Search results for "Fitness effects"
showing 6 items of 6 documents
Sex ratio at mating does not modulate age fitness effects in Drosophila melanogaster
2019
Abstract Understanding the effects of male and female age on reproductive success is vital to explain the evolution of life history traits and sex‐specific aging. A general prediction is that pre‐/postmeiotic aging processes will lead to a decline in the pre‐ and postcopulatory abilities of both males and females. However, in as much the sexes have different strategies to optimize their fitness, the decline of reproductive success late in life can be modulated by social context, such as sex ratio, in a sex‐specific manner. In this study, we used Drosophila melanogaster to investigate whether sex ratio at mating modulates age effects on male and female reproductive success. As expected, male…
Risk of inbreeding : problem of mate choice and fitness effects?
2016
Mating with close kin may cause inbreeding depression with negative consequences to offspring and local populations. There exist mechanisms like kin-recognition or sex-specific dispersal to avoid mating with kin. In fluctuating population densities, like in many small mammals, both very low and very high densities provide conditions for inbreeding, if kin males are prone to stay in their natal area. Females are choosy and male dominance is thought to be the key feature when selecting mating partners. The aim of this study was to test the possible discrepancy in mate choice and negative fitness effects of inbreeding in two experiments, one in the laboratory and one in field enclosures. We as…
Epigenetic mutations can both help and hinder adaptive evolution.
2015
Epigenetic variation is being integrated into our understanding of adaptation, yet we lack models on how epigenetic mutations affect evolution that includes de novo genetic change. We model the effects of epigenetic mutations on the dynamics and endpoints of adaptive walks—a process where a series of beneficial mutations move a population towards a fitness optimum. We use an individual-based model of an asexual population, where mutational effects are drawn from Fisher's geometric model. We find cases where epigenetic mutations speed adaptation or result in populations with higher fitness. However, we also find cases where they slow adaptation or result in populations with lower fitness. Th…
EFFECT OF DELETERIOUS MUTATION-ACCUMULATION ON THE FITNESS OF RNA BACTERIOPHAGE MS2
2000
RNA viruses show the highest mutation rate in nature. It has been extensively demonstrated that, in the absence of purifying selection, RNA viruses accumulate deleterious mutations at a high rate. However, the parameters describing this accumulation are, in general, poorly understood. The present study reports evidences for fitness declines by the accumulation of deleterious mutations in the bacteriophage MS2. We estimated the rate of fitness decline to be as high as 16% per bottleneck transfer. In addition, our results agree with an additive model of fitness effects.
Globally defining the effects of mutations in a picornavirus capsid
2021
The capsids of non-enveloped viruses are highly multimeric and multifunctional protein assemblies that play key roles in viral biology and pathogenesis. Despite their importance, a comprehensive understanding of how mutations affect viral fitness across different structural and functional attributes of the capsid is lacking. To address this limitation, we globally define the effects of mutations across the capsid of a human picornavirus. Using this resource, we identify structural and sequence determinants that accurately predict mutational fitness effects, refine evolutionary analyses, and define the sequence specificity of key capsid-encoded motifs. Furthermore, capitalizing on the derive…
The distribution of fitness effects caused by single-nucleotide substitutions in an RNA virus.
2004
6 pages, 3 figures.-- PMID: 15159545 [PubMed].-- PMCID: PMC420405.-- Supporting information (Table 3: Relevant information about each single-nucleotide substation mutant created) available at: http://www.pnas.org/content/101/22/8396/suppl/DC1