| bottom of the heap: having heavier competitors accelerates early-life telomere loss in the european starling, sturnus vulgaris. | early-life adversity is associated with poorer health and survival in adulthood in humans and other animals. one pathway by which early-life environmental stressors could affect the adult phenotype is via effects on telomere dynamics. several studies have shown that early-life adversity is associated with relatively short telomeres, but these are often cross-sectional and usually correlational in design. here, we present a novel experimental system for studying the relationship between early-lif ... | 2013 | 24386235 |
| site-specific regulation of adult neurogenesis by dietary fatty acid content, vitamin e and flight exercise in european starlings. | exercise is known to have a strong effect on neuroproliferation in mammals ranging from rodents to humans. recent studies have also shown that fatty acids and other dietary supplements can cause an upregulation of neurogenesis. it is not known, however, how exercise and diet interact in their effects on adult neurogenesis. we examined neuronal recruitment in multiple telencephalic sites in adult male european starlings (sturnus vulgaris) exposed to a factorial combination of flight exercise, die ... | 2014 | 24372878 |
| estimation of unsteady aerodynamics in the wake of a freely flying european starling (sturnus vulgaris). | wing flapping is one of the most widespread propulsion methods found in nature; however, the current understanding of the aerodynamics in bird wakes is incomplete. the role of the unsteady motion in the flow and its contribution to the aerodynamics is still an open question. in the current study, the wake of a freely flying european starling has been investigated using long-duration high-speed particle image velocimetry (piv) in the near wake. kinematic analysis of the wings and body of the bird ... | 2013 | 24278243 |
| long-distance dispersal maximizes evolutionary potential during rapid geographic range expansion. | conventional wisdom predicts that sequential founder events will cause genetic diversity to erode in species with expanding geographic ranges, limiting evolutionary potential at the range margin. here, we show that invasive european starlings (sturnus vulgaris) in south africa preserve genetic diversity during range expansion, possibly as a result of frequent long-distance dispersal events. we further show that unfavourable environmental conditions trigger enhanced dispersal, as indicated by sig ... | 2013 | 24192018 |
| ambient temperature influences birds' decisions to eat toxic prey. | aposematic prey warn predators of their toxicity using conspicuous signals. however, predators regularly include aposematic prey in their diets, particularly when they are in a poor energetic state and in need of nutrients. we investigated whether or not an environmental factor, ambient temperature, could change the energetic state of predators and lead to an increased intake of prey that they know to contain toxins. we found that european starlings, sturnus vulgaris, increased their consumption ... | 2013 | 24109148 |
| european starlings ( sturnus vulgaris ) suggest that landfills are an important source of bioaccumulative flame retardants to canadian terrestrial ecosystems. | landfills are used as the primary means for the disposal of municipal solid waste in canada. in the present study, polybrominated diphenyl ethers (pbdes) and other flame retardants (frs) were determined in fresh european starling ( sturnus vulgaris ) eggs collected in 2009, 2010, and 2011 from nest boxes established within, adjacent to, and 10 and 40 km distant to five major urban centers across canada, i.e., vancouver, british columbia (bc); calgary, alberta (ab); hamilton, ontario (on); montré ... | 2013 | 24059974 |
| estradiol differentially affects auditory recognition and learning according to photoperiodic state in the adult male songbird, european starling (sturnus vulgaris). | changes in hormones can affect many types of learning in vertebrates. adults experience fluctuations in a multitude of hormones over a temporal scale, from local, rapid action to more long-term, seasonal changes. endocrine changes during development can affect behavioral outcomes in adulthood, but how learning is affected in adults by hormone fluctuations experienced during adulthood is less understood. previous reports have implicated the sex steroid hormone estradiol (e2) in both male and fema ... | 2013 | 24058881 |
| effect of head turns on the localization accuracy of sounds in the european starling (sturnus vulgaris). | long signal durations that represent closed-loop conditions permit responses based on the sensory feedback during the presentation of the stimulus, while short stimulus durations that represent open-loop conditions do not allow for directed head turns during signal presentation. a previous study showed that for broadband noise stimuli, the minimum audible angle (maa) of the european starling (sturnus vulgaris) is smaller under closed-loop compared to open-loop conditions (feinkohl & klump, 2013) ... | 2013 | 24035879 |
| the direct response of the gonads to cues of stress in a temperate songbird species is season-dependent. | the gonadotropin releasing hormone (gnrh) system in the hypothalamus is often considered the final point in integration of environmental cues as they pertain to the reproductive axis. however, cues such as stress and food availability are detectable in the plasma (as glucocorticoid and metabolic fuel fluctuations). vertebrate gonads express glucocorticoid receptor, therefore we hypothesized that the gonads can detect and respond directly to cues of stress. we provide evidence here that, in addit ... | 2013 | 24024084 |
| hand rearing affects emotional responses but not basic cognitive performance in european starlings. | hand rearing is a common procedure in behavioural research on birds. while likely to produce tamer experimental animals, there is a risk that it could induce pathological changes in brain and behaviour similar to those seen in mammals that have experienced maternal separation. we explored the effects of hand rearing on the cognitive and behavioural development of european starlings, sturnus vulgaris, to assess the generality of results obtained from hand-reared animals. two groups of age-matched ... | 2013 | 23888084 |
| predators' decisions to eat defended prey depend on the size of undefended prey. | predators that have learned to associate warning coloration with toxicity often continue to include aposematic prey in their diet in order to gain the nutrients and energy that they contain. as body size is widely reported to correlate with energetic content, we predicted that prey size would affect predators' decisions to eat aposematic prey. we used a well-established system of wild-caught european starlings, sturnus vulgaris, foraging on mealworms, tenebrio molitor, to test how the size of un ... | 2013 | 23814280 |
| curvilinear relationships between mu-opioid receptor labeling and undirected song in male european starlings (sturnus vulgaris). | female-directed communication in male songbirds has been reasonably well studied; yet, relatively little is known about communication in other social contexts. songbirds also produce song that is not clearly directed towards another individual (undirected song) when alone or in flocks. although the precise functions of undirected song may differ across species, this type of song is considered important for flock maintenance, song learning or practice. past studies show that undirected song is ti ... | 2013 | 23774651 |
| context-dependent preferences in starlings: linking ecology, foraging and choice. | foraging animals typically encounter opportunities that they either pursue or skip, but occasionally meet several alternatives simultaneously. behavioural ecologists predict preferences using absolute properties of each option, while decision theorists focus on relative evaluations at the time of choice. we use european starlings (sturnus vulgaris) to integrate ecological reasoning with decision models, linking and testing hypotheses for value acquisition and choice mechanism. we hypothesise tha ... | 2013 | 23705019 |
| use of dairies by postreproductive flocks of european starlings. | knowledge of the behavior and movement patterns of european starlings (sturnus vulgaris l.) is important to wildlife managers that seek to resolve conflicts at livestock facilities. we captured and radio tagged 10 starlings at each of 5 dairies in northeastern ohio. from september 19 to october 31, 2007, we obtained sufficient data from 40 birds to study their behavior and movements. the birds visited the dairies where they were initially captured (home sites) on 85% of the days, spending 58% of ... | 2013 | 23684017 |
| photoperiod-dependent regulation of gonadotropin-releasing hormone 1 messenger ribonucleic acid levels in the songbird brain. | annual changes in day length induce marked changes in reproductive function in temperate zone vertebrates. in many avian species, in contrast to other seasonally breeding animals, plasticity in hypothalamic gonadotropin-releasing hormone - 1 (gnrh1) expression rather than (or in addition to) release governs changes in pituitary-gonadal activity. investigations of the cellular and molecular mechanisms that govern gnrh1 plasticity were previously hindered by a collective inability of scientists in ... | 2013 | 23660447 |
| testicular growth and regression are not correlated with dio2 expression in a wild male songbird, sturnus vulgaris, exposed to natural changes in photoperiod. | timing of seasonal breeding in birds and mammals is regulated by changing the day length and is dependent on the presence of thyroid hormones. a mechanism for thyroid-dependent control of seasonality has been proposed, in which exposure to long day lengths induces rapid local conversion of t4 to its bioactive form, t3, via the up-regulation of the enzyme type 2 iodothyronine deiodinase (dio2) in the brain, and the down-regulation of dio3 (which inactivates t3). such changes were correlated with ... | 2013 | 23525217 |
| links between breeding readiness, opioid immunolabeling, and the affective state induced by hearing male courtship song in female european starlings (sturnus vulgaris). | male courtship vocalizations represent a potent signal designed to attract females; however, not all females find male signals equally attractive. we explored the possibility that the affective state induced by hearing courtship vocalizations depends on the motivational state of a receiver. we used a conditioned place preference test of reward to determine the extent to which the rewarding properties of hearing male courtship song differed in female european starlings categorized as nest box own ... | 2013 | 23473880 |
| diffusion of individual birds in starling flocks. | flocking is a paradigmatic example of collective animal behaviour, where global order emerges out of self-organization. each individual has a tendency to align its flight direction with those of neighbours, and such a simple form of interaction produces a state of collective motion of the group. when compared with other cases of collective ordering, a crucial feature of animal groups is that the interaction network is not fixed in time, as each individual moves and continuously changes its neigh ... | 2013 | 23407827 |
| starlings uphold principles of economic rationality for delay and probability of reward. | rationality principles are the bedrock of normative theories of decision-making in biology and microeconomics, but whereas in microeconomics, consistent choice underlies the notion of utility; in biology, the assumption of consistent selective pressures justifies modelling decision mechanisms as if they were designed to maximize fitness. in either case, violations of consistency contradict expectations and attract theoretical interest. reported violations of rationality in non-humans include int ... | 2013 | 23390098 |
| artificial rain and cold wind act as stressors to captive molting and non-molting european starlings (sturnus vulgaris). | free-roaming animals continually cope with changes in their environment. one of the most unpredictable environmental phenomena is weather. being able to respond to weather appropriately is crucial as it can be a threat to survival. the stress response, consisting of increases in heart rate and release of glucocorticoids, is an important mechanism by which animals cope with stressors. this study examined behavioral, heart rate, and corticosterone responses of captive european starlings (sturnus v ... | 2013 | 23277223 |
| azimuthal sound localization in the european starling (sturnus vulgaris): ii. psychophysical results. | small songbirds have a difficult analysis problem: their head is small compared to the wavelengths of sounds used for communication providing only small interaural time and level differences. klump and larsen (1992) measured the physical binaural cues in the european starling (sturnus vulgaris) that allow the comparison of acoustical cues and perception. we determined the starling's minimum audible angle (maa) in an operant go/nogo procedure for different spectral and temporal stimulus condition ... | 2013 | 23160796 |
| sharing mates and nest boxes is associated with female "friendship" in european starlings, sturnus vulgaris. | breeding decisions in birds involve both mate and nest choice, and there is increasing evidence that social influences may modulate individual choices. female preferences may be affected by other females' preferences and mutual choice cannot always be excluded, which makes the whole pattern more complex than assumed by most sexual selection models. social transmission may be facilitated by particular social bonds, therefore prebreeding social networks may influence later mate choices. the other ... | 2013 | 23106801 |
| emergence of selectivity and tolerance in the avian auditory cortex. | the ability to recognize auditory objects like words and bird songs is thought to depend on neural responses that are selective between categories of the objects and tolerant of variation within those categories. to determine whether a hierarchy of increasing selectivity and tolerance exists in the avian auditory system, we trained european starlings (sturnus vulgaris) to differentially recognize sets of songs, then measured extracellular single unit responses under urethane anesthesia in six ar ... | 2012 | 23100437 |
| context-dependent links between song production and opioid-mediated analgesia in male european starlings (sturnus vulgaris). | little is known about the neural mechanisms that ensure appropriate vocal behaviors within specific social contexts. male songbirds produce spontaneous (undirected) songs as well as female-directed courtship songs. opioid neuropeptide activity in specific brain regions is rewarding, at least in mammals, and past studies suggest that the opioid met-enkephalin in such areas is more tightly linked to undirected than female-directed song. recent data using a song-associated place preference paradigm ... | 2012 | 23056422 |
| testosterone increases repertoire size in an open-ended learner: an experimental study using adult male european starlings (sturnus vulgaris). | song in songbirds is a learned secondary sexual behavior, first acquired during a sensitive phase of juvenile development, which is affected by hormones such as testosterone (t). while the latter has received much attention, the potential involvement of t in the adult repertoire changes observed in a number of species is much less understood. yet, this may prove essential to understand the role of song as a sexually selected trait. we therefore performed a t-implantation experiment during the no ... | 2012 | 23036784 |
| influence of testosterone metabolites on song-control system neuroplasticity during photostimulation in adult european starlings (sturnus vulgaris). | the song-control system is a network of discrete nuclei in the songbird brain that controls the production and learning of birdsong and exhibits some of the best-studied neuroplasticity found in the adult brain. photoperiodic growth of the song-control system during the breeding season is driven, at least in part, by the gonadal steroid testosterone. when acting on neural tissue, however, testosterone can be metabolized into 5α-dihydrotestosterone (dht) or 17β-estradiol (e2), which activate diff ... | 2012 | 22792214 |
| non-breeding song rate reflects nutritional condition rather than body condition. | numerous studies have focused on song in songbirds as a signal involved in mate choice and intrasexual competition. it is expected that song traits such as song rate reflect individual quality by being dependent on energetic state or condition. while seasonal variation in bird song (i.e., breeding versus non-breeding song) and its neural substrate have received a fair amount of attention, the function and information content of song outside the breeding season is generally much less understood. ... | 2012 | 22590563 |
| experimental analysis of perching in the european starling (sturnus vulgaris: passeriformes; passeres), and the automatic perching mechanism of birds. | the avian automatic perching mechanism (apm) involves the automatic digital flexor mechanism (adfm) and the digital tendon-locking mechanism (dtlm). when birds squat on a perch to sleep, the increased tendon travel distance due to flexion of the knee and ankle supposedly causes the toes to grip the perch (adfm) and engage the dtlm so perching while sleeping involves no muscular effort. however, the knees and ankles of sleeping european starlings (sturnus vulgaris) are only slightly flexed and, e ... | 2012 | 22539208 |
| constitutive immune function in european starlings, sturnus vulgaris, is decreased immediately after an endurance flight in a wind tunnel. | life-history theory predicts that animals face a trade-off in energy allocation between performing strenuous exercise, such as migratory flight, and mounting an immune response. we experimentally tested this prediction by studying immune function in european starlings, sturnus vulgaris, flown in a wind tunnel. specifically, we predicted that constitutive immune function decreases in response to training and, additionally, in response to immediate exercise. we compared constitutive immune functio ... | 2012 | 22189771 |
| the development of stereotypic behavior in caged european starlings, sturnus vulgaris. | stereotypic behavior in captive animals has been hypothesized to emerge from thwarted natural behavior patterns and is thought to be more common in captive-reared animals. however, data on the early stages of developing stereotypies are currently scarce. we compared the development of stereotypic route-tracing and somersaulting in hand-reared and wild-caught starlings placed in individual cages for the first time. we found that wild-caught birds were less active but showed more escape motivation ... | 2012 | 22127904 |
| effects of auditory recognition learning on the perception of vocal features in european starlings (sturnus vulgaris). | learning to recognize complex sensory signals can change the way they are perceived. european starlings (sturnus vulgaris) recognize other starlings by their song, which consists of a series of complex, stereotyped motifs. song recognition learning is accompanied by plasticity in secondary auditory areas, suggesting that perceptual learning is involved. here, to investigate whether perceptual learning can be observed behaviorally, a same-different operant task was used to measure how starlings p ... | 2011 | 22087940 |
| sexual dimorphism and bilateral asymmetry of syrinx and vocal tract in the european starling (sturnus vulgaris). | sexually dimorphic vocal behavior in zebra finches (taeniopygia guttata) is associated with a 100% larger syrinx in males and other morphological adaptations of the sound source. the songbird syrinx consists of two independent sound sources, whose specialization for different spectral ranges may be reflected in morphological properties, but the morphology of labia and syringeal skeleton have not been investigated for lateralized specializations. similarly, little is known whether the morphology ... | 2011 | 22076959 |
| cognitive mechanisms of risky choice: is there an evaluation cost? | we contrast two classes of choice processes, those assuming time-consuming comparisons and those where stimuli for each option act independently, competing for expression by cross censorship. the sequential choice model (scm) belongs in the latter category, and has received empirical support in several procedures involving deterministic alternatives. here we test this model in risky choices. in two treatments, each with five conditions, european starlings (sturnus vulgaris) faced choices between ... | 2012 | 22001371 |
| individual differences in the motivation to communicate relate to levels of midbrain and striatal catecholamine markers in male european starlings. | individuals display dramatic differences in social communication even within similar social contexts. across vertebrates dopaminergic projections from the ventral tegmental area (vta) and midbrain central gray (gct) strongly influence motivated, reward-directed behaviors. norepinephrine is also rich in these areas and may alter dopamine neuronal activity. the present study was designed to provide insight into the roles of dopamine and norepinephrine in vta and gct and their efferent striatal tar ... | 2011 | 21907203 |
| migration- and exercise-induced changes to flight muscle size in migratory birds and association with igf1 and myostatin mrna expression. | seasonal adjustments to muscle size in migratory birds may result from preparatory physiological changes or responses to changed workloads. the mechanisms controlling these changes in size are poorly understood. we investigated some potential mediators of flight muscle size (myostatin and insulin-like growth factor, igf1) in pectoralis muscles of wild wintering or migrating white-throated sparrows (zonotrichia albicollis), captive white-throated sparrows that were photoperiod manipulated to be i ... | 2011 | 21832125 |
| some causes of the variable shape of flocks of birds. | flocks of birds are highly variable in shape in all contexts (while travelling, avoiding predation, wheeling above the roost). particularly amazing in this respect are the aerial displays of huge flocks of starlings (sturnus vulgaris) above the sleeping site at dawn. the causes of this variability are hardly known, however. here we hypothesise that variability of shape increases when there are larger local differences in movement behaviour in the flock. we investigate this hypothesis with the he ... | 2011 | 21829627 |
| effects of predictable and unpredictable food restriction on the stress response in molting and non-molting european starlings (sturnus vulgaris). | this study tested whether an ethologically relevant stressor, a three-week period of food restriction where food was unavailable for four hours a day, caused chronic stress in molting and non-molting captive european starlings. although all birds increased weight during the food restriction period, only non-molting birds increased food intake. morning baseline heart rates increased during the food restriction period and all birds showed a decrease in heart rate when food was absent from the cage ... | 2011 | 21801846 |
| effects of melatonin on peripheral reproductive function: regulation of testicular gnih and testosterone. | study of seasonal reproduction has focused on the brain. here, we show that the inhibition of sex steroid secretion can be seasonally mediated at the level of the gonad. we investigate the direct effects of melatonin on sex steroid secretion and gonadal neuropeptide expression in european starlings (sturnus vulgaris). pcr reveals starling gonads express mrna for gonadotropin inhibitory hormone (gnih) and its receptor (gnihr) and melatonin receptors 1b (mel 1b) and 1c (mel 1c). we demonstrate tha ... | 2011 | 21771888 |
| effects of sibling competition on growth, oxidative stress, and humoral immunity: a two-year brood-size manipulation. | we investigated the effects of ecological context (by comparing data from two consecutive years) and experimentally manipulated nestling developmental conditions (large vs. small brood size) on immune function (immunoglobulin y [igy]) and oxidative stress in nestling european starlings sturnus vulgaris. on the basis of annual differences in chicks' morphological traits and body masses close to fledging, we established that 2007 was a relative low-quality year and 2008 was a relatively high-quali ... | 2011 | 21743256 |
| behavioral and physiological responses of wild-caught european starlings (sturnus vulgaris) to a minor, rapid change in ambient temperature. | free-ranging animals continuously adjust to changes in their environment. the stress response, typified by increases in heart rate and glucocorticoids, is an important physiological response regulating these changes. this study investigated heart rate, corticosterone and behavioral responses of european starlings (sturnus vulgaris) to a rapid 30min decrease in temperature using an air-conditioning unit. ten wild-caught birds were divided into pairs and exposed to four different trials. three tri ... | 2011 | 21723407 |
| dhea and estradiol levels in brain, gonads, adrenal glands, and plasma of developing male and female european starlings. | traditionally, sexual differentiation of the brain was thought to be driven by gonadal hormones, particularly testosterone (t). however, recent studies in songbirds suggest that other steroids may also be important. for example, dehydroepiandrosterone (dhea) can be synthesized by the gonads, adrenal glands, and/or brain and locally metabolized into t and 17β-estradiol (e(2)). here, we examined dhea and e(2) levels in the brain, peripheral tissues, and plasma of wild european starlings (sturnus v ... | 2011 | 21691747 |
| manipulating developmental stress reveals sex-specific effects of egg size on offspring phenotype. | the general lack of experimental evidence for strong, positive effects of egg size on offspring phenotype has led to suggestions that avian egg size is a neutral trait. to better understand the functional significance of intra-specific variation in egg size as a determinant of offspring fitness within a life-history (sex-specific life-history strategies) and an environmental (poor rearing conditions) context, we experimentally increased developmental stress (via maternal feather-clipping) in the ... | 2011 | 21569153 |
| fear and exploration in european starlings (sturnus vulgaris): a comparison of hand-reared and wild-caught birds. | the revision of eu legislation will ban the use of wild-caught animals in scientific procedures. this change is partially predicated on the assumption that captive-rearing produces animals with reduced fearfulness. previously, we have shown that hand-reared starlings (sturnus vulgaris) indeed exhibit reduced fear of humans compared to wild-caught conspecifics. here, we asked whether this reduction in fear in hand-reared birds is limited to fear of humans or extends more generally to fear of nove ... | 2011 | 21526000 |
| mitochondrial dna offers unique insights into invasion history of the common starling. | mitochondrial dna (mtdna) can be a powerful genetic marker for tracing origins and history of invasive populations. here, we use mtdna to address questions relevant to the understanding of invasion pathways of common starlings (sturnus vulgaris) into western australia (wa) and discuss the utility of this marker to provide information useful to invasive species management. mitochondrial sequence data indicate two geographically restricted genetic groups within australia. evidence of dispersal fro ... | 2011 | 21507095 |
| social and breeding status are associated with the expression of gnih. | discoveries of how social behavior can influence the plasticity of gonadotropin-releasing hormone (gnrh) have revolutionized the field of behavioral neuroendocrinology by providing new insights into the neural mechanisms controlling behavior. in 2000, the neuropeptide gonadotropin inhibitory hormone (gnih) was discovered and is changing the way we view how the brain mediates reproduction and associated behaviors. gnih acts as a reproductive 'pause button', momentarily inhibiting the activity of ... | 2011 | 21466656 |
| seasonal and individual variation in singing behavior correlates with α2-noradrenergic receptor density in brain regions implicated in song, sexual, and social behavior. | in seasonally breeding male songbirds, both the function of song and the stimuli that elicit singing behavior change seasonally. the catecholamine norepinephrine (ne) modulates attention and arousal across behavioral states, yet the role of ne in seasonally-appropriate vocal communication has not been well-studied. the present study explored the possibility that seasonal changes in alpha 2-noradrenergic receptors (α(2)-r) within song control regions and brain regions implicated in sexual arousal ... | 2011 | 21397668 |
| carotenoid supplementation positively affects the expression of a non-visual sexual signal. | carotenoids are a class of pigments which are widely used by animals for the expression of yellow-to-red colour signals, such as bill or plumage colour. since they also have been shown to promote immunocompetence and to function as antioxidants, many studies have investigated a potential allocation trade-off with respect to carotenoid-based signals within the context of sexual selection. although an effect of carotenoids on non-visual (e.g. acoustic) signals involved in sexual selection has been ... | 2011 | 21283591 |
| mu-opioid receptor densities are depleted in regions implicated in agonistic and sexual behavior in male european starlings (sturnus vulgaris) defending nest sites and courting females. | social status and resource availability can strongly influence individual behavioral responses to conspecifics. in european starlings, males that acquire nest sites sing in response to females and dominate other males. males without nest sites sing, but not to females, and they do not interact agonistically with other males. little is known about the neural regulation of status- or resource-appropriate behavioral responses to conspecifics. opioid neuropeptides are implicated in birdsong and agon ... | 2011 | 21147175 |
| endocrine disrupting, haematological and biochemical effects of polybrominated diphenyl ethers in a terrestrial songbird, the european starling (sturnus vulgaris). | we exposed female european starlings (sturnus vulgaris) during a 6month period to environmentally relevant concentrations of a pentabromodiphenyl ether (penta-bde) mixture (about 1740μg/kg body weight) through subcutaneous implants, and examined endocrine disruptive, haematological and biochemical effects. to investigate endocrine disrupting effects of pbdes, testosterone, estradiol and thyroid hormones (t(3) and t(4)) were measured in the plasma. we found no significant differences between the ... | 2010 | 20888617 |
| embryonic modulation of maternal steroids in european starlings (sturnus vulgaris). | in birds, maternally derived yolk steroids are a proposed mechanism by which females can adjust individual offspring phenotype to prevailing conditions. however, when interests of mother and offspring differ, parent-offspring conflict will arise and embryonic interests, not those of the mother, should drive offspring response to maternal steroids in eggs. because of this potential conflict, we investigated the ability of developing bird embryos to process maternally derived yolk steroids. we exa ... | 2011 | 20667883 |
| selective behavioral responses to male song are affected by the dopamine agonist gbr-12909 in female european starlings (sturnus vulgaris). | female songbirds use attributes of male song to select mates. different types of male song differ in incentive value (or the ability to attract females). dopamine plays a role in incentive value and reward; however, little is known about its role in selective female behavioral responses to male courtship signals. we examined the effects of the indirect dopamine agonist (dopamine reuptake inhibitor) gbr-12909 on female songbird responses to male song stimuli. female european starlings were played ... | 2010 | 20633541 |
| acute stress induces a rapid increase of testosterone in a songbird: implications for plasma testosterone sampling. | testosterone (t) and glucocorticoids, such as corticosterone, have both been shown to be important for the way vertebrates in general, and birds specifically, react to their immediate environment. for both corticosterone and t, many sources of variation in plasma levels have been demonstrated. interestingly, a small number of studies on bird species have indicated that acute stress can have a positive effect on plasma t levels, analogous to what has been observed for plasma corticosterone levels ... | 2010 | 20603123 |
| neural adaptation to tone sequences in the songbird forebrain: patterns, determinants, and relation to the build-up of auditory streaming. | neural responses to tones in the mammalian primary auditory cortex (a1) exhibit adaptation over the course of several seconds. important questions remain about the taxonomic distribution of multi-second adaptation and its possible roles in hearing. it has been hypothesized that neural adaptation could explain the gradual "build-up" of auditory stream segregation. we investigated the influence of several stimulus-related factors on neural adaptation in the avian homologue of mammalian a1 (field l ... | 2010 | 20563587 |
| stereotyping starlings are more 'pessimistic'. | negative affect in humans and animals is known to cause individuals to interpret ambiguous stimuli pessimistically, a phenomenon termed 'cognitive bias'. here, we used captive european starlings (sturnus vulgaris) to test the hypothesis that a reduction in environmental conditions, from enriched to non-enriched cages, would engender negative affect, and hence 'pessimistic' biases. we also explored whether individual differences in stereotypic behaviour (repetitive somersaulting) predicted 'pessi ... | 2010 | 20464439 |
| fibre architecture and song activation rates of syringeal muscles are not lateralized in the european starling. | the songbird vocal organ, the syrinx, is composed of two sound generators, which are independently controlled by sets of two extrinsic and four intrinsic muscles. these muscles rank among the fastest vertebrate muscles, but the molecular and morphological foundations of this rapid physiological performance are unknown. here we show that the four intrinsic muscles in the syrinx of male european starlings (sturnus vulgaris) are composed of fast oxidative and superfast fibres. dorsal and ventral tr ... | 2010 | 20228343 |
| seasonal changes in concentrations of plasma lh and prolactin associated with the advance in the development of photorefractoriness and molt by high temperature in the starling. | in a study on starlings (sturnus vulgaris) kept on a simulated annual cycle in photoperiod, temperature had no effect on the timing or rate of testicular maturation but high temperature resulted in an advance in the timing of testicular regression and molt (dawson, 2005). this study asks whether the earlier gonadal regression in response to higher temperature represents a central neuroendocrine response to temperature, and secondly, whether prolactin plays a role in the earlier regression. castr ... | 2010 | 20152838 |
| birds learn to use distastefulness as a signal of toxicity. | aposematic prey advertise their toxicity using conspicuous visual signals that predators quickly learn to avoid. however, it is advantageous for predators not to simply avoid toxic prey, but to learn about the amount of toxin that prey contain, and include them in their diets when the nutritional gains are high relative to the costs of ingesting the toxin. therefore, when foraging on a defended prey population where individuals vary in their toxin concentration, predators should learn to use cue ... | 2010 | 20129989 |
| chronic psychological stress alters body weight and blood chemistry in european starlings (sturnus vulgaris). | one hallmark of chronic stress is a decrease in body weight that rebounds once chronic stress is alleviated. we applied chronic psychological stress by exposing european starlings (sturnus vulgaris) to a previously validated chronic stress protocol (csp) consisting of 4 different randomly applied stressors per day. experimental design consisted of a 21 day csp (csp1), a 60day recovery (r1), a second 14 day csp (csp2), and a second 30 day recovery (r2). body weight decreased by approximately 5% d ... | 2010 | 20096363 |
| sleep-dependent consolidation of auditory discrimination learning in adult starlings. | memory consolidation is widely believed to benefit from sleep. sleep-dependent memory consolidation has been established broadly in humans, appearing in declarative and procedural tasks. animal studies have indicated a variety of mechanisms that could potentially serve as the neural basis of sleep-dependent consolidation, such as the offline replay of waking neural activity and the modulation of specific sleep parameters or synaptic strength during sleep. memory consolidation, however, cannot be ... | 2010 | 20071524 |
| representations of conspecific song by starling secondary forebrain auditory neurons: toward a hierarchical framework. | the functional organization giving rise to stimulus selectivity in higher-order auditory neurons remains under active study. we explored the selectivity for motifs, spectrotemporally distinct perceptual units in starling song, recording the responses of 96 caudomedial mesopallium (cmm) neurons in european starlings (sturnus vulgaris) under awake-restrained and urethane-anesthetized conditions. a subset of neurons was highly selective between motifs. selectivity was correlated with low spontaneou ... | 2010 | 20032245 |
| choice in multi-alternative environments: a trial-by-trial implementation of the sequential choice model. | the sequential choice model (scm) proposes that latencies to accept options presented alone can be used to predict preferences between these options when they are presented simultaneously. scm has been proposed and tested in experiments where only two alternatives were present. to further challenge the model, we trained and tested european starlings (sturnus vulgaris) in an environment with a background of four alternatives differing in delay to reinforcement. unexpected binary choices between t ... | 2010 | 19948210 |
| plasticity in singing effort and its relationship with monoamine metabolism in the songbird telencephalon. | factors intrinsic or extrinsic to individuals, such as their quality or the quality of competition in their social environment, can influence their communication signaling effort. we hypothesized that telencephalic monoamine secretion mediates the effects of a male's own quality and quality of his social environment on his sexual signaling effort. the duration of a male european starling's (sturnus vulgaris) principal sexual signal, his song, positively correlates with several aspects of his qua ... | 2010 | 19899137 |
| will the early bird get the mate? egg lay order influences neural development in european starling chicks. | we investigated the role of egg lay order on growth and neural development in pre-fledgling european starlings, sturnus vulgaris. chicks hatched from early-laid eggs had larger relative ra volumes than chicks hatched from later-laid eggs. there were no relationships between lay order and the volume of other brain regions, or chick growth metrics. in adult birds, ra volume is related to song repertoire size, and may affect mate attraction ability. lay order effects on adult song nuclei should be ... | 2010 | 19883698 |
| structural changes between seasons in the songbird auditory forebrain. | the song control system (scs) of seasonal songbirds shows remarkable seasonal plasticity. male starlings (sturnus vulgaris) sing throughout the year, but in the breeding season, when concentrations of testosterone are elevated, the song is highly sexually motivated. the main goal of this study was to investigate structural seasonal changes in regions involved in auditory processing and in socio-sexual behavior. using in vivo diffusion tensor imaging (dti), we measured in breeding and nonbreeding ... | 2009 | 19864568 |
| variation in plasma leptin-like immunoreactivity in free-living european starlings (sturnus vulgaris). | leptin, a protein hormone secreted by fat cells, is best known for its role as an adiposity signal; however, leptin has diverse physiological roles ranging from regulation of feeding behavior and body weight, to effects on reproduction and immune function. although leptin has been extensively studied in mammals, the identification and function of leptin in birds remains controversial, and studies have focused on captive or domesticated species. here, we describe changes in plasma leptin-like imm ... | 2010 | 19796643 |
| combined effects of molt and chronic stress on heart rate, heart rate variability, and glucocorticoid physiology in european starlings. | molt is an important life-history stage in avian species, but little is known about the effects of chronic stress during this period. three weeks after the onset of molt, captive european starlings (sturnus vulgaris) were exposed to 18 days of chronic stress, induced with four 30-minute randomized stressors presented daily. birds showed no chronic-stress-induced changes in heart rate or heart rate variability when measured either during the middle of the day or at night. these data suggest that ... | 2009 | 19699812 |
| chronic stress alters glucocorticoid receptor and mineralocorticoid receptor mrna expression in the european starling (sturnus vulgaris) brain. | although the glucocorticoid response to acute short-term stress is an adaptive physiological mechanism that aids in the response to and survival of noxious stimuli, chronic stress is associated with a negative impact on health. in wild-caught european starlings (sturnus vulgaris), chronic stress alters the responsiveness of hypothalamic-pituitary-adrenal (hpa) axis as measured by the acute corticosterone response. in the present study, we investigated potential underlying neuroendocrine mechanis ... | 2009 | 19686439 |
| wild european starlings (sturnus vulgaris) adjust to captivity with sustained sympathetic nervous system drive and a reduced fight-or-flight response. | although research on wild species typically involves capture, handling, and some degree of captivity, few studies examine how these actions affect and/or alter the animal's underlying stress physiology. furthermore, we poorly understand the immediate changes that occur as wild animals adjust to captive conditions. most studies to date have investigated relatively long-term changes in the glucocorticoid response to an acute stressor, but immediate changes in the fight-or-flight response are relat ... | 2014 | 19642947 |
| quantification of abnormal repetitive behaviour in captive european starlings (sturnus vulgaris). | stereotypies are repetitive, unvarying and goalless behaviour patterns that are often considered indicative of poor welfare in captive animals. quantifying stereotypies can be difficult, particularly during the early stages of their development when behaviour is still flexible. we compared two methods for objectively quantifying the development of route-tracing stereotypies in caged starlings. we used markov chains and t-pattern analysis (implemented by the software package, theme) to identify p ... | 2009 | 19622388 |
| song competition changes the brain and behavior of a male songbird. | males should adjust their behavior and its neural substrates according to the quality of competition that they assess by eavesdropping on other males' courtship signals. in european starlings (sturnus vulgaris), females base mate choice, in part, on aspects of male song associated with its length, which positively correlates with the males' reproductive success, immunocompetence, age and ability to repel competing males. to determine how variation in the quality of male courtship song affects th ... | 2009 | 19617434 |
| photoperiodic condition is associated with region-specific expression of gnrh1 mrna in the preoptic area of the male starling (sturnus vulgaris). | many seasonally breeding avian species exhibit marked changes in hypothalamic content of gonadotropin-releasing vhormone 1 (gnrh1) protein that are reflective of breeding condition. we recently cloned the gnrh1 cdna in european starlings and demonstrated that changes in gnrh1 mrna levels occur with a time course similar to what has been observed with gnrh1 protein. however, we did not previously resolve whether these differences were attributable to changes in the number of cells expressing the ... | 2009 | 19516022 |
| adult: young ratio influences song acquisition in female european starlings (sturnus vulgaris). | one parallel between humans and most songbirds is the fact that young require social interactions with an adult to acquire specific vocalizations. songbirds are considered good models for comparative studies, although reports to date concern almost exclusively male songbirds. in addition, adult influence on vocal communication is generally investigated only in restricted social contexts (usually dyads). here, the authors analyzed song learning and spatial associations among young female starling ... | 2009 | 19450026 |
| d1-like dopamine receptor density in nuclei involved in social behavior correlates with song in a context-dependent fashion in male european starlings. | research in songbirds shows that singing behavior is regulated by both brain areas involved in vocal behavior as well as those involved in social behavior. interestingly, the precise role of these regions in song can vary as a function of the social, environmental and breeding context. to date, little is known about the neurotransmitters underlying such context-dependent regulation of song. dopamine (da) modulates highly motivated, goal-directed behaviors (including sexually motivated song) and ... | 2009 | 19356680 |
| invasive species can't cover their tracks: using microsatellites to assist management of starling (sturnus vulgaris) populations in western australia. | invasive species are known to cause environmental and economic damage, requiring management by control agencies worldwide. these species often become well established in new environments long before their detection, resulting in a lack of knowledge regarding their history and dynamics. when new invasions are discovered, information regarding the source and pathway of the invasion, and the degree of connectivity with other populations can greatly benefit management strategies. here we use invasiv ... | 2009 | 19317845 |
| lesions to the medial preoptic nucleus affect immediate early gene immunolabeling in brain regions involved in song control and social behavior in male european starlings. | the medial preoptic nucleus (pom) is a brain region outside of the song control system of songbirds. it has been implicated in song production, sexual motivation, and the integration of both sensory and hormonal information with appropriate behavioral responses. the pom is well positioned neuroanatomically to interact with multiple regions involved in song, social behavior, and motivation. however, little is known about the brain regions with which the pom directly or indirectly communicates to ... | 2009 | 19245371 |
| independent effects of song quality and experience with photostimulation on expression of the immediate, early gene zenk (egr-1) in the auditory telencephalon of female european starlings. | age influences behavioral decisions such as reproductive timing and effort. in photoperiodic species, such age effects may be mediated, in part, by the individual's age-accrued experience with photostimulation. in female european starlings (sturnus vulgaris) that do not differ in age, experimental manipulation of photostimulation experience (photoexperience) affects hypothalamic, pituitary, and gonadal activity associated with reproductive development. does photoexperience also affect activity i ... | 2009 | 19224564 |
| heart rate and heart-rate variability responses to acute and chronic stress in a wild-caught passerine bird. | the cardiovascular-stress response has been studied extensively in laboratory animals but has been poorly studied in naturally selected species. we determined the relative roles of the sympathetic nervous system (sns) and the parasympathetic nervous system (pns) in regulating stress-induced changes in heart rate (hr) in wild-caught european starlings (sturnus vulgaris). in both heart-rate variability (hrv) analysis and receptor blockade (atropine and propranolol) experiments, baseline hr was con ... | 2013 | 19115847 |
| seasonal rewiring of the songbird brain: an in vivo mri study. | the song control system (scs) of songbirds displays a remarkable plasticity in species where song output changes seasonally. the mechanisms underlying this plasticity are barely understood and research has primarily been focused on the song nuclei themselves, largely neglecting their interconnections and connections with other brain regions. we investigated seasonal changes in the entire brain, including the song nuclei and their connections, of nine male starlings (sturnus vulgaris). at two tim ... | 2008 | 19032586 |
| an exposure study with polybrominated diphenyl ethers (pbdes) in female european starlings (sturnus vulgaris): toxicokinetics and reproductive effects. | we exposed female european starlings to a pentabromodiphenyl ether (penta-bde) mixture through subcutaneous implants, and examined levels and profiles of polybrominated diphenyl ethers (pbdes) together with reproductive effects. sum pbde levels increased significantly in the serum of the exposed females from 218+/-43 to 23,400+/-2035 pg/ml. sum pbde concentrations in the eggs of the exposed group ranged from 130+/-12 to 220+/-37 ng/g wet weight (ww). the profile in serum after egg laying was ver ... | 2009 | 18977567 |
| elevated yolk androgen levels and the expression of multiple sexually selected male characters. | maternal hormones in bird eggs modulate not only offspring development, but recently it has also been shown that these effects can persist into adult life. a number of long-lasting effects concern traits of which the expression or development is modulated by androgens. this suggests that the nature of yolk hormone-mediated maternal effects may be organizational. maternal androgens may therefore play an important role in sexual selection, since the expression of sexually selected male characters ... | 2009 | 18976657 |
| juveniles exposed to embryonic corticosterone have enhanced flight performance. | exposure to maternally derived glucocorticoids during embryonic development impacts offspring phenotype. although many of these effects appear to be transiently 'negative', embryonic exposure to maternally derived stress hormones is hypothesized to induce preparative responses that increase survival prospects for offspring in low-quality environments; however, little is known about how maternal stress influences longer-term survival-related performance traits in free-living individuals. using an ... | 2009 | 18842541 |
| optimal foraging and beyond: how starlings cope with changes in food availability. | foraging adaptations include behavioral and physiological responses, but most optimal foraging models deal exclusively with behavioral decision variables, taking other dimensions as constraints. to overcome this limitation, we measured behavioral and physiological responses of european starlings sturnus vulgaris to changes in food availability in a laboratory environment. the birds lived in a closed economy with a choice of two foraging modes (flying and walking) and were observed under two trea ... | 1998 | 18811363 |
| the adaptive value of stress-induced phenotypes: effects of maternally derived corticosterone on sex-biased investment, cost of reproduction, and maternal fitness. | the question of why maternal stress influences offspring phenotype is of significant interest to evolutionary physiologists. although embryonic exposure to maternally derived glucocorticoids (i.e., corticosterone) generally reduces offspring quality, effects may adaptively match maternal quality with offspring demand. we present results from an interannual field experiment in european starlings (sturnus vulgaris) designed explicitly to examine the fitness consequences of exposing offspring to ma ... | 2008 | 18793091 |
| a behavioral analysis of prey detection lateralization and unilateral transfer in european starlings (sturnus vulgaris). | it has been suggested that birds prefer to use a particular eye while learning to detect cryptic prey and that this eye preference enhances foraging performance. european starlings (sturnus vulgaris) with the left, right, or both eyes available learned to detect inconspicuous cues associated with the presence of hidden prey. acquisition scores were not significantly different between left and right-eyed birds; however, performance in the binocular condition was significantly higher than in the t ... | 2008 | 18639618 |
| evidence that dopamine within motivation and song control brain regions regulates birdsong context-dependently. | vocal communication is critical for successful social interactions among conspecifics, but little is known about how the brain regulates context-appropriate communication. the neurotransmitter dopamine (da) is involved in modulating highly motivated, goal-directed behaviors (including sexually motivated singing behavior), and emerging data suggest that the role of da in vocal communication may differ depending on the context in which it occurs. to address this possibility, relationships between ... | 2008 | 18619478 |
| new statistical tools for analyzing the structure of animal groups. | the statistical characterization of the spatial structure of large animal groups has been very limited so far, mainly due to a lack of empirical data, especially in three dimensions (3d). here we focus on the case of large flocks of starlings (sturnus vulgaris) in the field. we reconstruct the 3d positions of individual birds within flocks of up to few thousands of elements. in this respect our data constitute a unique set. we perform a statistical analysis of flocks' structure by using two quan ... | 2009 | 18586280 |
| fecal glucocorticoid metabolites of experimentally stressed captive and free-living starlings: implications for conservation research. | fecal glucocorticoid metabolite (fgm) analysis has received considerable attention in conservation biology because it has potential to be used as a noninvasive measure of stress in animals. there has been a recent and extensive literature describing the importance of technical, physiological, and biological validations of this technique, yet surprisingly little is known about how fgm concentrations change during chronic stress. therefore, we experimentally induced chronic stress in both captive ... | 2008 | 18554600 |
| increased energy expenditure but decreased stress responsiveness during molt. | baseline and stress-induced corticosterone (cort), heart rate (fh), and energy expenditure were measured in eight captive european starlings sturnus vulgaris during and following a prebasic molt. the fh and oxygen consumption (v o2 ) were measured simultaneously across a range of heart rates, and energy expenditure (kj/d) was then calculated from data. energy expenditure and fh were strongly and positively correlated in each individual. baseline fh and energy expenditure were significantly highe ... | 2013 | 18537472 |
| behavioural and hormonal effects of social isolation and neophobia in a gregarious bird species, the european starling (sturnus vulgaris). | separating gregarious individuals from their group members often results in behavioural and physiological changes, like increased levels of corticosterone. testosterone and corticosterone, in particular, have been implicated in the response of mammals to novelty. data in birds are, however, rare. the presence or absence of group members may also influence an individual's response to novel stimuli. we assessed the behaviour and hormonal response of european starlings (sturnus vulgaris) to a novel ... | 2008 | 18514197 |
| use and husbandry of captive european starlings (sturnus vulgaris) in scientific research: a review of current practice. | we reviewed the use of captive european starlings (sturnus vulgaris) in scientific research published between 2000 and 2004. we estimated the numbers of birds used and documented their origin and the range of husbandry regimes employed with the aim of comparing current practice with the new european guidelines for husbandry of laboratory animals. over the five-year period, 106 primary articles report the use of an estimated total of 2490 captive starlings. the majority of birds were caught from ... | 2008 | 18435870 |
| sex differences in dhea and estradiol during development in a wild songbird: jugular versus brachial plasma. | sexual differentiation of the brain has traditionally been thought to be driven by gonadal hormones, particularly testosterone (t). recent studies in songbirds and other species have indicated that non-gonadal sex steroids may also be important. for example, dehydroepiandrosterone (dhea)--a sex steroid precursor that can be synthesized in the adrenal glands and/or brain--can be converted into active sex steroids, such as 17beta-estradiol (e(2)), within the brain. here, we examine plasma dhea and ... | 2008 | 18423637 |
| pollutants increase song complexity and the volume of the brain area hvc in a songbird. | environmental pollutants which alter endocrine function are now known to decrease vertebrate reproductive success. there is considerable evidence for endocrine disruption from aquatic ecosystems, but knowledge is lacking with regard to the interface between terrestrial and aquatic ecosystems. here, we show for the first time that birds foraging on invertebrates contaminated with environmental pollutants, show marked changes in both brain and behaviour. we found that male european starlings (stur ... | 2008 | 18301751 |
| auditory memory for temporal characteristics of sound. | this study evaluates auditory memory for variations in the rate of sinusoidal amplitude modulation (sam) of noise bursts in the european starling (sturnus vulgaris). to estimate the extent of the starling's auditory short-term memory store, a delayed non-matching-to-sample paradigm was applied. the birds were trained to discriminate between a series of identical "sample stimuli" and a single "test stimulus". the birds classified sam rates of sample and test stimuli as being either the same or di ... | 2008 | 18299849 |
| the integration of song environment by catecholaminergic systems innervating the auditory telencephalon of adult female european starlings. | mate choice is among the most consequential decisions a sexually reproducing organism can make. in many songbird species, females make mate-choice decisions based, in part, on variation between males in songs that reflect their quality. importantly, females may adjust their choice relative to the prevalence of high quality songs. in european starlings (sturnus vulgaris), females prefer males that primarily sing long songs over those that primarily sing short songs, and sensitivity of the auditor ... | 2008 | 18278799 |
| simultaneous and sequential choice as a function of reward delay and magnitude: normative, descriptive and process-based models tested in the european starling (sturnus vulgaris). | the authors analyze prevalent theoretical and empirical quantitative models of choice using data from european starlings (sturnus vulgaris). the different models originate from diverse lines of thinking, including optimal foraging theory, descriptive behavioral analysis, and temporal discounting. the authors also investigate the sequential choice model (scm) that predicts choice between simultaneous alternatives as a function of behavior in sequential encounters. scm assumes that simultaneous en ... | 2008 | 18248116 |
| the effects of chronic psychological and physical stress on feather replacement in european starlings (sturnus vulgaris). | corticosterone (cort) is seasonally modulated in many passerines, with plasma cort concentrations lowest during the prebasic molt, when all feathers are replaced. recent evidence indicating that cort implants slow the rate of feather regrowth in molting birds suggests that plasma cort concentrations are downregulated during molt in order to avoid the inhibition of feather growth caused by the protein catabolic activity of cort. to further test this hypothesis, we examined whether endogenous cort ... | 2008 | 18032078 |
| gonadotropin-inhibitory hormone neurons interact directly with gonadotropin-releasing hormone-i and -ii neurons in european starling brain. | gonadotropin-inhibitory hormone (gnih) is a hypothalamic dodecapeptide (sikpsaylplrf-nh(2)) that directly inhibits gonadotropin synthesis and release from quail pituitary. the action of gnih is mediated by a novel g-protein coupled receptor. this gonadotropin-inhibitory system may be widespread in vertebrates, at least birds and mammals. in these higher vertebrates, histological evidence suggests contact of gnih immunoreactive axon terminals with gnrh neurons, thus indicating direct regulation o ... | 2008 | 17901228 |
| detecting modulated signals in modulated noise: (ii) neural thresholds in the songbird forebrain. | sounds in the real world fluctuate in amplitude. the vertebrate auditory system exploits patterns of amplitude fluctuations to improve signal detection in noise. one experimental paradigm demonstrating these general effects has been used in psychophysical studies of 'comodulation detection difference' (cdd). the cdd effect refers to the fact that thresholds for detecting a modulated, narrowband noise signal are lower when the envelopes of flanking bands of modulated noise are comodulated with ea ... | 2007 | 17897401 |
| auditory short-term memory persistence for tonal signals in a songbird. | this paper presents an animal model for studying the persistence of auditory memory for tonal signals. five european starlings (sturnus vulgaris) were trained in a go/nogo delayed nonmatching-to-sample task to discriminate between a series of identical "sample stimuli" and a single "test stimulus." frequencies of sample and test stimuli should be classified as being either the same or different. the performance of the birds is measured as the percentage of correct classifications. three paramete ... | 2007 | 17550183 |
| a comprehensive molecular phylogeny of the starlings (aves: sturnidae) and mockingbirds (aves: mimidae): congruent mtdna and nuclear trees for a cosmopolitan avian radiation. | we generated a comprehensive phylogeny for the avian families sturnidae (starlings, mynas, rhabdornis, oxpeckers, and allies) and mimidae (mockingbirds, thrashers, and allies) to explore patterns of morphological and behavioral diversification. reconstructions were based on mitochondrial dna sequences from five coding genes (4108 bp), and nuclear intron sequences from four loci (2974 bp), for most taxa, supplemented with ndii gene sequences (1041 bp) derived from museum skin specimens from addit ... | 2007 | 17502157 |