Gastrointestinal bacteria play a central role in the health of animals. The that individuals acquire as they age may therefore have profound consequences for their future fitness. However, changes microbial community structure with host remain poorly understood. We characterised cloacal assemblages chicks and adults natural population black-legged kittiwakes (Rissa tridactyla), using molecular methods. show kittiwake cloaca hosts diverse assemblage bacteria. A greater number total bacterial...

Despite the increasing knowledge on processes involved in acquisition and development of gut microbiota model organisms, factors influencing early successions natural populations remain poorly understood. In particular, little is known role rearing environment establishment wild birds. Here, we examined influence nesting Great tits (Parus major) by performing a partial cross-fostering experiment during intermediate stage nestling development. We found that cloacal great tit nestlings...

Urban sprawl increasingly affects the ecology of natural populations, including host-microbiota interactions, with observed differences in gut microbiota between urban and rural hosts. While different mechanisms could explain this pattern, dietary uptake constitutes a likely candidate. To assess contribution diet explaining urban-rural variation microbiota, we performed an aviary experiment which house sparrows were fed mimics or diets. Before experiment, hosted more diverse communities,...

-Blood was analyzed from 151 pelagic marine birds to establish reference ranges for hematological and plasma biochemical parameters healthy, wild populations of Pacific seabirds. Of the 13 species examined, 9 were Family Alcidae (N = 122 individuals) remainder 29) Families Phalacrocoracidae, Laridae, Procellariidae. Three 8 (total white blood cell count, lymphocyte count eosinophil count) differed significantly among species, as did (alkaline phosphatase, aspartate aminotransferase, creatine...

Public information (PI), which is the that can be derived from behavior and performance of conspecifics, has been demonstrated to used in many fitness-enhancing decisions. In context breeding habitat choice, PI use called "habitat copying." We experimentally tested existence copying Blue Tit (Cyanistes caeruleus), a nonmigratory, short-lived hole-nesting bird. manipulated mean number fledglings raised locally (quantity) their condition (quality) as components by transferring nestlings...

Sexually transmitted diseases have often been suggested as a potential cost of multiple mating and playing major role in the evolution systems. Yet there is little empirical data relating strategies to sexually microorganisms wild populations. We investigated whether behaviour influences diversity composition cloacal assemblages by comparing bacterial communities cloaca monandrous polyandrous female common lizards Zootoca vivipara sampled after period. found that females harboured more...

The microbiota is suggested to be a fundamental contributor host reproduction and survival, but associations between fitness are rare, especially for wild animals. Here, we tested the association two proxies of breeding performance in multiple body sites black-legged kittiwake, seabird species. First found that, females, nonbreeders (i.e., birds that did not lay eggs) hosted different composition breeders neck flank feathers, choanae, outer-bill cloacae, preen feathers tracheae. These...

Sex allocation theory proposes that parents should bias the sex ratio of their offspring if reproductive value one is greater than other. In monogamous blue tit (Parus caeruleus), males have a variance in success females, and high-quality higher females due to extrapair paternity. Consequently, mating with attractive are expected produce broods biased toward sons, as sons benefit more daughters from inheriting father's characteristics. Song plumage color birds secondary sexual characters...

Sperm aging is known to be detrimental reproductive performance. However, this apparently general phenomenon has seldom been studied in an evolutionary context. The negative impact of sperm on parental fitness should constitute a strong selective pressure for adaptations avoid its effects. We the black-legged kittiwakes ( Rissa tridactyla ), monogamous seabird. Kittiwakes comprise model system because i ) evidence that females eject their mates' prevent fertilization by would old and...

Sex allocation theory predicts that parents should favor offspring of the sex provides greatest fitness return.Despite growing evidence suggesting vertebrates are able to overcome constraint chromosomal determination, general pattern remains equivocal, indicating a need for experimental investigations.We used an feeding design study during 3 years in black-legged kittiwakes (Rissa tridactyla).Intense male-male competition securing breeding site is common this species which males heavier and...

Evidence of multiple genetic criteria mate choice is accumulating in numerous taxa. In many species, females have been shown to pair with genetically dissimilar mates or extra-pair partners that are more compatible than their social mates, thereby increasing offsprings' heterozygosity which often correlates offspring fitness. While most studies focused on promiscuous few addressed monogamous tends be mutual. Here, we used microsatellite markers assess individual global and similarity pairs a...

Wild organisms face environmental stressors that can interact and affect their health unexpectedly. Evidence suggests responses to may be mediated by changes in the gut microbiota, with cascading effects on host health. However, combined of multiple microbiota are still overlooked. Here, we investigated single interactive realistic metal contamination (i.e., a mixture Cd, Cu, Zn) an immune challenge lipopolysaccharides - LPS phytohaemagglutinin PHA) mimicking parasite attack taxonomic...

The gut microbiota is crucial for host health and can be impacted by various environmental disruptions, yet the effects of multiple pesticide exposures on farmland organisms' microbiomes remain largely unexplored. We assessed changes in a wild apex predator exposed to pesticides agricultural landscapes. Pesticides, including acetochlor quinoxyfen, which are supposed banned, were significantly positively correlated with certain key bacteria from Actinobacteria, Alphaproteobacteria...

Urbanization constitutes one of the most profound forms land-use change and strongly affects global biodiversity ecosystem functioning. Expansion urban areas typically leads to species loss but may also induce more subtle changes in dynamics through selection or plasticity. Using a dual correlative (field) experimental (aviary) approach, we here show that free-ranging house sparrows southern France were smaller lighter than their rural counterparts after allometric scaling, whereas 2...

Species interactions are central in predicting the impairment of biodiversity with climate change. Trophic may be altered through climate-dependent changes either predator food preferences or prey communities. Yet, change impacts on diet remain surprisingly poorly understood. We experimentally studied consequences 2°C warmer climatic conditions trophic niche a generalist lizard predator. used system semi-natural mesocosms housing variety invertebrate species and which were manipulated....

SUMMARY In non-permanent parasites with low intrinsic mobility such as ticks, dispersal is highly dependent on host movements well the timing of separation from hosts. Optimal detachment behaviour all more crucial in nidicolous ticks risk detaching non-suitable habitat high. this study, we experimentally investigated Ixodes arboricola , a tick that primarily infests birds roosting tree-holes. We infested great tits I. larvae or nymphs, and submitted to 2 experimental treatments, control...

Recent studies in humans have shown that certain pesticides could affect the composition and functions of gut microbiota, an essential modulator vertebrate physiology, leading to potential dysbiosis. However, this relationship remains largely unknown wild birds despite implications current decline farmland species. The present study sought fill gap by providing data on association between pesticide concentrations blood microbiota characteristics relation individual traits a raptor, Montagu's...