The evolutionary processes governing variability within genomic regions of low recombination have been the focus many studies. Here, I investigate statistical properties a measure intrlocus genetic associations under assumption that mutations are selectively neutral and sites completely linked. This measure, denoted ZnS, is based on squared correlation allelic identity at pairs polymorphic sites. Upper bounds for ZnS determined by simulations. Various deviations from model, including several...

We describe a statistical framework for QTL mapping using bulk segregant analysis (BSA) based on high throughput, short-read sequencing. Our proposed approach is smoothed version of the standard statistic, and takes into account variation in allele frequency estimates due to sampling segregants form bulks as well introduced during sequencing bulks. Using simulation, we explore impact key experimental variables such size coverage ability detect QTLs. Counterintuitively, find that relatively...

Adaptive modifications of heteromeric proteins may involve genetically based changes in single subunit polypeptides or parallel multiple genes that encode distinct, interacting subunits. Here we investigate these possibilities by conducting a combined evolutionary and functional analysis duplicated globin natural populations deer mice ( Peromyscus maniculatus ) are adapted to different elevational zones. A multilocus nucleotide polymorphism linkage disequilibrium revealed high-altitude...

Anthropogenic perturbations including habitat loss and emerging disease are changing pollinator communities generating novel selection pressures on plant populations. Disruption of plant-pollinator relationships is predicted to cause mating system evolution, although this process has not been directly observed. This study demonstrates the immediate evolutionary effects within experimental populations a predominately outcrossing wildflower. Initially equivalent evolved for five generations...

See also the Commentary by Richards and Wendel

Fluctuating selection in nature Natural environmental variation can lead to individuals within a species experiencing different selective parameters. Seep monkeyflower ( Mimulus guttatus ) populations are constrained by local moisture availability and the onset of summer drought. This results tradeoff between amount seed set, which is determined plant size, timing reproduction. Troth et al. sequenced phenotyped 187 M. plants identified genetic variants associated with flower size rapid...

Abstract Reinforcement is an increase in premating reproductive isolation between taxa resulting from selection against hybrids. We present a model of reinforcement with novel type on female mating behavior. Previous models have focused the divergence preferences nascent species. suggest that level discrimination can yield without further either male characters or preferences. This indicates viable mechanism for and may allow speciation under less stringent conditions than preference. also...

Abstract Results from norm of reaction studies and selection experiments indicate that elevated CO 2 will act as a selective agent on natural plant populations, especially for C 3 species are most sensitive to changes in atmospheric concentration. Evolutionary responses may alter physiology, development rate, growth, reproduction ways cannot be predicted single generation studies. Moreover, ecological evolutionary communities have range consequences at higher spatial scales cause substantial...

Natural selection operates throughout the life cycle of an organism. Correlative studies typically fail to consider effects viability prior trait expression. A 3-year field experiment on wildflower Mimulus guttatus demonstrates that this unmeasured component can be very strong. As in previous studies, we find fecundity is positively related flower size. However, survival flowering much lower large-flowered genotypes than small-flowered genotypes. Aggregating and fecundity, lifetime fitness...

Abstract Why do populations remain genetically variable despite strong continuous natural selection? Mutation reconstitutes variation eliminated by selection and genetic drift, but theoretical experimental studies each suggest that mutation‐selection balance insufficient to explain extant in most complex traits. The alternative hypothesis of balancing selection, wherein maintains variation, is an aggregate multiple mechanisms (spatial temporal heterogeneity frequency‐dependent antagonistic...

Female meiotic drive, in which chromosomal variants preferentially segregate to the egg pole during asymmetric female meiosis, is a theoretically pervasive but still mysterious form of selfish evolution. Like other genetic elements, driving chromosomes may be maintained as balanced polymorphisms by pleiotropic or linked fitness costs. A centromere-associated driver (D) with ∼58:42 female-specific transmission advantage occurs at intermediate frequency (32–40%) Iron Mountain population yellow...

Insect herbivory is a major driving force of plant evolution. Phenotypic plasticity and developmental variation provide means for plants to cope with variable herbivory. We characterized the genetics phenotypic in trichome density, putative defensive trait Mimulus guttatus (yellow monkeyflower). Our results are evaluated relation optimal defense theory, which provides testable predictions plastic patterns traits. found that both stage simulated insect damage affected production, but...

Across western North America, Mimulus guttatus exists as many local populations adapted to site-specific environmental challenges. Gene flow between locally will affect genetic diversity both within demes and across the larger metapopulation. Here, we analyse 34 whole-genome sequences from intensively studied Iron Mountain population (IM) in conjunction with 22 individuals sampled America. Three striking features of these data address hypotheses about migration selection a population. First,...

We develop analytical and simulation tools for evolve-and-resequencing experiments apply them to a new study of rapid evolution in

In the formation of species, adaptation by natural selection generates distinct combinations traits that function well together. The maintenance adaptive trait in face gene flow depends on strength and nature acting underlying genetic loci. Floral pollination syndromes exemplify evolution for particular pollinators. North American wildflower genus Penstemon displays remarkable floral syndrome convergence, with at least 20 separate lineages have evolved from ancestral bee (wide blue-purple...

The mean diameter of viable pollen grains is approximately 13 μm greater than the inviable in Mimulus guttatus . We show that this difference large enough to be detected by particle counters and these machines can used obtain a rapid estimate viability. While requiring separate calibration, size‐based statistic also strongly correlated with viability Collinsia verna These results suggest statistics derived from size distribution may provide an alternative more labor‐intensive methods for...

Classical models studying the evolution of self-fertilization in plants conclude that only complete selfing and outcrossing are evolutionarily stable. In contrast with this prediction, 42% seed-plant species reported to have rates between 0.2 0.8. We propose many previous fail predict intermediate because they do not allow for functional relationships among three components reproductive fitness: self-fertilized ovules, outcrossed ovules sired by successful pollen export. Because optimal...

Abstract An important goal of population genetics is to elucidate the effects natural selection on patterns DNA sequence variation. Here we report results a study assess joint selection, recombination, and gene flow in shaping nucleotide variation at genes involved local adaptation. We first describe new summary statistic, Zg, that measures between-sample component linkage disequilibrium (LD). then multilocus survey diversity LD between high- low-altitude populations deer mice, Peromyscus...

The influence of genetic interactions (epistasis) on the variance quantitative traits is a major unresolved problem relevant to medical, agricultural, and evolutionary genetics. additive component typically high proportion total in traits, despite that underlying genes must interact determine phenotype. This study estimates direct interaction effects for 11 pairs Quantitative Trait Loci (QTLs) affecting floral within single population Mimulus guttatus. With all 9 genotypes each QTL pair, we...

Abstract Polymorphic chromosomal rearrangements can bind hundreds of genes into single genetic loci with diverse effects. Rearrangements are often associated local adaptation and speciation may also be an important component variation within populations. We genetically phenotypically characterize a segregating inversion (inv6) in the Iron Mountain (IM) population Mimulus guttatus (yellow monkeyflower). initially mapped inv6 as region recombination suppression three F2 populations resulting...

The level and pattern of gene expression is increasingly recognized as a principal determinant plant phenotypes thus fitness. estimation natural selection on the transcriptome an emerging research discipline. We here review recent progress consider challenges posed by high dimensionality for multiple regression methods routinely used to characterize in field experiments. several different methods, including classical multivariate statistical approaches, regularized regression, latent factor...

A suggestion that limited migration, i.e., population viscosity, should favor the evolution of altruism has been challenged by recent kin selection models explicitly incorporating restricted migration. It is demonstrated these compound two distinct elements structure, spatial-genotypic variation and density regulation. These characteristics are often determined biological processes. While they may be linked under certain circumstances, this not invariably true. simple modification migration...