4 research outputs found
Distribution of Genotypes Within and Among \u3cem\u3eTaeniatherum caput-medusae\u3c/em\u3e (Poaceae) Populations from Eastern Washington: Assessment of an Invasion at a Local Scale
Multiple introductions from many source populations can increase the chance of introducing preadapted genotypes, increase standing genetic variation, and increase the likelihood of adaptive evolution, all of which might contribute to invasion. Taeniatherum caput-medusae is an annual, highly self-pollinating grass that is invasive in the western United States. Through previous genetic analysis, five multilocus genotypes (MLG) were detected in the relatively small geographic area of eastern Washington, which suggests that multiple introductions have occurred in this region. Fifty-seven populations of T. caput-medusae from eastern Washington were assessed at 23 loci using starch gel electrophoresis. Based on these data, a sixth MLG was detected in the study area. The Steptoe Butte genotype, which was first introduced in 1901, has the largest range of the six genotypes and is creating polymorphic populations where it comes into contact with other genotypes. Founder effects appear to have reduced genetic diversity within and among populations from eastern Washington in comparison to native populations. The results of this study contribute to our understanding of the invasion process at a local spatial scale by reconstructing the introduction and range expansion of T. caput-medusae in eastern Washington
Rationale, design and methods for a randomised and controlled trial to evaluate "Animal Fun" - a program designed to enhance physical and mental health in young children
Background: Children with poor motor ability have been found to engage less in physical activities than other children, and a lack of physical activity has been linked to problems such as obesity, lowered bone mineral density and cardiovascular risk factors. Furthermore, if children are confident with their fine and gross motor skills, they are more likely to engage in physical activities such as sports, crafts, dancing and other physical activity programs outside of the school curriculum which are important activities for psychosocial development. The primary objective of this project is to comprehensively evaluate a whole of class physical activity program called Animal Fun designed for Pre-Primary children. This program was designed to improve the child's movement skills, both fine and gross, and their perceptions of their movement ability, promote appropriate social skills and improve social-emotional development. Methods: The proposed randomized and controlled trial uses a multivariate nested cohort design to examine the physical (motor coordination) and psychosocial (self perceptions, anxiety, social competence) outcomes of the program. The Animal Fun program is a teacher delivered universal program incorporating animal actions to facilitate motor skill and social skill acquisition and practice. Pre-intervention scores on motor and psychosocial variables for six control schools and six intervention schools will be compared with post-intervention scores (end of Pre-Primary year) and scores taken 12 months later after the children's transition to primary school Year 1. 520 children aged 4.5 to 6 years will be recruited and it is anticipated that 360 children will be retained to the 1 year follow-up. There will be equal numbers of boys and girls.Discussion: If this program is found to improve the child's motor and psychosocial skills, this will assist in the child's transition into the first year of school. As a result of these changes, it is anticipated that children will have greater enjoyment participating in physical activities which will further promote long term physical and mental health
Mating System Analysis of Native Populations of \u3cem\u3eTaeniatherum caput-medusae\u3c/em\u3e (Medusahead): Potential for Post-Introduction Evolution During Biological Invasions
Taeniatherum caput-medusae (medusahead) is a highly invasive grass in the Western United States (U.S.). Using enzyme electrophoresis, I determined the mating system of native populations using two approaches: the Inbreeding Coefficient (F) method and progeny array analysis. These results were compared with data for invasive populations to determine whether an evolution of mating system is associated with this invasion. Previous data indicated that 10 invasive populations were 99.8% self-pollinating, with a 0.2% outcrossing rate. Both approaches I used were in agreement, and indicate that the 10 native populations I analyzed are 100.0% self-pollinating (and 0.0% outcrossing). These data indicate an extremely high self-pollination rate for both native and invasive populations, and do not suggest a mating system shift has occurred. Rather, high levels of self-pollination within native populations suggest that this highly selfing mating system may be a pre-adaptation contributing to the invasion of T. caput-medusae in the Western U.S
Data from: Selfing ability and drift load evolve with range expansion
Colonization at expanding range edges often involves few founders, reducing effective population size. This process can promote the evolution of self-fertilization, but implicating historical processes as drivers of trait evolution is often difficult and requires an explicit model of biogeographic history. In plants, contemporary limits to outcrossing are often invoked as evolutionary drivers of self-fertilization, but historical expansions may shape mating system diversity, with leading-edge populations evolving elevated selfing ability. In a widespread plant, Campanula americana, we identified a glacial refugium in the southern Appalachian Mountains from spatial patterns of genetic drift among 24 populations. Populations farther from this refugium have smaller effective sizes and fewer rare alleles. They also displayed elevated heterosis in among-population crosses, reflecting the accumulation of deleterious mutations during range expansion. While populations with elevated heterosis had reduced segregating mutation load, the magnitude of inbreeding depression lacked geographic pattern. The ability to self-fertilize was strongly positively correlated with the distance from the refugium and mutation accumulationâa pattern that contrasts sharply with contemporary mate and pollinator limitation. In this and other species, diversity in sexual systems may reflect the legacy of evolution in small, colonizing populations, with little or no relation to the ecology of modern populations.,Phenotypic data for f inbreeding depression and drift loadPopulation attributes and phenotypic data used to calculate stage-specific and cumulative inbreeding depression and drift load for 24 populations of Campanula americana. Column header descriptions are provided in the \u27column header descriptions\u27 tab.Koskietal_EvoLett_PhenotypicData_DriftLoad_InbreedingDepression.xlsxipyrad paramsParameter file associated with our processing of RADseq data in ipyradbellmergeAfter processing reads in ipyrad, the resulting data are stored in the variant call format (VCF) in bellmerge.vcf. These data can be analyzed with 3 R scripts to generate results presented in the paper.diversity R scriptExtracts estimates of the population mutation parameter and Tajima\u27s Ddiversity.Rinbreeding coefficient R scriptCalculates observed and expected heterozygosity from genotypic data and the inbreeding coefficient of populations.inbreeding coefficient.RTDoA R scriptCalculates directionality statistics and identifies the geographic location of a recent range expansion. To properly run this file, one must set a filepath containing the files in the TDoA dependencies folder.TDoA.RREADM