| discrepancies in population differentiation at microsatellites, mitochondrial dna and plumage colour in the pied flycatcher--inferring evolutionary processes. | genetic differentiation between three populations of the pied flycatcher ficedula hypoleuca (norway, czech republic and spain, respectively) was investigated at microsatellite loci and mitochondrial dna (mtdna) sequences and compared with the pattern of differentiation of male plumage colour. the czech population lives sympatrically with the closely related collared flycatcher (f. albicollis) whereas the other two are allopatric. allopatric populations are on average more conspicuously coloured ... | 2000 | 10964233 |
| single-nucleotide polymorphism characterization in species with limited available sequence information: high nucleotide diversity revealed in the avian genome. | as a case study for single-nucleotide polymorphism (snp) identification in species for which little or no sequence information is available, we investigated several approaches to identifying snps in two passerine bird species: pied and collared flycatchers (ficedula hypoleuca and f. albicollis). all approaches were successful in identifying sequence polymorphism and over 50 candidate snps per species were identified from approximately 9.1 kb of sequence. in addition, 17 sites were identified in ... | 2002 | 11918793 |
| contrasting patterns of polymorphism and divergence on the z chromosome and autosomes in two ficedula flycatcher species. | in geographic areas where pied and collared flycatchers (ficedula hypoleuca and f. albicollis) breed in sympatry, hybridization occurs, leading to gene flow (introgression) between the two recently diverged species. notably, while such introgression is observable at autosomal loci it is apparently absent at the z chromosome, suggesting an important role for genes on the z chromosome in creating reproductive isolation during speciation. to further understand the role of z-linked loci in the forma ... | 2005 | 15956661 |
| pollution-related changes in diets of two insectivorous passerines. | insectivorous birds living in polluted areas are not only exposed to pollutants but they may also be affected by changes in their invertebrate food. the populations of many invertebrate species are affected by environmental pollution and such changes may lead to differences in the diet of insectivorous birds. we examined nestling food quality (invertebrate composition and heavy metal levels) and breeding performance of two cavity-nesting passerines, the great tit, parus major, and the pied flyca ... | 2005 | 16044352 |
| species divergence in offspring begging intensity: difference in need or manipulation of parents? | conflicts over the delivery and sharing of food among family members are expected to lead to evolution of exaggerated offspring begging for food. coevolution between offspring begging intensity and parent response depends on the genetic architecture of the traits involved. given a genetic correlation between offspring begging intensity and parental response, there may be fast and arbitrary divergence in these behaviours between populations. however, there is limited knowledge about the genetic b ... | 2007 | 17264061 |
| prehatching maternal investment and offspring immunity in the pied flycatcher (ficedula hypoleuca). | maternal investment in offspring immunity via egg quality may be an adaptive evolutionary strategy shaped by natural selection. we investigated how maternal investment in eggs can influence offspring immunity by conducting two experiments. first, we manipulated foraging performance of the mothers before egg laying by attaching a small weight to their back feathers. during the nestling period, we investigated offspring total antibody production at the age of 7 days and after antibody challenge, a ... | 2007 | 17305837 |
| characterization of the first growth hormone gene sequence for a passerine bird--the pied flycatcher (ficedula hypoleuca). | while the growth hormone (gh) gene has been characterized in a broad range of vertebrates, surprisingly little is known about this gene in birds. in order to extend knowledge of the gh gene in avian species and non-domestic species, the pied flycatcher (ficedula hypoleuca) gh gene has been sequenced in this study. the overall average pairwise sequence divergence level was 0.08 among all available avian sequences and 0.27 among other taxa. however, the overall genetic organization of the gene is ... | 2006 | 17381040 |
| oxidative stress in pied flycatcher (ficedula hypoleuca) nestlings from metal contaminated environments in northern sweden. | metals have been shown to induce oxidative stress in animals. one of the most metal polluted terrestrial environments in sweden is the surroundings of a sulfide ore smelter plant located in the northern part of the country. pied flycatcher nestlings (ficedula hypoleuca) that grew up close to the industry had accumulated amounts of arsenic, cadmium, mercury, lead, iron and zinc in their liver tissue. the aim of this study was to investigate if pied flycatcher nestlings in the pollution gradient o ... | 2007 | 17631289 |
| effects of reduced lead deposition on pied flycatcher (ficedula hypoleuca) nestlings: tracing exposure routes using stable lead isotopes. | to what extent the lead burden of birds living in strongly contaminated ecosystems is responding to decreased atmospheric lead deposition is not well known. in this study, we measured lead concentrations and stable lead isotope ratios (206pb/207pb and 208pb/207pb) in liver and feces from pied flycatcher nestlings (ficedula hypoleuca) along a 90 km pollution gradient from the rönnskär smelter in northern sweden. changes in lead concentration in the birds from 1984 to 2006 were used for assessing ... | 2009 | 19209608 |
| isospora hypoleucae sp. n. (apicomplexa: eimeriidae), a new coccidian parasite found in the pied flycatcher (ficedula hypoleuca). | a new coccidia species is reported from the natural population of pied flycatcher (ficedula hypoleuca) in northern germany. sporulated oocysts were found in faeces from 6 of 8 sampled adults. the spherical oocysts of the new isospora species have a brownish, smooth, bi-layered wall. average size of sporulated oocysts was 19.4 x 19.3 microm (17.5-22.8 microm x 17.5-22.8 microm ) with a shape index (length/width) of 1.0. the sporulated oocysts have no micropyle or residuum, but enclose several sma ... | 2009 | 19450377 |
| lead exposure and biological effects in pied flycatchers (ficedula hypoleuca) before and after the closure of a lead mine in northern sweden. | mining activities affect the surrounding environment by increasing exposure to metals. in this study, metal accumulation and its effects on reproduction and health of pied flycatcher (ficedula hypoleuca) nestlings were monitored before and up to five years after a lead mine and enrichment plant closed down. the lead concentration in moss, nestling blood, liver and feces all indicated decreased lead exposure by at least 31% after closure, although only blood lead decreased significantly. although ... | 2010 | 20116150 |
| effects of pollution on land snail abundance, size and diversity as resources for pied flycatcher, ficedula hypoleuca. | passerine birds need extra calcium during their breeding for developing egg shells and proper growth of nestling skeleton. land snails are an important calcium source for many passerines and human-induced changes in snail populations may pose a severe problem for breeding birds. we studied from the bird's viewpoint how air pollution affects the shell mass, abundance and diversity of land snail communities along a pollution gradient of a copper smelter. we sampled remnant snail shells from the ne ... | 2010 | 20542535 |
| predator proximity as a stressor in breeding flycatchers: mass loss, stress protein induction, and elevated provisioning. | we investigated the physiological and behavioral consequences for prey breeding at different distances from a nesting predator. in a natural setting, pied flycatchers (ficedula hypoleuca) made territory location decisions relative to established sparrowhawk (accipiter nisus) nests. from female flycatchers attending nests at different distances from sparrowhawk nests, we measured body mass, blood stress protein (hsp60 and hsp70), and plasma immunoglobulin levels at the beginning (initial) and end ... | 2010 | 20583723 |
| permanent genetic resources added to molecular ecology resources database 1 january 2009-30 april 2009. | this article documents the addition of 283 microsatellite marker loci to the molecular ecology resources database. loci were developed for the following species: agalinis acuta; ambrosia artemisiifolia; berula erecta; casuarius casuarius; cercospora zeae-maydis; chorthippus parallelus; conyza canadensis; cotesia sesamiae; epinephelus acanthistius; ficedula hypoleuca; grindelia hirsutula; guadua angustifolia; leucadendron rubrum; maritrema novaezealandensis; meretrix meretrix; nilaparvata lugens; ... | 2009 | 21564911 |
| behavioral, hormonal, and morphological responses of free-living male pied flycatchers to estradiol treatment of their mates. | a field experiment was performed implanting female pied flycatchers (ficedula hypoleuca) during the nest-building period with silastic tubes containing 17 beta-estradiol. control females were given empty silastic tubes. the pied flycatcher is a polygamous and polyterritorial bird species. during two successive breeding seasons effects on reproductive behavior and the reproductive systems of males were studied. reproductive success was not affected by the treatment. estradiol treatment of females ... | 2007 | 2045090 |
| photoperiod as a modifying and limiting factor in the expression of avian circannual rhythms. | in three species of birds that migrate long distances, the annual rhythms of gonadal activity, molt, and migratory restlessness (zugunruhe) persist for more than 1 year under certain constant conditions. the most important zeitgeber for these circannual rhythms is the annual cycle of photoperiod, which adjusts the overall period of circannual rhythms to exactly 1 year and also provides for the appropriate adjustment of seasonal activities to the temporal structure of the environment. this is ill ... | 2008 | 2519591 |
| egg colour reflects the amount of yolk maternal antibodies and fledging success in a songbird. | blue-green colours in avian eggs have been proposed as post-mating signals of female phenotypic quality to their mates. egg colour may not only indicate female value, but also the quality of the eggs themselves and of resulting offspring. to date, there has been no demonstration of an association between egg colour and egg or offspring immune quality. we here show that the intensity of blue-green colour of pied flycatcher ficedula hypoleuca eggs reflects the amount of maternal antibodies in the ... | 2006 | 17148396 |
| large brood sizes of pied flycatcher, sparrowhawk and goshawk in peak microtine years: support for the mast depression hypothesis. | the mast depression hypothesis (mdh) proposes that cyclic population fluctuations of microtines and other herbivores are an effect of cyclic seed cropping of plants. this is because high seed crops, termed masts, are produced at the expense of chemical defence against herbivores. it has generally been assumed that bird-hunting raptors produce high numbers of offspring when microtine prey are abundant because of reduced competition from generalist predators. however, this may also be caused by hi ... | 1998 | 28307513 |
| habitat selection as an antipredator behaviour in a multi-predator landscape: all enemies are not equal. | 1. breeding territory choice constitutes a crucial antipredator behaviour for animals that determines reproductive success and survival during the breeding season. on arrival to breeding grounds migrant prey face a multitude of 'waiting' predators already settled within the landscape. 2. we studied territory selection and reproductive investment of migrant pied flycatcher (ficedula hypoleuca) relative to breeding pygmy owls (pos) (glaucidium passerinum) and tengmalm's owls (tos) (aegolius funere ... | 2010 | 19912426 |
| isospora serinuse n. sp. (apicomplexa: eimeriidae) from a domestic canary (serinus canaria forma domestica) (passeriformes: fringillidae) in western australia. | a new species, isospora serinuse n. sp., (apicomplexa:eimeriidae) is described from a single domestic canary (serinus canaria forma domestica) (subspecies s. c. domestica) in western australia. sporulated oocysts of isospora serinuse n. sp. are spherical or subspherical, 25.5 (24.4-27.0) × 23.5 (22.0-24.8) μm, with a shape index (length/width) of 1.09; and a smooth bilayered oocyst wall, 1.2 μm thick (outer layer 0.9 μm, inner 0.3 μm). a polar granule is present, but a micropyle and oocyst resid ... | 2015 | 26325434 |
| polymorphism at the clock gene predicts phenology of long-distance migration in birds. | dissecting phenotypic variance in life history traits into its genetic and environmental components is at the focus of evolutionary studies and of pivotal importance to identify the mechanisms and predict the consequences of human-driven environmental change. the timing of recurrent life history events (phenology) is under strong selection, but the study of the genes that control potential environmental canalization in phenological traits is at its infancy. candidate genes for circadian behaviou ... | 2015 | 25780812 |
| active hiding of social information from information-parasites. | coevolution between pairs of different kind of entities, such as providers and users of information, involves reciprocal selection pressures between them as a consequence of their ecological interaction. pied flycatchers (ficedula hypoleuca) have been shown to derive fitness benefits (larger clutches) when nesting in proximity to great tits (parus major), presumably because they this way discover and obtain information about nesting sites. tits suffer from the resulting association (smaller clut ... | 2014 | 24580842 |
| distribution of aromatase activity in the brain and peripheral tissues of passerine and nonpasserine avian species. | many behavioral effects of testosterone on hypothalamic and limbic brain areas are mediated by the action, at the cellular level, of estrogens derived from local testosterone aromatization. aromatase activity and cells containing the aromatase protein and mrna have accordingly been identified in the brain areas involved in the control of behavior. the presence of an unusually high level of aromatase activity has been detected in the telencephalon of one songbird species, the zebra finch (taeniop ... | 2000 | 10620422 |
| 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. in some birds, breeding success is determined by synchrony between timing of breeding and peak food abundance. pert ... | 2016 | 27547364 |
| host specificity of a bird-specialised endophilic ectoparasite, the tree-hole tick ixodes arboricola. | host specialisation in parasites can be due to either limited exposure or limited adaptation to different host types. when the first barrier is lifted experimentally, the degree of adaptive specialisation can be studied. the tree-hole tick ixodes arboricola is an endophilic parasite with a narrow host range, found in nest boxes used mainly by great and blue tits (parus major, cyanistes caeruleus) and to a lesser extent by pied flycatchers (ficedula hypoleuca) and nuthatches (sitta europaea). in ... | 2014 | 25231076 |
| oxidative status in nestlings of three small passerine species exposed to metal pollution. | antioxidant defense has an important role in the protection of organisms against oxidative stress caused by reactive oxygen species (ros). many metals are capable of generating ros and inducing oxidative damage, and may therefore lead to changes in oxidative regulation. we studied species-specific variation in the oxidative status of great tit (parus major), blue tit (cyanistes caeruleus) and pied flycatcher (ficedula hypoleuca) nestlings in a vicinity of a non-ferrous smelter. non-enzymatic (gl ... | 2013 | 23567166 |
| plasma carotenoid levels are not directly related to heavy metal exposure or reproductive success in three insectivorous passerines. | the authors measured plasma carotenoid levels in three insectivorous bird species, the pied flycatcher (ficedula hypoleuca), the blue tit (cyanistes caeruleus), and the great tit (parus major) in metal-polluted and unpolluted sites around a copper smelter. their aim was to determine whether there was interspecific, age-related, or yearly variation in carotenoid levels and their responses to the ambient pollution level. the three bird species showed qualitatively and quantitatively similar carote ... | 2012 | 22488531 |
| what prevents phenological adjustment to climate change in migrant bird species? evidence against the "arrival constraint" hypothesis. | phenological studies have demonstrated changes in the timing of seasonal events across multiple taxonomic groups as the climate warms. some northern european migrant bird populations, however, show little or no significant change in breeding phenology, resulting in synchrony with key food sources becoming mismatched. this phenological inertia has often been ascribed to migration constraints (i.e. arrival date at breeding grounds preventing earlier laying). this has been based primarily on resear ... | 2011 | 20405299 |
| corticosterone metabolites in blue tit and pied flycatcher droppings: effects of brood size, ectoparasites and temperature. | the hypothalamic-pituitary-adrenal (hpa) axis of birds induces the secretion of corticosterone (cort) as a response to different ecological variables. in this study we tested experimentally if manipulations of brood size or ectoparasitism led to subsequent differences in the concentration of excreted cort metabolites of adult and nestling blue tits (cyanistes caeruleus). no significant effect of the manipulation of brood size was detected in adults or nestlings. no significant effect of ectopara ... | 2008 | 18062967 |
| mate choice and imprinting in birds studied by cross-fostering in the wild. | sexual-selection theories generally assume that mating preferences are heritable traits. however, there is substantial evidence that the rearing environment may be important for the development of mating preferences, indicating that they may be learnt, or modified by experience. the relative importance of such sexual imprinting across species remains largely unexplored. here, we report results of a large-scale cross-fostering experiment in the wild in which nestling birds were raised by parents ... | 2002 | 12137574 |
| developmental changes in 7-ethoxyresorufin-o-deethylase (erod) and delta-aminolevulinic acid dehydratase (ala-d) activities in three passerines. | in this study, we report changes in 7-ethoxyresorufin-o-deethylase (erod) and delta-aminolevulinic acid dehydratase (ala-d) enzyme activities during development of three wild passerine bird species: pied flycather (ficedula hypoleuca), great tit (parus major) and blue tit (p. caeruleus). activities were determined from late embryos, newly hatched, 1-week-old and 15-day-old nestlings and adult birds. erod activity from hepatic microsomes and ala-d activity from liver tissue and erythrocytes were ... | 1999 | 10622436 |
| a mathematical expectation model for bird navigation based on the clock-and-compass strategy. | we present here a mathematical formula for the directional distribution of migratory birds if they use a vector navigation/clock-and-compass strategy to find their winter quarters. it is based on mathematical expectation theory and shows that a simple parabola can describe the expected geographical spread of clock-and-compass birds as a function of migratory distance. predictions based on this model are then tested against all same autumn ringing recoveries of first-season pied flycatchers, fice ... | 2000 | 11034834 |
| neighborhood effects in bird distributions, navarre, spain | this study examines the role of neighborhood effects in the spatial distributions of selected bird species in navarre, spain. we employed a geographic information system (gis) to organize the data on bird distributions and relevant environmental variables and to analyze their spatial patterns. three bird species were selected for analysis: the european honey-buzzard (pernis apivorus), the eurasian hobby (falco subbuteo), and the european pied flycatcher (ficedula hypoleuca). selected environment ... | 1996 | 8703105 |
| climate adaptation and speciation: particular focus on reproductive barriers in ficedula flycatchers. | climate adaptation is surprisingly rarely reported as a cause for the build-up of reproductive isolation between diverging populations. in this review, we summarize evidence for effects of climate adaptation on pre- and postzygotic isolation between emerging species with a particular focus on pied (ficedula hypoleuca) and collared (ficedula albicollis) flycatchers as a model for research on speciation. effects of climate adaptation on prezygotic isolation or extrinsic selection against hybrids h ... | 2016 | 27087843 |
| hormonally-mediated maternal effects in birds: lessons from the flycatcher model system. | maternal effects are a crucial mechanism in many taxa in generating phenotypic variation, affecting offspring development and fitness and thereby potentially adapting them to their expected environments. androgen hormones in bird eggs have attracted considerable interest in past years, and it is frequently assumed that their concentrations in eggs are shaped by darwinian selection. currently, however, the data is scattered over species with very different life-history strategies, environments an ... | 2015 | 26393309 |
| sympatric divergence and clinal variation in multiple coloration traits of ficedula flycatchers. | geographic variation in phenotypes plays a key role in fundamental evolutionary processes such as local adaptation, population differentiation and speciation, but the selective forces behind it are rarely known. we found support for the hypothesis that geographic variation in plumage traits of the pied flycatcher ficedula hypoleuca is explained by character displacement with the collared flycatcher ficedula albicollis in the contact zone. the plumage traits of the pied flycatcher differed strong ... | 2015 | 25683091 |
| optimizing the trade-off between offspring number and quality in unpredictable environments: testing the role of differential androgen transfer to collared flycatcher eggs. | according to the brood reduction hypothesis, parents adjust their brood size in response to current environmental conditions. when resources are abundant, parents can successfully raise all hatched offspring, but when resources are scarce, brood reduction, i.e., the sacrifice of some siblings to secure the quality of a subset of offspring, may maximize fitness. differential transfer of maternal androgens is one potential proximate mechanism through which female birds may facilitate brood reducti ... | 2013 | 23602767 |
| speciation in ficedula flycatchers. | speciation in animals often requires that population divergence goes through three major evolutionary stages, i.e. ecological divergence, development of sexual isolation and the build-up of genetic incompatibility. there is theoretical consensus regarding favourable conditions required for speciation to reach its final and irreversible stage, but empirical tests remain rare. here, we review recent research on processes of speciation, based on studies in hybrid zones between collared (ficedula al ... | 2010 | 20439285 |
| ecology and genetics of speciation in ficedula flycatchers. | birds have for long been popular study objects in speciation research. being easy to observe in the field, they have traditionally been particularly important in studies of behavioural and ecological factors in speciation, whereas the genetic aspects of the process have been studied in other organisms, such as drosophila. more recently, however, a stronger genetic focus has been placed on speciation research also in birds. here, we review ecological, behavioural and genetic studies on speciation ... | 2010 | 20163542 |
| seventy new microsatellites for the pied flycatcher, ficedula hypoleuca and amplification in other passerine birds. | the pied flycatcher (ficedula hypoleuca) is a small migratory passerine bird commonly distributed across europe which has been the focus of considerable ecological and evolutionary research. here, we present details of 70 microsatellite markers for the species adding to the six which are currently available. sixty-six markers were also polymorphic in the closely related collared flycatcher (ficedula albicollis), while 54 were polymorphic in another related passerine, the bluethroat (luscinia sve ... | 2008 | 21585917 |
| natural and sexual selection against hybrid flycatchers. | while sexual selection is generally assumed to quickly cause or strengthen prezygotic barriers between sister species, its role in causing postzygotic isolation, through the unattractiveness of intermediate hybrids, is less often examined. combining 24 years of pedigree data and recently developed species-specific molecular markers from collared (ficedula albicollis) and pied (ficedula hypoleuca) flycatchers and their hybrids, we were able to quantify all key components of fitness. to disentangl ... | 2008 | 18211878 |
| does migration of hybrids contribute to post-zygotic isolation in flycatchers? | in the face of hybridization, species integrity can only be maintained through post-zygotic isolating barriers (pibs). pibs need not only be intrinsic (i.e. hybrid inviability and sterility caused by developmental incompatibilities), but also can be extrinsic due to the hybrid's intermediate phenotype falling between the parental niches. for example, in migratory species, hybrid fitness might be reduced as a result of intermediate migration pathways and reaching suboptimal wintering grounds. her ... | 2007 | 17254995 |
| cross-fostering reveals seasonal changes in the relative fitness of two competing species of flycatchers. | spatial and temporal heterogeneity in relative fitness of competing species is a key factor affecting the structure of communities. however, it is not intuitive why species that are ecologically similar should differ in their response to environmental changes. here we show that two sympatric flycatchers differ in reproductive strategy and in sensitivity to harsh environment. the fitness of collared flycatchers (ficedula albicollis), which are dominant in interference competition, is more sensiti ... | 2005 | 17148130 |
| nosy neighbours: large broods attract more visitors. a field experiment in the pied flycatcher, ficedula hypoleuca. | life is uncertain. to reduce uncertainty and make adaptive decisions, individuals need to collect information. individuals often visit the breeding sites of their conspecifics (i.e., "prospect"), likely to assess conspecifics' reproductive success and to use such information to identify high-quality spots for future breeding. we investigated whether visitation rate by prospectors and success of visited sites are causally linked. we manipulated the reproductive success (enlarged, reduced, and con ... | 2017 | 28331976 |
| competitor phenology as a social cue in breeding site selection. | predicting habitat quality is a major challenge for animals selecting a breeding patch, because it affects reproductive success. breeding site selection may be based on previous experience, or on social information from the density and success of competitors with an earlier phenology. variation in animal breeding phenology is often correlated with variation in habitat quality. generally, animals breed earlier in high-quality habitats that allow them to reach a nutritional threshold required for ... | 2017 | 28118482 |
| vitamin profiles in two free-living passerine birds under a metal pollution gradient - a calcium supplementation experiment. | vitamin and carotenoid deficiency may impair development in free-living vertebrates, because of the importance of these micronutrients to growth, antioxidant defense and calcium regulation. micronutrient and calcium insufficiency can be intensified by metal pollution which can interfere with nutrient homeostasis or indirectly reduce food availability. furthermore, absorption of dietary heavy metals is dependent on food calcium and vitamin levels. we investigated the effect of calcium on plasma v ... | 2017 | 28068581 |
| african departure rather than migration speed determines variation in spring arrival in pied flycatchers. | properly timed spring migration enhances reproduction and survival. climate change requires organisms to respond to changes such as advanced spring phenology. pied flycatchers ficedula hypoleuca have become a model species to study such phenological adaptations of long-distance migratory songbirds to climate change, but data on individuals' time schedules outside the breeding season are still lacking. using light-level geolocators, we studied variation in migration schedules across the year in a ... | 2017 | 27726147 |
| telomere damage and redox status alterations in free-living passerines exposed to metals. | telomere length may reflect the expected life span and possibly individual quality. environmental stressors are known to increase oxidative stress and accelerate telomere attrition: however the interactions between redox status and telomere dynamics are not fully understood. we investigated whether exposure to heavy metal pollution is associated with oxidative stress and telomere damage in two insectivorous passerines, the great tit (parus major) and the pied flycatcher (ficedula hypoleuca). we ... | 2017 | 27693158 |
| climate change relaxes the time constraints for late-born offspring in a long-distance migrant. | animals in seasonal environments need to fit their annual-cycle stages, such as moult and migration, in a tight schedule. climate change affects the phenology of organisms and causes advancements in timing of these annual-cycle stages but not necessarily at the same rates. for migratory birds, this can lead to more severe or more relaxed time constraints in the time from fledging to migration, depending on the relative shifts of the different stages. we tested how a shift in hatch date, which ha ... | 2016 | 27655765 |
| natal habitat imprinting counteracts the diversifying effects of phenotype-dependent dispersal in a spatially structured population. | habitat selection may have profound evolutionary consequences, but they strongly depend on the underlying preference mechanism, including genetically-determined, natal habitat and phenotype-dependent preferences. it is known that different mechanisms may operate at the same time, yet their relative contribution to population differentiation remains largely unexplored empirically mainly because of the difficulty of finding suitable study systems. here, we investigate the role of early experience ... | 2016 | 27503506 |
| phenological mismatch and ontogenetic diet shifts interactively affect offspring condition in a passerine. | climate change may cause phenological asynchrony between trophic levels, which can lead to mismatched reproduction in animals. although indirect effects of mismatch on fitness are well described, direct effects on parental prey choice are not. moreover, direct effects of prey variation on offspring condition throughout their early development are understudied. here, we used camera trap data collected over 2 years to study the effects of trophic mismatch and nestling age on prey choice in pied fl ... | 2016 | 27263989 |
| [wulst activation in pied flycatcher nestlings in feeding behavior induced by patterned visual stimulus]. | immunohistochemical detection of c-fos was used to study the transcriptional activation in two higher visual centers (wulst area and entopallium) of 12-day-old pied flycatcher (ficedula hypoleuca) during the realization of feeding behavior guided by patterned visual stimulus, simulating the species-specific one. activation was compared in 4 groups of nestlings. control group was not subjected to any experimental influence. in binocular, right-field (deprivation of the left eye) and left-filed (d ... | 2016 | 27263277 |
| carry-over effects of conditions at the wintering grounds on breeding plumage signals in a migratory bird: roles of phenotypic plasticity and selection. | to understand the consequences of ever-changing environment on the dynamics of phenotypic traits, distinguishing between selection processes and individual plasticity is crucial. we examined individual consistency/plasticity in several male secondary sexual traits expressed during the breeding season (white wing and forehead patch size, uv reflectance of white wing patch and dorsal melanin coloration) in a migratory pied flycatcher (ficedula hypoleuca) population over an 11-year period. furtherm ... | 2016 | 27159261 |
| oxidative stress in early life: associations with sex, rearing conditions, and parental physiological traits in nestling pied flycatchers. | conditions experienced during juvenile development can affect the fitness of an organism. during early life, oxidative stress levels can be particularly high as a result of the increased metabolism and the relatively immature antioxidant system of the individual, and this may have medium- and long-term fitness consequences. here we explore variation in levels of oxidative stress measured during early life in relation to sex, rearing conditions (hatching date and brood size), and parental conditi ... | 2017 | 27082719 |
| alternate non-stop migration strategies of pied flycatchers to cross the sahara desert. | each year more than two billion songbirds cross the sahara, but how they perform this formidable task is largely unknown. using geolocation tracks from 27 pied flycatchers, a nocturnally migrating passerine, we show that most birds made diurnal flights in both autumn and spring. these diurnal flights were estimated to be part of non-stop flights of mostly 40-60 h. in spring, birds flew across the sahara, while autumn migration probably circumpassed part of the desert, through a long oversea flig ... | 2016 | 27072404 |
| predator encounters have spatially extensive impacts on parental behaviour in a breeding bird community. | predation risk has negative indirect effects on prey fitness, partly mediated through changes in behaviour. evidence that individuals gather social information from other members of the population suggests that events in a community may impact the behaviour of distant individuals. however, spatially wide-ranging impacts on individual behaviour caused by a predator encounter elsewhere in a community have not been documented before. we investigated the effect of a predator encounter (hawk model pr ... | 2016 | 27030411 |
| effects of experimental calcium availability and anthropogenic metal pollution on eggshell characteristics and yolk carotenoid and vitamin levels in two passerine birds. | the maternal investment into egg quality depends on the condition of the female, the quality of the mate, and the quality of the environment. in that sense, availability of nutrients and exposure to pollutants are essential parameters to consider. the main aim of this study is to assess the effects of calcium (ca) availability and anthropogenic metal pollution on early-stage reproduction in two passerine species, great tits (parus major) and pied flycatchers (ficedula hypoleuca), inhabiting a ca ... | 2016 | 26943740 |
| effects of calcium supplementation on growth and biochemistry in two passerine species breeding in a ca-poor and metal-polluted area. | several studies provide evidence of calcium (ca)-limited reproduction in birds. a ca-supplementation experiment was carried out in 2014 in a ca-poor area associated with metal pollution in sw finland. we aimed to evaluate the relationship between ca availability and heavy metal exposure in free-living passerines, and to compare ca levels in plasma and feces and the effects of ca supplementation and metals on breeding, nestling growth, and plasma biochemistry in great tits and pied flycatchers. a ... | 2016 | 26856860 |
| species and abundance of ectoparasitic flies (diptera) in pied flycatcher nests in fennoscandia. | birds host several ectoparasitic fly species with negative effects on nestling health and reproductive output, and with the capability of transmitting avian blood parasites. information on the abundance and distribution of the ectoparasitic fly genera ornithomya (hippoboscidae) and protocalliphora (calliphoridae) in northern europe is still generally poor, and we thus explored their geographic range and occurrence of these flies in the nests of a common avian model species, the pied flycatcher f ... | 2015 | 26691851 |
| nest-dwelling ectoparasites reduce antioxidant defences in females and nestlings of a passerine: a field experiment. | ectoparasites may imply a cost in terms of oxidative stress provoked by inflammatory responses in hosts. ectoparasites may also result in costs for nestlings and brooding females because of the direct loss of nutrients and reduced metabolic capacity resulting from parasite feeding activities. these responses may involve the production of reactive oxygen and nitrogen species that may induce oxidative damage in host tissues. our goal was to examine the effect of ectoparasites in terms of oxidative ... | 2015 | 25920904 |
| natural selection for earlier male arrival to breeding grounds through direct and indirect effects in a migratory songbird. | for migratory birds, the earlier arrival of males to breeding grounds is often expected to have fitness benefits. however, the selection differential on male arrival time has rarely been decomposed into the direct effect of male arrival and potential indirect effects through female traits. we measured the directional selection differential on male arrival time in the pied flycatcher (ficedula hypoleuca) using data from 6 years and annual number of fledglings as the fitness proxy. using structura ... | 2015 | 25859326 |
| effects of spring temperatures on the strength of selection on timing of reproduction in a long-distance migratory bird. | climate change has differentially affected the timing of seasonal events for interacting trophic levels, and this has often led to increased selection on seasonal timing. yet, the environmental variables driving this selection have rarely been identified, limiting our ability to predict future ecological impacts of climate change. using a dataset spanning 31 years from a natural population of pied flycatchers (ficedula hypoleuca), we show that directional selection on timing of reproduction inte ... | 2015 | 25848856 |
| effects of nocturnal illumination on life-history decisions and fitness in two wild songbird species. | the effects of artificial night lighting on animal behaviour and fitness are largely unknown. most studies report short-term consequences in locations that are also exposed to other anthropogenic disturbance. we know little about how the effects of nocturnal illumination vary with different light colour compositions. this is increasingly relevant as the use of led lights becomes more common, and led light colour composition can be easily adjusted. we experimentally illuminated previously dark na ... | 2015 | 25780240 |
| long-term recovery of clutch size and egg shell quality of the pied flycatcher (ficedula hypoleuca) in a metal polluted area. | we explored if breeding parameters and egg shell quality of an insectivorous passerine, pied flycatcher ficedula hypoleuca, have fully recovered after c.a. 99% decrease in dust emissions from a non-ferrous smelter in the course of the 23 year study period. some potentially important population characteristics (density, phenology, age) and environmental variables (habitat, inter-specific competition) were taken into account in the analysis. we found marked increase in reproductive parameters (egg ... | 2015 | 25756228 |
| [visual input affects the expression of the early genes c-fos and zenk in auditory telencephalic centers of pied flycatcher nestlings during the acoustically-guided freezing]. | the present study analyzed expression of transcriptional factors c-fos and zenk in 9-day-old pied flycatcher nestlings' (ficedula hypoleuca) telencephalic auditory centers (field l, caudomedial nidopallium and caudomedial mesopallium) involved in the acoustically-guided defense behavior. species-typical alarm call was presented to the young in three groups: 1--intact group (sighted control), 2--nestlings visually deprived just before the experiment for a short time (unsighted control) 3--nestlin ... | 2015 | 25723019 |
| temporal trends in metal pollution: using bird excrement as indicator. | past mining and smelting activities have resulted in metal polluted environments all over the world, but long-term monitoring data is often scarce, especially in higher trophic levels. in this study we used bird (parus major and ficedula hypoleuca) excrement to monitor metal pollution in the terrestrial environment following 16 years of continuously reduced emissions from a copper/nickel smelter in finland. in the early 1990s, lead and cadmium concentrations dropped significantly in excrement, b ... | 2015 | 25680108 |
| manipulation of parental effort affects plumage bacterial load in a wild passerine. | it has been suggested that plumage microorganisms play an important role in shaping the life histories of wild birds. some bacteria may act as pathogens or cause damage to feathers, and thereby reduce individual fitness. intense parental care in birds can result in a reduction of self-maintenance and preening behavior in parents and therefore might affect the dynamics of microbiota living on their feathers. however, experimental evidence of this relationship is virtually absent. we manipulated t ... | 2015 | 25663331 |
| a review on exposure and effects of arsenic in passerine birds. | arsenic (as) is a metalloid of high concern because of its toxic effects for plants and animals. however, it is hard to find information on this metalloid in passerines. this review presents a comprehensive overview of as exposure and effects in birds, and more particularly in passerines, as a result of an extensive search of the literature available. internal tissues are the most frequently analyzed matrices for as determination in passerines (37.5% of the reviewed studies used internal tissues ... | 2015 | 25644847 |
| [cardioelectrical field on the body surface of newborn nestlings of the pied flycatcher (ficedula hypoleuca) at the period of initial atrial activity]. | by electrocardiotopographic method the dynamics of electrical field has been studied on the body surface of newborn nestlings of the pied flycatcher (ficedula hypoleuca) at the period of atrial depolarization. on the body surface there have been revealed two shifts of zones of positive and negative cardiopotentials of the heart electrical field, which are due to peculiarities of sequence of atrial depolarization, anatomical immaturity of atrial structures. and the oresence of closed foramen oval ... | 2014 | 25508939 |
| [cardioelectrical field on the body surface of newborn nestlings of the pied flycatcher (ficedula hypoleuca) at the period of initial atrial activity]. | by electrocardiotopographic method the dynamics of electrical field has been studied on the body surface of newborn nestlings of the pied flycatcher (ficedula hypoleuca) at the period of atrial depolarization. on the body surface there have been revealed two shifts of zones of positive and negative cardiopotentials of the heart electrical field, which are due to peculiarities of sequence of atrial depolarization, anatomical immaturity of atrial structures. and the oresence of closed foramen oval ... | 2014 | 25486808 |
| snail consumption and breeding performance of pied flycatchers (ficedula hypoleuca) along a pollution gradient in the middle urals, russia. | during the years 1989-91, 1997-2003, and 2005-07, we studied how emissions from the middle urals copper smelter affect snail availability and reproduction of free-living pied flycatchers (ficedula hypoleuca). we counted snail shells dropped in nests and analysed food samples of nestlings. pied flycatchers brought to nestlings fewer shells in heavily polluted sites compared to background sites, resulting in reduced ca intake. species diversity of snails collected by birds decreased with decreasin ... | 2014 | 24846405 |
| heterospecific female mimicry in ficedula flycatchers. | mimicry is a widespread phenomenon. vertebrate visual mimicry often operates in an intraspecific sexual context, with some males resembling conspecific females. pied flycatcher (ficedula hypoleuca) dorsal plumage varies from the ancestral black to female-like brown. experimental studies have shown that conspecific and heterospecific (collared flycatcher, f. albicollis) individuals of both sexes respond, at least initially, to brown individuals as if they were female. we quantified the perceptual ... | 2014 | 24494669 |
| nonrandom dispersal drives phenotypic divergence within a bird population. | gene flow through dispersal has traditionally been thought to function as a force opposing evolutionary differentiation. however, directional gene flow may actually reinforce divergence of populations in close proximity. this study documents the phenotypic differentiation over more than two decades in body size (tarsus length) at a very short spatial scale (1.1 km) within a population of pied flycatchers ficedula hypoleuca inhabiting deciduous and coniferous habitats. unlike females, males breed ... | 2013 | 24363908 |
| differentiation in neutral genes and a candidate gene in the pied flycatcher: using biological archives to track global climate change. | global climate change is one of the major driving forces for adaptive shifts in migration and breeding phenology and possibly impacts demographic changes if a species fails to adapt sufficiently. in western europe, pied flycatchers (ficedula hypoleuca) have insufficiently adapted their breeding phenology to the ongoing advance of food peaks within their breeding area and consequently suffered local population declines. we address the question whether this population decline led to a loss of gene ... | 2013 | 24363905 |
| fitness consequences of northward dispersal as possible adaptation to climate change, using experimental translocation of a migratory passerine. | climate change leads to rapid, differential changes in phenology across trophic levels, often resulting in temporal mismatches between predators and their prey. if a species cannot easily adjust its timing, it can adapt by choosing a new breeding location with a later phenology of its prey. in this study, we experimentally investigated whether long-distance dispersal to northern breeding grounds with a later phenology could be a feasible process to restore the match between timing of breeding an ... | 2013 | 24349454 |
| natal dispersal based on past and present environmental phenology in the pied flycatcher (ficedula hypoleuca). | natal dispersal allows individuals to reach suitable breeding sites. the effect of present plant phenology as a cue for dispersal into areas with favourable stages of development has been well established across avian and mammalian taxa. however, the effect of past experience is less understood. we studied the effect of past and present phenology of the environment on the direction and distance of natal dispersal in a passerine bird, the pied flycatcher (ficedula hypoleuca). we monitored spring ... | 2014 | 24297099 |
| large-scale geographical variation in eggshell metal and calcium content in a passerine bird (ficedula hypoleuca). | birds have been used as bioindicators of pollution, such as toxic metals. levels of pollutants in eggs are especially interesting, as developing birds are more sensitive to detrimental effects of pollutants than adults. only very few studies have monitored intraspecific, large-scale variation in metal pollution across a species' breeding range. we studied large-scale geographic variation in metal levels in the eggs of a small passerine, the pied flycatcher (ficedula hypoleuca), sampled from 15 p ... | 2014 | 24234761 |
| observed fitness may affect niche overlap in competing species via selective social information use. | social information transmission is important because it enables horizontal spread of behaviors, not only between conspecifics but also between individuals of different species. because interspecific social information use is expected to take place among species with similar resource needs, it may have major consequences for the emergence of local adaptations, resource sharing, and community organization. social information use is expected to be selective, but the conditions promoting it in an in ... | 2013 | 24021400 |
| malaria infections reinforce competitive asymmetry between two ficedula flycatchers in a recent contact zone. | parasites may influence the outcome of interspecific competition between closely related host species through lower parasite virulence in the host with which they share the longer evolutionary history. we tested this idea by comparing the prevalence of avian malaria (haemosporidia) lineages and their association with survival in pied and collared flycatchers (ficedula hypoleuca and f. albicollis) breeding in a recent contact zone on the swedish island of öland. a nested pcr protocol amplifying h ... | 2013 | 23980765 |
| variation in prevalence and intensity of two avian ectoparasites in a polluted area. | we counted the numbers of pupae of two ectoparasitic flies (protocalliphora sp. and ornithomyia sp.) in the nests of a passerine bird, the pied flycatcher (ficedula hypoleuca) to find out if their prevalence or intensity are affected by long-term environmental pollution by a copper smelter and whether such an interaction would have impacts on birds' breeding success. fecal metal concentrations of f. hypoleuca nestlings were used to explore direct association between metal levels and parasite pre ... | 2013 | 23919991 |
| diet composition as a cause of different contaminant exposure in two sympatric passerines in the middle urals, russia. | contaminant exposure can vary between species but primary causes of it are often unclear. in order to estimate heavy metal intake of two sympatric passerines - ficedula hypoleuca pall. and parus ater l. - we studied nestling diet and metal concentrations in prey invertebrates, near the middle ural copper smelter and in an unpolluted area. diet of p. ater contained more cu, cd and zn compared to f. hypoleuca and the same amount of pb. contribution of different prey taxa to bird metal intake was n ... | 2013 | 23916013 |
| the excuse principle can maintain cooperation through forgivable defection in the prisoner's dilemma game. | reciprocal altruism describes a situation in which an organism acts in a manner that temporarily reduces its fitness while increasing another organism's fitness, but there is an ultimate fitness benefit based on an expectation that the other organism will act in a similar manner at a later time. it creates the obvious dilemma in which there is always a short-term benefit to cheating, therefore cooperating individuals must avoid being exploited by non-cooperating cheaters. this is achieved by fol ... | 2013 | 23864603 |
| lifetime fitness and age-related female ornament signalling: evidence for survival and fecundity selection in the pied flycatcher. | ornaments displayed by females have often been denied evolutionary interest due to their frequently reduced expression relative to males, habitually attributed to a genetic correlation between the sexes. we estimated annual and lifetime reproductive success of female pied flycatchers (ficedula hypoleuca) and applied capture-mark-recapture models to analyse annual survival rates in relation to the patterns of expression (absence/presence) of an ornament displayed by all males and a fraction of fe ... | 2013 | 23638705 |
| low fertility of wild hybrid male flycatchers despite recent divergence. | postzygotic isolation may be important for maintaining species boundaries, particularly when premating barriers are incomplete. little is known about the course of events leading from minor environmental mismatches affecting hybrid fitness to severe genetic incompatibilities causing sterility or inviability. we investigated whether reduced reproductive success of hybrid males was caused by suboptimal sperm traits or by more severe genetic incompatibilities in a hybrid zone of pied (ficedula hypo ... | 2013 | 23576780 |
| fluctuating selection and immigration as determinants of the phenotypic composition of a population. | it is important to identify the factors that affect the evolutionary potential of populations to respond to environmental changes. such processes are for example the ones affecting the amount of heritable phenotypic variation in a population. we examined factors explaining the wide phenotypic variation in the genetically determined black-brown dorsal colouration of male pied flycatchers (ficedula hypoleuca) during a period of >50 years in a northern european breeding population. we demonstrate t ... | 2013 | 23361152 |
| you mob my owl, i'll mob yours: birds play tit-for-tat game. | reciprocity is fundamental to cooperative behaviour and has been verified in theoretical models. however, there is still limited experimental evidence for reciprocity in non-primate species. our results more decisively clarify that reciprocity with a tit-for-tat enforcement strategy can occur among breeding pied flycatchers ficedula hypoleuca separate from considerations of byproduct mutualism. breeding pairs living in close proximity (20-24 m) did exhibit byproduct mutualism and always assisted ... | 2012 | 23150772 |
| [specific immunity and polymorphism of breeding plumage in pied flycatcher (ficedula hypoleuca) males (aves: passeriformes)]. | the relationship between the type of melanin-based plumage coloration and the strength of experimentally induced immune response was studied using as an example a pied flycatcher population from the moscow region. the plumage of pied flycatcher males exhibits the full spectrum of transitions from contrasting black-and-white to cryptic brownish, the latter being very similar to the coloration of females. in spite of numerous studies, the nature of this polymorphism still remains vague. unlike man ... | 2012 | 23136790 |
| the proteomics of feather development in pied flycatchers (ficedula hypoleuca) with different plumage coloration. | the genetic theory of morphological evolution postulates that form evolves largely by changing the expression proteins that are functionally conserved. it follows that understanding the function of proteins during different phases of development as well as the mechanisms by which the functions are modified is a prerequisite for understanding evolutionary change. male pied flycatchers exhibit marked phenotypic variation in their breeding plumage. this variation has repeatedly been shown to have a ... | 2012 | 23110392 |
| decreased metal accumulation in passerines as a result of reduced emissions. | technological advances in industrial processes have resulted in reduced atmospheric emissions from metal industries all over the globe, but the response of the environment is not well known. the authors studied metal (as, cd, cu, ni, pb, and se) accumulation in passerine birds (pied flycatcher, ficedula hypoleuca, and great tit, parus major) following almost 20 years of reduced metal emissions from the largest nonferrous smelter in finland. close to the industry, emission reductions resulted in ... | 2012 | 22513991 |
| higher nest predation risk in association with a top predator: mesopredator attraction? | breeding close to top predators is a widespread reproductive strategy. breeding animals may gain indirect benefits if proximity to top predators results in a reduction of predation due to suppression of mesopredators. we tested if passerine birds gain protection from mesopredators by nesting within territories of a top predator, the ural owl (strix uralensis). we placed nest boxes for pied flycatchers (ficedula hypoleuca) in ural owl nest sites and in control sites (currently unoccupied by owls) ... | 2012 | 22492168 |
| no evidence for pre-copulatory sexual selection on sperm length in a passerine bird. | there is growing evidence that post-copulatory sexual selection, mediated by sperm competition, influences the evolution of sperm phenotypes. evidence for pre-copulatory sexual selection effects on sperm traits, on the other hand, is rather scarce. a recent paper on the pied flycatcher, ficedula hypoleuca, reported phenotypic associations between sperm length and two sexually selected male traits, i.e. plumage colour and arrival date, thus invoking pre-copulatory sexual selection for longer sper ... | 2012 | 22384277 |
| climate change, breeding date and nestling diet: how temperature differentially affects seasonal changes in pied flycatcher diet depending on habitat variation. | 1. climate warming has led to shifts in the seasonal timing of species. these shifts can differ across trophic levels, and as a result, predator phenology can get out of synchrony with prey phenology. this can have major consequences for predators such as population declines owing to low reproductive success. however, such trophic interactions are likely to differ between habitats, resulting in differential susceptibility of populations to increases in spring temperatures. a mismatch between bre ... | 2012 | 22356622 |
| an eco-evolutionary model for demographic and phenological responses in migratory birds. | many migratory birds have changed their timing of arrival at breeding grounds in response to recent climate change. understanding the adaptive value and the demographic consequences of these shifts are key challenges. to address these questions we extend previous models of phenological adaptation to climate change under territory competition to include feedback from population dynamics, winter survival and habitat productivity. we study effects of improved pre-breeding survival and of earlier fo ... | 2012 | 24832512 |
| geographical variation in egg mass and egg content in a passerine bird. | reproductive, phenotypic and life-history traits in many animal and plant taxa show geographic variation, indicating spatial variation in selection regimes. maternal deposition to avian eggs, such as hormones, antibodies and antioxidants, critically affect development of the offspring, with long-lasting effects on the phenotype and fitness. little is however known about large-scale geographical patterns of variation in maternal deposition to eggs. we studied geographical variation in egg compone ... | 2011 | 22110579 |
| yolk hormones and sexual conflict over parental investment in the pied flycatcher. | female birds might be able to manipulate the parental effort of their male partner through elevated transfer of hormones to the eggs, since these hormones affect many chick traits that males might use as cues for adjusting the level of their investment. we experimentally studied whether female pied flycatchers ficedula hypoleuca could manipulate male investment via yolk androgens. there is much more variation in yolk androgen levels between females than within clutches, and in order to change th ... | 2011 | 22081740 |
| candidate genes for colour and vision exhibit signals of selection across the pied flycatcher (ficedula hypoleuca) breeding range. | the role of natural selection in shaping adaptive trait differentiation in natural populations has long been recognized. determining its molecular basis, however, remains a challenge. here, we search for signals of selection in candidate genes for colour and its perception in a passerine bird. pied flycatcher plumage varies geographically in both its structural and pigment-based properties. both characteristics appear to be shaped by selection. a single-locus outlier test revealed 2 of 14 loci t ... | 2012 | 22027894 |
| slow improvements of metal exposure, health- and breeding conditions of pied flycatchers (ficedula hypoleuca) after decreased industrial heavy metal emissions. | the environment around metal industries, such as smelters, is often highly contaminated due to continuous deposition of metals. we studied nest box breeding populations of pied flycatchers (ficedula hypoleuca) in a well-studied pollution gradient from a sulfide ore smelter in northern sweden, after reduced aerial metal emissions (by 93-99%) from the smelter. the deposition of arsenic, cadmium, copper and zinc (based on moss samples) reflected the reduced emissions fairly well. however, nestling ... | 2011 | 21788063 |
| species- and age-related variation in metal exposure and accumulation of two passerine bird species. | we measured the concentration of several elements (arsenic [as], calcium [ca], cadmium [cd], copper [cu], nickel [ni], lead [pb], selenium [se] and zinc [zn]) in adult and nestling pied flycatchers (ficedula hypoleuca) and great tits (parus major) at different distances to a cu-ni smelter in 2009. feces of nestlings generally failed to correspond with internal element concentrations but reflected the pollution exposure, indicating an increased stress by removal of excess metals. the uptake of cu ... | 2011 | 21783288 |
| digit ratios have poor indicator value in a wild bird population. | early androgen exposure is known to have long-lasting effects on phenotype, behaviour and even fitness, but difficulties in measuring the exposure hinders the study of its importance in evolutionary context. digit ratios have been highlighted as a potential easy-to-measure indicator of early steroid exposure, as they have been suggested to reflect steroid, mainly testosterone levels during prenatal development. however, evidence for digit ratios reflecting early steroid levels is weak, as experi ... | 2011 | 21625648 |
| prevalence of salmonella and yersinia in free-living pied flycatchers (ficedula hypoleuca) in central spain. | salmonella and yersinia are important enteropathogens in poultry and can affect birds of all ages, including embryos. these food-borne zoonotic enteropathogens are of great economic and medical concern worldwide and are intensely studied in poultry. information regarding the prevalence of these bacteria in wild birds is scarce and biased toward avian species ecologically linked to humans, which have often been incriminated as both reservoirs and disseminators of these enteropathogens. the preval ... | 2011 | 22946412 |