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The article presents a study which aims to determine if encapsulation actually increased safety to poultry. The researchers used three encapsulated formulations that were fed to four groups of hens in dosages of actual Rabon blended with dry poultry mash. In addition, all samples used in the study were analyzed according to the modifications made by researcher known as Ivey. Based on the results, encapsulation increases the safety of an insecticide with regards to toxicity to the vertebrate host of the insect pest and safely controls dipterous insect pests in manure.

Premise: Reproductive fitness of individual plants depends on the timing of flowering, especially in mate‐limited populations, such as those in fragmented habitats. When flowering time traits are associated with differential reproductive success, the narrow‐sense heritability (h2) of traits will determine how rapidly trait means evolve in response to selection. Heritability of flowering time is documented in many annual plants. However, estimating h2 of flowering time in perennials presents additional methodological challenges, often including paternity assignment and trait expression over multiple years. Methods: We evaluated the h2 of onset and duration of flowering using offspring–midparent regressions and restricted maximum likelihood methods in an experimental population of an iterocarpic, perennial, herbaceous plant, Echinacea angustifolia, growing in natural conditions. We assessed the flowering time of the parental cohort in 2005 and 2006; the offspring in 2014 through 2017. We also examined the effects of the paternity assignment from Cervus and MasterBayes on estimates of h2. Results: We found substantial h2 for onset and duration of flowering. We also observed variation in estimates among years. The most reliable estimates for both traits fell in the range of 0.1–0.17. We found evidence of a genotype by year interaction for onset of flowering and strong evidence that genotypes are consistent in their duration of flowering across years. Conclusions: Substantial heritabilities in this population imply the capacity for a response to natural selection, while also suggesting the potential for differential contributions to adaptive evolution among seasons. [ABSTRACT FROM AUTHOR]

Disruption of gene flow among demes after landscape fragmentation can facilitate local adaptation but increase the effect of genetic drift and inbreeding. The joint effects of these conflicting forces on the mean fitness of individuals in a population are unknown. Through simulations, we explored the effect of increased isolation on the evolution of genetic load over the short and long term when fitness depends in part on local adaptation. We ignored genetic effects on demography. We modeled complex genomes, where a subset of the loci were under divergent selection in different localities. When a fraction of the loci were under heterogeneous selection, isolation increased mean fitness in larger demes made up of hundreds of individuals because of improved local adaptation. In smaller demes of tens of individuals, increased isolation improved local adaptation very little and reduced overall fitness. Short-term improvement of mean fitness after fragmentation may not be indicative of the long-term evolution of fitness. Whatever the deme size and potential for local adaptation, migration of one or two individuals per generation minimized the genetic load in general. The slow dynamics of mean fitness following fragmentation suggests that conservation measures should be implemented before the consequences of isolation on the genetic load become of concern. [ABSTRACT FROM AUTHOR]

Weedy species with wide geographical distributions may face strong selection to adapt to new environments, which can lead to adaptive genetic differentiation among populations. However, genetic drift, particularly due to founder effects, will also commonly result in differentiation in colonizing species. To test whether selection has contributed to trait divergence, we compared differentiation at eight microsatellite loci (measured as FST) to differentiation of quantitative floral and phenological traits (measured as QST) of wild radish (Raphanus raphanistrum) across populations from three continents. We sampled eight populations: seven naturalized populations and one from its native range. By comparing estimates of QST and FST, we found that petal size was the only floral trait that may have diverged more than expected due to drift alone, but inflorescence height, flowering time, and rosette formation have greatly diverged between the native and nonnative populations. Our results suggest the loss of a rosette and the evolution of early flowering time may have been the key adaptations enabling wild radish to become a major agricultural weed. Floral adaptation to different pollinators does not seem to have been as necessary for the success of wild radish in new environments. [ABSTRACT FROM AUTHOR]

Examines how genetic (co) variance matrices differ among populations in relation to the degree of genetic differentiation. Questions surrounding the differentiation of G matrices; Information on a study of the California wildflower, Clarkia dudleyana; Methodology of the study; Results of the study.

Despite the fundamental importance of mutation to the evolutionary process, we have little knowledge of the direct consequences of specific spontaneous mutations to the fitness of the organism. Combining results of whole-genome sequencing with repeated field assays of survival and reproduction, we quantify the combined effects on fitness of spontaneous mutations identified in Arabidopsis thaliana. We demonstrate that the effects are beneficial, deleterious, or neutral depending on the environmental context. Some lines, bearing mutations disrupting known loci, differ strongly in fitness from the founder or premutation genotype. Those effects vary across environments, for example, a line with a major deletion spanning a transcription factor gene expressed lower fitness than the founder under most conditions but exceeded the founder's fitness in one environment. The large contribution of genotype by environment interaction (G × E) to mutation effects on fitness implies spatial and/or temporal variation in selection on new mutations and could contribute to the maintenance of standing genetic variation. [ABSTRACT FROM AUTHOR]

Genetic correlations are the most commonly studied of all potential constraints on adaptive evolution. We present a comprehensive test of constraints caused by genetic correlation, comparing empirical results to predictions from theory. The additive genetic correlation between the filament and the corolla tube in wild radish flowers is very high in magnitude, is estimated with good precision (0.85 ± 0.06), and is caused by pleiotropy. Thus, evolutionary changes in the relative lengths of these two traits should be constrained. Still, artificial selection produced rapid evolution of these traits in opposite directions, so that in one replicate relative to controls, the difference between them increased by six standard deviations in only nine generations. This would result in a 54% increase in relative fitness on the basis of a previous estimate of natural selection in this population, and it would produce the phenotypes found in the most extreme species in the family Brassicaceae in less than 100 generations. These responses were within theoretical expectations and were much slower than if the genetic correlation was zero; thus, there was evidence for constraint. These results, coupled with comparable results from other species, show that evolution can be rapid despite the constraints caused by genetic correlations. [ABSTRACT FROM AUTHOR]

Background: Hurricanes Katrina and Rita struck the Gulf Coast forcing unprecedented mass evacuation and devastation. Texas 2-1-1 is a disaster communication hub between callers with unmet needs and community services at disaster sites and evacuation destinations. Purpose: To describe the location and timing of unmet disaster needs collected in real-time through Katrina–Rita disaster phases. Methods: In 2008–2010, a total of 25 data sets of Texas 2-1-1 calls from August–December 2005 were recoded and merged. In 2011–2012, analysis was performed of unmet need types, with comparisons over time and location; mapping was adjusted by population size. Results: Of 635,983 total 2-1-1 calls during the study period, 65% included primary disaster unmet needs: housing/shelter (28%); health/safety (18%); food/water (15%); transportation/fuel (4%). Caller demand spiked on Mondays, decreasing to a precipitous drop on weekends and holidays. Unmet needs surged during evacuation and immediate disaster response, remaining at higher threshold through recovery. Unmet need volume was concentrated in metropolitan areas. After adjusting for population size, “hot-spots” showed in smaller evacuation destinations and along evacuation routes. Conclusions: New disaster management strategies and policies are needed for evacuation destinations to support extended evacuation and temporary or permanent relocation. Planning and monitoring disaster resources for unmet needs over time and location could be targeted effectively using real-time 2-1-1 call patterns. Smaller evacuation communities were more vulnerable, exhausting their limited resources more quickly. Emergency managers should devise systems to more quickly authorize vouchers and reimbursements. As 2-1-1s expand and coordinate disaster roles nationwide, opportunities exist for analysis of unmet disaster needs to improve disaster management and enhance community resiliency. [ABSTRACT FROM AUTHOR]

In heterogeneous landscapes, the genetic and demographic consequences of dispersal influence the evolution of niche width. Unless pollen is limiting, pollen dispersal does not contribute directly to population growth. However, by disrupting local adaptation, it indirectly affects population dynamics. We compare the effect of pollen versus seed dispersal on the evolution of niche width in heterogeneous habitats, explicitly considering the feedback between maladaptation and demography. We consider two scenarios: the secondary contact of two subpopulations, in distinct, formerly isolated habitats, and the colonization of an empty habitat with dispersal between the new and ancestral habitat. With an analytical model, we identify critical levels of genetic variance leading to niche contraction (secondary contact scenario), or expansion (new habitat scenario). We confront these predictions with simulations where the genetic variance freely evolves. Niche contraction occurs when habitats are very different. It is faster as total gene flow increases or as pollen predominates in overall gene flow. Niche expansion occurs when habitat heterogeneity is not too high. Seed dispersal accelerates it, whereas pollen dispersal tends to retard it. In both scenarios very high seed dispersal leads to extinction. Overall, our results predict a wider niche for species dispersing seeds more than pollen., (© 2012 The Author(s). Evolution© 2012 The Society for the Study of Evolution.)

Mutations are the ultimate source of genetic diversity and their contributions to evolutionary process depend critically on their rate and their effects on traits, notably fitness. Mutation rate and mutation effect can be measured simultaneously through the use of mutation accumulation lines, and previous mutation accumulation studies measuring these parameters have been performed in laboratory conditions. However, estimation of mutation parameters for fitness in wild populations requires assays in environments where mutations are exposed to natural selection and natural environmental variation. Here we quantify mutation parameters in both the wild and greenhouse environments using 100 25th generation Arabidopsis thaliana mutation accumulation lines. We found significantly greater mutational variance and a higher mutation rate for fitness under field conditions relative to greenhouse conditions. However, our field estimates were low when scaled to natural environmental variation. Many of the mutation accumulation lines have increased fitness, counter to the expectation that nearly all mutations decrease fitness. A high mutation rate and a low mutational contribution to phenotypic variation may explain observed levels of natural genetic variation. Our findings indicate that mutation parameters are not fixed, but are variables whose values may reflect the specific environment in which mutations are tested.

Deleterious mutations are of fundamental importance to all aspects of organismal biology. Evolutionary geneticists have expended tremendous effort to estimate the genome-wide rate of mutation and the effects of new mutations on fitness, but the degree to which genomic mutational properties vary within and between taxa is largely unknown, particularly in multicellular organisms. Beginning with two highly inbred strains from each of three species in the nematode family Rhabditidae (Caenorhabditis briggsae, Caenorhabditis elegans, and Oscheius myriophila), we allowed mutations to accumulate in the relative absence of natural selection for 200 generations. We document significant variation in the rate of decay of fitness because of new mutations between strains and between species. Estimates of the per-generation mutational decay of fitness were very consistent within strains between assays 100 generations apart. Rate of mutational decay in fitness was positively associated with genomic mutation rate and negatively associated with average mutational effect. These results provide unambiguous experimental evidence for substantial variation in genome-wide properties of mutation both within and between species and reinforce conclusions from previous experiments that the cumulative effects on fitness of new mutations can differ markedly among related taxa.

Epistatic genetic variance for quantitative traits may play an important role in evolution, but detecting epistasis in diploid organisms is difficult and requires complex breeding programs and very large sample sizes. We develop a model for detecting epistasis in organisms with a free-living haploid stage in their life cycles. We show that epistasis is indicated by greater variance among families of haploid progeny derived from individual diploids than among clonally replicated haploid sibs from the same sporophyte. Simulations show that the power to detect epistasis is linearly related to the number of sporophytes and the number of haploids per sporophyte in the dataset. We illustrate the model with data from growth variation among gametophytes of the moss, Ceratodon purpureus. The experiment failed to detect epistatic variance for biomass production, although there was evidence of additive variance., (© 1997 The Society for the Study of Evolution.)