Evolution of female colours in birds: The role of female cost of reproduction and paternal care.

Female ornamentation is frequently observed in animal species and is sometimes found as more evolutionary labile than male ornamentation. A complex array of factors may explain its presence and variation. Here we assessed the role of female cost of reproduction and paternal care.

Long-Term Decrease in Coloration: A Consequence of Climate Change?

AbstractClimate change has been shown to affect fitness-related traits in a wide range of taxa; for instance, warming leads to phenological advancements in many plant and animal species. The influence of climate change on social and secondary sexual traits, which are associated with fitness because of their role as quality signals, is, however, unknown. Here, we use more than 5,800 observations collected on two Mediterranean blue tit subspecies ( and ) to explore whether blue crown and yellow breast patch colorations have changed over the past 15 years.

Are behaviour and stress-related phenotypes in urban birds adaptive?

Urbanisation is a world-wide phenomenon converting natural habitats into new artificial ones. Environmental conditions associated with urbanisation represent great challenges for wildlife. Behaviour and stress tolerance are considered of major importance in the adaptation to novel urban habitats and numerous studies already reported behavioural and stress response phenotypes associated with urbanisation, often suggesting they represented adaptations, while rarely demonstrating it.

Examining the link between relaxed predation and bird coloration on islands.

Insular ecosystems share analogous ecological conditions, leading to patterns of convergent evolution that are collectively termed as the 'island syndrome'. In birds, part of this syndrome is a tendency for a duller plumage, possibly as a result of relaxed sexual selection. Despite this global pattern, some insular species display a more colourful plumage than their mainland relatives, but why this occurs has remained unexplained.

oXiris® Use in Septic Shock: Experience of Two French Centres.

Background: Sepsis is a dysregulated host response to an infection and can result in organ dysfunctions and death. Extracorporeal blood purification techniques aim to improve the prognosis of these patients by modulating the unbalanced immune response. This study reports our experience with the use of the oXiris® membrane for septic shock patients requiring continuous renal replacement therapy (CRRT).

Urban versus forest ecotypes are not explained by divergent reproductive selection.

Increasing urbanization offers a unique opportunity to study adaptive responses to rapid environmental change. Numerous studies have demonstrated phenotypic divergence between urban and rural organisms. However, comparing the direction and magnitude of natural selection between these environments has rarely been attempted.

Great tits and the city: Distribution of genomic diversity and gene-environment associations along an urbanization gradient.

Urbanization is a growing concern challenging the evolutionary potential of wild populations by reducing genetic diversity and imposing new selection regimes affecting many key fitness traits. However, genomic footprints of urbanization have received little attention so far. Using RAD sequencing, we investigated the genomewide effects of urbanization on neutral and adaptive genomic diversity in 140 adult great tits collected in locations with contrasted urbanization levels (from a natural forest to highly urbanized areas of a city; Montpellier, France).

Nest design in a changing world: great tit nests from a Mediterranean city environment as a case study.

Investigations of urbanization effects on birds have focused mainly on breeding traits expressed after the nest-building stage (e.g. first-egg date, clutch size, breeding success, and offspring characteristics).

Disentangling drivers of reproductive performance in urban great tits: a food supplementation experiment.

Worldwide urban expansion induces degradation of the natural environment, resulting in new constraints in terms of breeding sites, anthropogenic disturbances as well as food resources. The alteration of resource abundance and type may induce non-adaptive investments in reproduction from urban dwellers. Food availability and quality have been identified as potential drivers of the decline in passerine body mass and fledging success in urbanized landscapes, particularly if birds misinterpret cues of food abundance used to adjust their reproductive investment.

Assortative mating by colored ornaments in blue tits: space and time matter.

Assortative mating is a potential outcome of sexual selection, and estimating its level is important to better understand local adaptation and underlying trait evolution. However, assortative mating studies frequently base their conclusions on small numbers of individuals sampled over short periods of time and limited spatial scales even though spatiotemporal variation is common. Here, we characterized assortative mating patterns over 10 years in four populations of the blue tit (), a passerine bird.

Peripheral venous catheter insertion simulation training: A randomized controlled trial comparing performance after instructor-led teaching versus peer-assisted learning.

Introduction: Peripheral venous catheter insertion is a procedural skill that every medical student should master. Training is often limited to a small number of students and is poorly evaluated. The objective of this study was to evaluate the performance of peer-assisted learning in comparison to instructor-led teaching for peripheral venous catheter insertion training.

Interspecific variation in the relationship between clutch size, laying date and intensity of urbanization in four species of hole-nesting birds.

The increase in size of human populations in urban and agricultural areas has resulted in considerable habitat conversion globally. Such anthropogenic areas have specific environmental characteristics, which influence the physiology, life history, and population dynamics of plants and animals. For example, the date of bud burst is advanced in urban compared to nearby natural areas.

Worldwide patterns of bird colouration on islands.

Island environments share distinctive characteristics that offer unique opportunities to investigate parallel evolution. Previous research has produced evidence of an island syndrome for morphological traits, life-history strategies and ecological niches, but little is known about the response to insularity of other important traits such as animal signals. Here, we tested whether birds' plumage colouration is part of the island syndrome.

The intensity threshold of colour vision in a passerine bird, the blue tit (Cyanistes caeruleus).

Many vertebrates use colour vision for vital behaviour but their visual performance in dim light is largely unknown. The light intensity threshold of colour vision is known only for humans, horses and two parrot species. Here, we first explore this threshold in a passerine bird, the blue tit (Cyanistes caeruleus).

Females tend to prefer genetically similar mates in an island population of house sparrows.

Background: It is often proposed that females should select genetically dissimilar mates to maximize offspring genetic diversity and avoid inbreeding. Several recent studies have provided mixed evidence, however, and in some instances females seem to prefer genetically similar males. A preference for genetically similar mates can be adaptive if outbreeding depression is more harmful than inbreeding depression or if females gain inclusive fitness benefits by mating with close kin.

Assessing multivariate constraints to evolution across ten long-term avian studies.

Background: In a rapidly changing world, it is of fundamental importance to understand processes constraining or facilitating adaptation through microevolution. As different traits of an organism covary, genetic correlations are expected to affect evolutionary trajectories. However, only limited empirical data are available.

Female blue tits with brighter yellow chests transfer more carotenoids to their eggs after an immune challenge.

Female ornaments are present in many species, and it is more and more accepted that sexual or social selection may lead to their evolution. By contrast, the information conveyed by female ornaments is less well understood. Here, we investigated the links between female ornaments and maternal effects.

Eggshell spottiness reflects maternally transferred antibodies in blue tits.

Blue-green and brown-spotted eggshells in birds have been proposed as sexual signals of female physiological condition and egg quality, reflecting maternal investment in the egg. Testing this hypothesis requires linking eggshell coloration to egg content, which is lacking for brown protoporphyrin-based pigmentation. As protoporphyrins can induce oxidative stress, and a large amount in eggshells should indicate either high female and egg quality if it reflects the female's high oxidative tolerance, or conversely poor quality if it reflects female physiological stress.

Testing hypotheses in evolutionary ecology with imperfect detection: capture-recapture structural equation modeling.

Studying evolutionary mechanisms in natural populations often requires testing multifactorial scenarios of causality involving direct and indirect relationships among individual and environmental variables. It is also essential to account for the imperfect detection of individuals to provide unbiased demographic parameter estimates. To cope with these issues, we developed a new approach combining structural equation models with capture-recapture models (CR-SEM) that allows the investigation of competing hypotheses about individual and environmental variability observed in demographic parameters.

Female plumage coloration is sensitive to the cost of reproduction. An experiment in blue tits.

1. A growing number of studies suggest that female ornaments are linked to maternal quality and influence male mate choice. These findings challenge the traditional male-biased view of sexual selection and the hypothesis that female ornaments are the outcome of a genetic correlation with male ornaments.