation for the complex dependence of disadvantageous mutant evolution on spatial restriction, which relies on desynchronized dynamics in different locations/patches, and plays out differently depending on whether the disadvantage is due to a lower division rate or a higher death rate.
Critical fitness collapse in three-dimensional spatial population genetics
TLDR
This work considers population fitness collapse in 3D range expansions with both inflating and fixed-size frontiers, and finds that the onset of fitness collapse obeys different scaling laws, and that competition between species at the frontier leads to a deviation from directed percolation scaling.
Spatial structure affects evolutionary dynamics and drives genomic diversity in experimental populations of Pseudomonas fluorescens
TLDR
Test results confirm important general impacts of spatial structure on evolutionary dynamics at both the phenotypic and genomic level in replicate populations of Pseudomonas fluorescens.
Collective motion conceals fitness differences in crowded cellular populations
TLDR
This work suggests that, in crowded populations, cells cooperate with surrounding neighbours through inevitable mechanical interactions, and this effect has to be considered when predicting evolutionary outcomes, such as the emergence of drug resistance or cancer evolution.
Deterministic approximation for population dynamics in the presence of advantageous mutants
TLDR
A deterministic approximation to a spatial stochastic birth-death process in the presence of two types: the less advantageous resident type and a more advantageous mutant, which is a power law of division and death rates of the two types.
The role of standing variation in geographic convergent adaptation
TLDR
The results suggest that much of adaptation may be geographically local even when selection pressures are homogeneous, and argue that caution must be exercised when arguing that strongly geographically restricted alleles are necessarily the outcome of local adaptation.
The Role of Standing Variation in Geographic Convergent Adaptation*
TLDR
This article explores how standing genetic variation contributes to convergent genetic responses in a geographically spread population, and derives the geographic scale over which an allele dominates and the proportion of adaptive alleles that arise from standing variation.
Shape of population interfaces as an indicator of mutational instability in coexisting cell populations.
TLDR
It is found that the shape of the population interface serves as an indicator for the evolutionary dynamics within the heterogeneous population, and invasion front undulations become enhanced when the invading population is near a mutational meltdown transition or when the surrounding ‘bystander’ population is barely able to reinvade the mutating population.
Spatially Constrained Growth Enhances Conversional Meltdown.