This study explores the impact of positive selection on the genetic composition of a Drosophila serrata population in eastern Australia through a comprehensive analysis of 110 whole genome sequences. Utilizing an advanced deep learning algorithm (partialS/HIC) and a range of inferred demographic histories, we identified that approximately 14% of the genome is directly affected by sweeps, with soft sweeps being more prevalent (10.6%) than hard sweeps (2.
View Article and Find Full Text PDFDiet elicits varied effects on longevity across a wide range of animal species where dietary discordance between an organisms' evolutionary and developmental dietary history is increasingly recognized to play a critical role in shaping lifespan. However, whether such changes, predominantly assessed in a single generation, lead to evolutionary shifts in lifespan remains unclear. In this study, we used an experimental evolution approach to test whether changes in an organisms' evolutionary and developmental dietary history, specifically carbohydrate content, causes lifespan evolution in .
View Article and Find Full Text PDFStanding genetic variation, and capacity to adapt to environment change, will ultimately depend on the fitness effects of mutations across the range of environments experienced by contemporary, panmictic, populations. We investigated how mild perturbations in diet and temperature affect mutational (co)variances of traits that evolve under climatic adaptation, and contribute to individual fitness in Drosophila serrata. We assessed egg-to-adult viability, development time and wing size of 64 lines that had diverged from one another via spontaneous mutation over 30 generations of brother-sister mating.
View Article and Find Full Text PDFAedes aegypti is the primary vector of the arboviruses dengue (DENV) and chikungunya (CHIKV). These viruses exhibit key differences in their vector interactions, the latter moving more quicky through the mosquito and triggering fewer standard antiviral pathways. As the global footprint of CHIKV continues to expand, we seek to better understand the mosquito's natural response to CHIKV-both to compare it to DENV:vector coevolutionary history and to identify potential targets in the mosquito for genetic modification.
View Article and Find Full Text PDFThe interaction of evolutionary processes to determine quantitative genetic variation has implications for contemporary and future phenotypic evolution, as well as for our ability to detect causal genetic variants. While theoretical studies have provided robust predictions to discriminate among competing models, empirical assessment of these has been limited. In particular, theory highlights the importance of pleiotropy in resolving observations of selection and mutation, but empirical investigations have typically been limited to few traits.
View Article and Find Full Text PDFMutations with conflicting fitness effects in males and females accumulate in sexual populations, reducing their adaptive capacity. Although quantitative genetic studies indicate that sexually antagonistic polymorphisms are common, their molecular basis and population genetic properties remain poorly understood. Here, we show in fruit flies how natural variation at a single gene generates sexual antagonism through phenotypic effects on cuticular hydrocarbon (CHC) traits that function as both mate signals and protectors against abiotic stress across a latitudinal gradient.
View Article and Find Full Text PDFSex differences in lifespan remain an intriguing puzzle in evolutionary biology. While explanations range from sex differences in selection to sex differences in the expression of recessive lifespan-altering mutations (via X-linkage), little consensus has been reached. One unresolved issue is the extent to which genetic influences on lifespan dimorphism are modulated by the environment.
View Article and Find Full Text PDFIn evolutionary quantitative genetics, the genetic variance-covariance matrix, , and the vector of directional selection gradients, , are key parameters for predicting multivariate selection responses and genetic constraints. Historically, investigations of and have not overlapped with those dissecting the genetic basis of quantitative traits. Thus, it remains unknown whether these parameters reflect pleiotropic effects at individual loci.
View Article and Find Full Text PDFWolbachia is currently at the forefront of global efforts to control arbovirus transmission from the vector Aedes aegypti. The use of Wolbachia relies on two phenotypes-cytoplasmic incompatibility (CI), conferred by cifA and cifB genes in prophage WO, and Wolbachia-mediated pathogen blocking (WMPB). These traits allow for local, self-sustaining reductions in transmission of dengue (DENV) following release of Wolbachia-infected A.
View Article and Find Full Text PDFis an intracellular bacterium that blocks virus replication in insects and has been introduced into the mosquito, for the biocontrol of arboviruses including dengue, Zika, and chikungunya. Despite ongoing research, the mechanism of mediated virus blocking remains unclear. We recently used experimental evolution to reveal that mediated dengue blocking could be selected upon in the host and showed evidence that strong levels of blocking could be maintained by natural selection.
View Article and Find Full Text PDFObjectives: This study proposes a physiologic assessment of left ventricular outflow tract obstruction (LVOTO) that accommodates changes in systolic flow and accounts for the dynamic neo-left ventricular outflow tract (LVOT).
Background: Patients considered for transcatheter mitral valve replacement trials often screen-fail because of the perceived risk of LVOTO. In the Intrepid Global Pilot Study, assumed risk of LVOTO was based on computed tomography estimates of the neo-LVOT area computed at end-systole.
The dengue, Zika and chikungunya viruses are transmitted by the mosquito Aedes aegypti and pose a substantial threat to global public health. Current vaccines and mosquito control strategies have limited efficacy, so novel interventions are needed. Wolbachia are bacteria that inhabit insect cells and have been found to reduce viral infection-a phenotype that is referred to as viral 'blocking'.
View Article and Find Full Text PDFOrganisms vary widely in size, from microbes weighing 0.1 pg to trees weighing thousands of megagrams - a 10-fold range similar to the difference in mass between an elephant and the Earth. Mass has a pervasive influence on biological processes, but the effect is usually non-proportional; for example, a tenfold increase in mass is typically accompanied by just a four- to sevenfold increase in metabolic rate.
View Article and Find Full Text PDFAntagonistic selection between different fitness components (e.g., survival versus fertility) or different types of individuals in a population (e.
View Article and Find Full Text PDFTransfemoral transcatheter aortic valve replacement (TF-TAVR) is mostly performed under general anesthesia (GA) in most US centers. We examined in-hospital and 30-day outcomes in patients who underwent TF-TAVR with a self-expanding bioprosthesis using local anesthesia (LA) or GA. Patients from the Transcatheter Valve Therapeutics Registry who underwent TF-TAVR from January 2014 to June 2016 with LA or GA were evaluated.
View Article and Find Full Text PDFDengue fever is the most prevalent arboviral disease globally. Dengue virus is transmitted primarily by the Aedes aegypti mosquito. One measure of the mosquito's efficiency as a vector is the extrinsic incubation period (EIP), which is the time between the ingestion of viremic blood and the emergence of virions in the saliva.
View Article and Find Full Text PDFPhilos Trans R Soc Lond B Biol Sci
October 2018
The evolution of sex-specific phenotypes is an important dimension of diversification and local adaptation. The sex-dependent regulation of gene expression is considered a key genomic mechanism facilitating sex-dependent adaptation. In many species, genes with male-biased expression evolve faster in DNA sequence and expression level than genes with female-biased or sexually monomorphic expression.
View Article and Find Full Text PDFSexual dimorphism is a substantial contributor to the diversity observed in nature, extending from elaborate traits to the expression level of individual genes. Sexual conflict and sexually antagonistic coevolution are thought to be central forces driving the dimorphism of the sexes and its diversity. We have substantial data to support this at the phenotypic level but much less at the genetic level, where distinguishing the role of conflict from other forms of sex-biased selection and from other processes is challenging.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
May 2018
Mutual mate choice occurs when males and females base mating decisions on shared traits. Despite increased awareness, the extent to which mutual choice drives phenotypic change remains poorly understood. When preferences in both sexes target the same traits, it is unclear how evolution will proceed and whether responses to sexual selection from male choice will match or oppose responses to female choice.
View Article and Find Full Text PDFHere we describe a collection of re-sequenced inbred lines of , sampled from a natural population situated deep within the species endemic distribution in Brisbane, Australia. is a member of the speciose group whose members inhabit much of south east Asia and has been well studied for aspects of climatic adaptation, sexual selection, sexual dimorphism, and mate recognition. We sequenced 110 lines that were inbred via 17-20 generations of full-sib mating at an average coverage of 23.
View Article and Find Full Text PDFVariational modules, sets of pleiotropically covarying traits, affect phenotypic evolution, and therefore are predicted to reflect functional modules, such that traits within a variational module also share a common function. Such an alignment of function and pleiotropy is expected to facilitate adaptation by reducing the deleterious effects of mutations, and by allowing coordinated evolution of functionally related sets of traits. Here, we adopt a high-dimensional quantitative genetic approach using a large number of gene expression traits in to test whether functional grouping, defined by gene ontology (GO terms), predicts variational modules.
View Article and Find Full Text PDFBackground: The mosquito vector Aedes aegypti is responsible for transmitting a range of arboviruses including dengue (DENV) and Zika (ZIKV). The global reach of these viruses is increasing due to an expansion of the mosquito's geographic range and increasing urbanization and human travel. Vector control remains the primary means for limiting these diseases.
View Article and Find Full Text PDFBackground: Transcatheter mitral valve replacement (TMVR) is a potential therapy for patients with symptomatic, severe mitral regurgitation (MR). The feasibility of this therapy remains to be defined.
Objectives: The authors report their early experience with TMVR using a new valve system.
Objectives: The authors sought to compare the outcomes of commercial transcatheter aortic valve replacement (TAVR) with the repositionable Evolut R platform to those observed with the CoreValve device in the Society of Thoracic Surgeons (STS)/American College of Cardiology (ACC) Transcatheter Valve Therapy (TVT) Registry.
Background: TAVR continues to evolve, with rapid adoption of iterative changes for commercial practice. Insight into the outcomes of this adoption is needed.
A proposed benefit to sexual selection is that it promotes purging of deleterious mutations from populations. For this benefit to be realized, sexual selection, which is usually stronger on males, must purge mutations deleterious to both sexes. Here, we experimentally test the hypothesis that sexual selection on males purges deleterious mutations that affect both male and female fitness.
View Article and Find Full Text PDF