Evolution of individual variation in a competitive trait: a theoretical analysis.

When competitive traits are costly, negative frequency dependence can maintain genetic variance. Most theoretical studies examining this problem assume binary polymorphisms, yet most trait variation in wild populations is continuous. We propose that continuous trait variation can result from continuous variation in resource quality and that, specifically, the shape of the resource distribution determines trait maintenance.

Striatum supports fast learning but not memory recall.

Animals learn to carry out motor actions in specific sensory contexts to achieve goals. The striatum has been implicated in producing sensory-motor associations, yet its contribution to memory formation or recall is not clear. To investigate the contribution of striatum to these processes, mice were taught to associate a cue, consisting of optogenetic activation of striatum-projecting neurons in visual cortex, with forelimb reaches to access food pellets.

Variation in claw morphology among the digits of Bent-toed geckos (Cyrtodactylus: Gekkota: Gekkonidae).

Background: Ecomorphological studies of lizards have increasingly employed comparison of claw morphology among species in relation to spatial niche use. Typically, such studies focus on digit IV of the autopodia, especially the pes. Uniformity of claw morphology among digits is more often implicitly assumed than tested.

Participatory ergonomics: What works for whom and why? A realist review.

Participatory workplace interventions to improve workforce musculoskeletal health are infrequently analysed regarding why they work, for whom or under what circumstances. This review sought to identify intervention strategies which achieved genuine worker participation. In total, 3388 articles on participatory ergonomic (PE) interventions were screened; 23 were suitable to analyse within a realist framework identifying contexts, mechanisms of change, and outcomes.

The impact of mortality underreporting on the association of ambient temperature and PM with mortality risk in time series study.

Properly analyzing and reporting data remains a challenging task in epidemiologic research, as underreporting of data is often overlooked. The evaluation on the effect of underreporting remains understudied. In this study, we examined the effect of different scenarios of mortality underreporting on the relationship between PM, temperature, and mortality.

On the use of antibiotics in plasticity research: Gastropod shells unveil a tale of caution.

Through phenotypic plasticity, individual genotypes can produce multiple phenotypes dependent on the environment. In the modern world, anthropogenic influences such as man-made pharmaceuticals are increasingly prevalent. They might alter observable patterns of plasticity and distort our conclusions regarding the adaptive potential of natural populations.

Brain State-Dependent Modulation of Thalamic Visual Processing by Cortico-Thalamic Feedback.

The behavioral state of a mammal impacts how the brain responds to visual stimuli as early as in the dorsolateral geniculate nucleus of the thalamus (dLGN), the primary relay of visual information to the cortex. A clear example of this is the markedly stronger response of dLGN neurons to higher temporal frequencies of the visual stimulus in alert as compared with quiescent animals. The dLGN receives strong feedback from the visual cortex, yet whether this feedback contributes to these state-dependent responses to visual stimuli is poorly understood.

Managing an ageing healthcare workforce: a systematic literature review.

Purpose: The aim of this paper is to review research conducted on managing the ageing healthcare workforce and identify gaps for further research.

Design/methodology/approach: A systematic literature search of studies in the English language was carried out in Scopus and Web of Science databases.

Findings: The study consists of an analysis of 75 published articles.

Sperm competition in yellow dung flies: No consistent effect of sperm size.

The male competition for fertilization that results from female multiple mating promotes the evolution of increased sperm numbers and can impact sperm morphology, with theory predicting that longer sperm can at times be advantageous during sperm competition. If so, males with longer sperm should sire more offspring than competitors with shorter sperm. Few studies have directly tested this prediction, and findings are inconsistent.

Vegetation Height as the Primary Driver of Functional Changes in Orthopteran Assemblages in a Roadside Habitat.

Exhibiting manifold ecological impacts on terrestrial biota, roads have become a major driver of environmental change nowadays. However, many insect groups with high indication potential, such as grasshoppers and crickets (Orthoptera), have been largely neglected in road ecology research from a functional perspective. Using two complementary sampling methods, we have investigated the spatial dynamics of functional diversity and six functional traits in orthopteran assemblages, with respect to motorway proximity and the associated environmental factors, in a grassland habitat in the Lika region, Croatia.

Synthesis, Reactivity and Antimicrobial Activity of a Series of 2-Arylamino-1,3-selenazoles.

A series of 2-arylamino-1,3-selenazoles was synthesized and their reactivity was studied. The 2-arylamino-1,3-selenazoles and their reaction products were characterized by various spectroscopic methods and X-ray diffraction. In addition, the antimicrobial activity of the 2-arylamino-1,3-selenazoles in a panel of seven bacteria and fungi was examined.

Modelling migration in birds: competition's role in maintaining individual variation.

Animals exhibit extensive intraspecific variation in behaviour. Causes of such variation are less well understood. Here, we ask when competition leads to the maintenance of multiple behavioural strategies.

Male size and reproductive performance in three species of livebearing fishes (Gambusia spp.): A systematic review and meta-analysis.

The genus Gambusia represents approximately 45 species of polyandrous livebearing fishes with reversed sexual size dimorphism (i.e. males smaller than females) and with copulation predominantly via male coercion.

Material heterogeneity of male genitalia reduces genital damage in a bushcricket during sperm removal behaviour.

Sperm removal behaviour (SRB) is known in many animals, and male genital structures are often involved in the SRB, e.g. rubbing female genitalia vigorously.

Poor nutritional condition promotes high-risk behaviours: a systematic review and meta-analysis.

Animal behaviour can lead to varying levels of risk, and an individual's physical condition can alter the potential costs and benefits of undertaking risky behaviours. How risk-taking behaviour depends on condition is subject to contrasting hypotheses. The asset protection principle proposes that individuals in better condition should be more risk averse, as they have higher future reproductive potential (i.

The jury is still out regarding the generality of adaptive 'transgenerational' effects.

A recent meta-analysis concluded, 'transgenerational effects are widespread, strong and persistent'. We identify biases in the literature search, data and analyses, questioning that conclusion. Re-analyses indicate few studies actually tested transgenerational effects - making it challenging to disentangle condition-transfer from anticipatory parental effects, and providing little insight into the underlying mechanisms.

Impact of low sperm competition on male reproductive trait allometries in a bush-cricket.

Background: Studying reproductive trait allometries can help to understand optimal male investment strategies under sexual selection. In promiscuous mating systems, studies across several taxa suggest that testes allometry is usually positive, presumably due to strong selection on sperm numbers through intense sperm competition. Here, we investigated testes allometry in a bush-cricket species, Metaplastes ornatus, in which females mate promiscuously, but where sperm removal behaviour by males likely drastically reduces realised sperm competition level.

Cytoreductive Surgery (CRS) and Hyperthermic Intraperitoneal Chemotherapy (HIPEC): a Single-Center Experience in Austria.

Background: Cytoreductive surgery (CRS) and hyperthermic intraperitoneal chemotherapy (HIPEC) can significantly influence overall and disease-free survival in selected patients suffering from peritoneal surface malignancies (PSM) of various tumor entities. Because of the extent of the therapeutic approach, the associated morbidity and mortality and the multidisciplinarity needed, implementation of a CRS + HIPEC program at an institution is often challenging.

Methods: This single-center analysis included all patients (n = 60, 34 female, 26 male) with PSM from various tumor primaries [colorectal cancer (15/60; 25%), appendix neoplasia (21/60; 35%), and others (24/60; 40%)] treated with CRS + HIPEC at our institution between 2006 and 2014.

Sex-specific repeatabilities and effects of relatedness and mating status on copulation duration in an acridid grasshopper.

In species with direct sperm transfer, copulation duration is a crucial trait that may affect male and female reproductive success and that may vary with the quality of the mating partner. Furthermore, traits such as copulation duration represent the outcome of behavioral interactions between the sexes, for which it is important-but often difficult-to determine which sex is in phenotypic control. Using a double-mating protocol, we compared copulation durations between (1) virgin and nonvirgin and (2) sibling and nonsibling mating pairs in rufous grasshoppers .

Subcortical Source and Modulation of the Narrowband Gamma Oscillation in Mouse Visual Cortex.

Primary visual cortex exhibits two types of gamma rhythm: broadband activity in the 30-90 Hz range and a narrowband oscillation seen in mice at frequencies close to 60 Hz. We investigated the sources of the narrowband gamma oscillation, the factors modulating its strength, and its relationship to broadband gamma activity. Narrowband and broadband gamma power were uncorrelated.

Strong cryptic prezygotic isolation despite lack of behavioral isolation between sympatric host races of the leaf beetle Lochmaea capreae.

One of the major goals in speciation research is to understand which isolation mechanisms form the first barriers to gene flow. This requires examining lineages that are still in the process of divergence or incipient species. Here, we investigate the presence of behavioral and several cryptic barriers between the sympatric willow and birch host races of Lochmaea capreae.

A Paradox of Genetic Variance in Epigamic Traits: Beyond "Good Genes" View of Sexual Selection.

Maintenance of genetic variance in secondary sexual traits, including bizarre ornaments and elaborated courtship displays, is a central problem of sexual selection theory. Despite theoretical arguments predicting that strong sexual selection leads to a depletion of additive genetic variance, traits associated with mating success show relatively high heritability. Here we argue that because of trade-offs associated with the production of costly epigamic traits, sexual selection is likely to lead to an increase, rather than a depletion, of genetic variance in those traits.

Ecologically dependent and intrinsic genetic signatures of postzygotic isolation between sympatric host races of the leaf beetle Lochmaea capreae.

The fitness of hybrids might be compromised as a result of intrinsic isolation and/or because they fall between ecological niches due to their intermediate phenotypes ("extrinsic isolation"). Here, we present data from several crosses (parental crosses, F1, F2, and backcrosses) between the two host races of Lochmaea capreae on willow and birch to test for extrinsic isolation, intrinsic isolation, and environmentally dependent genetic incompatibilities. We employed a reciprocal transplant design in which offspring were raised on either host plant and their survival was recorded until adulthood.