| suttonella ornithocola sp. nov., from birds of the tit families, and emended description of the genus suttonella. | phenotypic and phylogenetic studies were performed on three strains of gram-negative, rod-shaped organisms recovered from dead birds of the tit families (blue tit, coal tit and long-tailed tit). morphological, cultural and biochemical studies indicated that the organisms were related to the family cardiobacteriaceae in the gamma-subclass of the proteobacteria. comparative 16s rrna gene sequencing studies confirmed these findings and demonstrated that the bacterium represents a hitherto unknown s ... | 2005 | 16280481 |
| acute necrotising pneumonitis associated with suttonella ornithocola infection in tits (paridae). | suttonella ornithocola, first isolated from the lungs of british tit species in 1996, was found to be a novel bacterium belonging to the family cardiobacteriaceae. comprehensive surveillance of garden bird mortality across great britain between april 2005 and april 2009 involved post mortem and microbiological examination of 82 tits (paridae; multiple species) and six long-tailed tits (aegithalidae; aegithalos caudatus). s. ornithocola was isolated from six birds submitted from six incidents of ... | 2011 | 20427213 |
| past hybridization between two east asian long-tailed tits (aegithalos bonvaloti and a. fuliginosus). | incomplete lineage sorting and hybridization are two major nonexclusive causes of haplotype sharing between species. distinguishing between these two processes is notoriously difficult as they can generate similar genetic signatures. previous studies revealed that the mitochondrial dna (mtdna) differentiation between two east asian long-tailed tits (aegithalos bonvaloti and a. fuliginosus) was extremely low, even lower than intraspecific differentiation in some other long-tailed tits. using a co ... | 2014 | 24883074 |
| new distribution of picobia caudati skoracki and hebda, 2004 (acariformes: syringophilidae): an ectoparasite of long-tailed tit aegithalos caudatus (l.) (passeriformes: aegithalidae) | quill mite species picobia caudati skoracki and hebda, 2004 collected from its type host aegithalos caudatus (l.) is recorded from seven new localities in europe (france, germany, italy, macedonia) and asia (china, russia, japan). | 2016 | 28170211 |
| diurnal brooding behavior of long-tailed tits (aegithalos caudatus glaucogularis). | brooding is a major breeding investment of parental birds during the early nestling stage, and has important effects on the development and survival of nestlings. investigating brooding behavior can help to understand avian breeding investment strategies. from january to june in 2013 and 2014, we studied the brooding behaviors of long-tailed tits (aegithalos caudatus glaucogularis) in dongzhai national nature reserve, henan province, china. we analyzed the relationships between parental diurnal ... | 2016 | 27029865 |
| social genetic and social environment effects on parental and helper care in a cooperatively breeding bird. | phenotypes expressed in a social context are not only a function of the individual, but can also be shaped by the phenotypes of social partners. these social effects may play a major role in the evolution of cooperative breeding if social partners differ in the quality of care they provide and if individual carers adjust their effort in relation to that of other carers. when applying social effects models to wild study systems, it is also important to explore sources of individual plasticity tha ... | 2015 | 26063846 |
| helping in cooperatively breeding long-tailed tits: a test of hamilton's rule. | inclusive fitness theory provides the conceptual framework for our current understanding of social evolution, and empirical studies suggest that kin selection is a critical process in the evolution of animal sociality. a key prediction of inclusive fitness theory is that altruistic behaviour evolves when the costs incurred by an altruist (c) are outweighed by the benefit to the recipient (b), weighted by the relatedness of altruist to recipient (r), i.e. hamilton's rule rb > c. despite its centr ... | 2014 | 24686941 |
| phenological indices of avian reproduction: cryptic shifts and prediction across large spatial and temporal scales. | climate change-induced shifts in phenology have important demographic consequences, and are frequently used to assess species' sensitivity to climate change. therefore, developing accurate phenological predictions is an important step in modeling species' responses to climate change. the ability of such phenological models to predict effects at larger spatial and temporal scales has rarely been assessed. it is also not clear whether the most frequently used phenological index, namely the average ... | 2013 | 23919135 |
| ecological and demographic correlates of helping behaviour in a cooperatively breeding bird. | the evolution of cooperation is a persistent problem for evolutionary biologists. in particular, understanding of the factors that promote the expression of helping behaviour in cooperatively breeding species remains weak, presumably because of the diverse nature of ecological and demographic drivers that promote sociality. in this study, we use data from a long-term study of a facultative cooperative breeder, the long-tailed tit aegithalos caudatus, to investigate the factors influencing annual ... | 2013 | 23347411 |
| brood sex ratio variation in a cooperatively breeding bird. | in cooperatively breeding species, the fitness consequences of producing sons or daughters depend upon the fitness impacts of positive (repayment hypothesis) and negative (local competition hypothesis) social interactions among relatives. in this study, we examine brood sex allocation in relation to the predictions of both the repayment and the local competition hypotheses in the cooperatively breeding long-tailed tit aegithalos caudatus. at the population level, we found that annual brood sex r ... | 2011 | 21306463 |
| sexual size dimorphism and sex identification using morphological traits of two aegithalidae species. | the black-throated tit, aegithalos concinnus, and long-tailed tit, a. caudatus, are two widely-distributed species of aegithalidae. they are thought to be monomorphic and thus difficult to differentiate between sexes in the field. we determined the sex of 296 black-throated tits and 129 long-tailed tits using dna analysis, evaluated their sexual size dimorphism, and developed discriminant models to identify sex based on morphometries, including bill length, bill depth, bill-head length, maximum ... | 2010 | 21110721 |
| kinship affects investment by helpers in a cooperatively breeding bird. | helping behaviour in cooperative breeding systems has been attributed to kin selection, but the relative roles of direct and indirect fitness benefits in the evolution of such systems remain a matter of debate. in theory, helpers could maximize the indirect fitness benefits of cooperation by investing more in broods with whom they are more closely related, but there is little evidence for such fine-scale adjustment in helper effort among cooperative vertebrates. in this study, we used the unusua ... | 2010 | 20534616 |
| consequences of 'load-lightening' for future indirect fitness gains by helpers in a cooperatively breeding bird. | 1. helpers that invest energy in provisioning the offspring of related individuals stand to gain indirect fitness benefits from doing so. first, if the helper's effort is additional to that of the parents (additive) the productivity of the current breeding attempt can be increased. secondly, if the parents reduce their workload (compensation) this can result in future indirect fitness gains to the helper via increased breeder survival; termed 'load-lightening'. 2. long-tailed tits (aegithalos ca ... | 2010 | 20132371 |
| phylogeny of long-tailed tits and allies inferred from mitochondrial and nuclear markers (aves: passeriformes, aegithalidae). | in this paper we provide a molecular phylogeny based on three mitochondrial and three nuclear markers for all long-tailed tit species of the genus aegithalos including several doubtful subspecies (17 taxa) plus three close allies of se asian leptopoecile and north american psaltriparus. genus aegithalos is divided into three major clades, two of them showing only minor differentiation. separation of two mitchondrial haploytpe clusters in the n palearctic long-tailed tit, ae. caudatus, was dated ... | 2010 | 20102744 |
| temporal variation in fitness payoffs promotes cooperative breeding in long-tailed tits aegithalos caudatus. | cooperative breeding is paradoxical because some individuals forego independent reproduction and instead help others to reproduce. the ecological constraints model states that such behavior arises because of constraints on independent reproduction. spatial variation in constraints has been shown to co-vary with the incidence of cooperative breeding in correlational and experimental studies. here, we examine whether temporally variable ecological constraints can act in a similar way to promote co ... | 2002 | 18707485 |
| dispersal of sibling coalitions promotes helping among immigrants in a cooperatively breeding bird. | kin selection is a major force in social evolution, but dispersal is often assumed to reduce its impact by diluting kinship. in most cooperatively breeding vertebrates, in which more than two individuals care for young, juveniles delay dispersal and become helpers in family groups. in long-tailed tits (aegithalos caudatus), however, offspring disperse to breed and helpers are failed breeders that preferentially aid kin. helping also occurs among immigrants, but their origins are unknown and coop ... | 2008 | 18522914 |
| learned kin recognition cues in a social bird. | in many cooperatively breeding birds, kin selection has an important role in the evolution and maintenance of social behaviour, and 'helpers' can maximize indirect fitness gains by preferentially allocating care to close relatives. although there is evidence for kin-biased helping behaviour in several species, the mechanism of kin recognition underlying this behaviour is poorly understood. vocalizations are the most commonly used cues in avian recognition systems, but the effectiveness of vocal ... | 2005 | 15858573 |
| heritability of parental effort in a passerine bird. | the study of the evolution of parental care is central to our understanding of social systems, sexual selection, and interindividual conflict, yet we know virtually nothing about the genetic architecture of parental care traits in natural populations. in this paper, we use data from a long term field study of a passerine bird, the long-tailed tit (aegithalos caudatus), to examine the heritability of the rate at which parents feed offspring. this measure of effort is positively related to offspri ... | 2003 | 14575340 |
| dispersal costs set the scene for helping in an atypical avian cooperative breeder. | the ecological constraints hypothesis is suggested to explain the evolution of cooperative breeding in birds. this hypothesis predicts that the scene for cooperative breeding is set when ecological factors constrain offspring from dispersal. this prediction was tested in the atypical cooperative breeding system of the long-tailed tit, aegithalos caudatus, by comparing the degree of philopatry and cooperation in an isolated and a contiguous site whilst experimentally controlling for confounding a ... | 2001 | 12123305 |
| experimental evidence for kin-biased helping in a cooperatively breeding vertebrate. | the widespread belief that kin selection is necessary for the evolution of cooperative breeding in vertebrates has recently been questioned. these doubts have primarily arisen because of the paucity of unequivocal evidence for kin preferences in cooperative behaviour. using the cooperative breeding system of long-tailed tits (aegithalos caudatus) in which kin and non-kin breed within each social unit and helpers are failed breeders, we investigated whether helpers preferentially direct their car ... | 2001 | 11600082 |
| kin discrimination in cooperatively breeding long-tailed tits. | long-tailed tits aegithalos caudatus are cooperative breeders in which helpers exhibit a kin preference in their cooperative behaviour. we investigated the mechanism through which this preference is achieved by first conducting an experiment for testing whether breeders could recognize the calls of their relatives while controlling for spatial effects. we found that there were significant differences in the responses of breeders to the vocalizations of kin and non-kin, suggesting that vocal cues ... | 2001 | 11370960 |
| divorce in cooperatively breeding long-tailed tits: a consequence of inbreeding avoidance? | the decision of whether to divorce a breeding partner between reproductive attempts can significantly affect individual fitness. in this paper, we report that 63% of surviving pairs of long-tailed tits aegithalos caudatus divorced between years. we examine three likely explanations for the high divorce rate in this cooperative breeder. the 'better option' hypothesis predicts that divorce and re-pairing increases an individual's reproductive success. however, divorcees did not secure better partn ... | 2000 | 10819152 |
| influences of population size and woodland area on bird species distributions in small woods. | distributions of individual bird species in 151 small woods (size range 0.02-30 ha) were investigated in 3 consecutive years during which the abundance of certain species varied markedly. relationships between the probabilities of certain bird species breeding and woodland area were described using incidence functions derived from logistic regression analysis. in general, for species which were largely dependent on woodland and seldom occurred in other habitats (such as hedgerows and gardens), t ... | 1996 | 28307128 |
| an experimental test of the information model for negotiation of biparental care. | theoretical modelling of biparental care suggests that it can be a stable strategy if parents partially compensate for changes in behaviour by their partners. in empirical studies, however, parents occasionally match rather than compensate for the actions of their partners. the recently proposed "information model" adds to the earlier theory by factoring in information on brood value and/or need into parental decision-making. this leads to a variety of predicted parental responses following a ch ... | 2011 | 21611180 |
| modified forest rotation lengths: long-term effects on landscape-scale habitat availability for specialized species. | we evaluated the long-term implications from modifying rotation lengths in production forests for four forest-reliant species with different habitat requirements. by combining simulations of forest development with habitat models, and accounting both for stand and landscape scale influences, we projected habitat availability over 150 years in a large swedish landscape, using rotation lengths which are longer (+22% and +50%) and shorter (-22%) compared to current practices. in terms of mean habit ... | 2018 | 29329003 |
| mechanistic home range analysis reveals drivers of space use patterns for a non-territorial passerine. | home ranging is a near-ubiquitous phenomenon in the animal kingdom. understanding the behavioural mechanisms that give rise to observed home range patterns is thus an important general question, and mechanistic home range analysis (mhra) provides the tools to address it. however, such analysis has hitherto been principally restricted to scent-marking territorial animals, so its potential breadth of application has not been tested. here, we apply mhra to a population of long-tailed tits aegithalo ... | 2020 | 32779181 |
| cost, risk, and avoidance of inbreeding in a cooperatively breeding bird. | inbreeding is often avoided in natural populations by passive processes such as sex-biased dispersal. but, in many social animals, opposite-sexed adult relatives are spatially clustered, generating a risk of incest and hence selection for active inbreeding avoidance. here we show that, in long-tailed tits (aegithalos caudatus), a cooperative breeder that risks inbreeding by living alongside opposite-sex relatives, inbreeding carries fitness costs and is avoided by active kin discrimination durin ... | 2020 | 32571952 |
| helping decisions and kin recognition in long-tailed tits: is call similarity used to direct help towards kin? | most cooperative breeders live in discrete family groups, but in a minority, breeding populations comprise extended social networks of conspecifics that vary in relatedness. selection for effective kin recognition may be expected for more related individuals in such kin neighbourhoods to maximize indirect fitness. using a long-term social pedigree, molecular genetics, field observations and acoustic analyses, we examine how vocal similarity affects helping decisions in the long-tailed tit aegith ... | 2020 | 32420850 |
| inclusive fitness consequences of dispersal decisions in a cooperatively breeding bird, the long-tailed tit (aegithalos caudatus). | natal dispersal is a demographic trait with profound evolutionary, ecological, and behavioral consequences. however, our understanding of the adaptive value of dispersal patterns is severely hampered by the difficulty of measuring the relative fitness consequences of alternative dispersal strategies in natural populations. this is especially true in social species, in which natal philopatry allows kin selection to operate, so direct and indirect components of inclusive fitness have to be conside ... | 2018 | 30397131 |
| fine-scale genetic structure and helping decisions in a cooperatively breeding bird. | in animal societies, characteristic demographic and dispersal patterns may lead to genetic structuring of populations, generating the potential for kin selection to operate. however, even in genetically structured populations, social interactions may still require kin discrimination for cooperative behaviour to be directed towards relatives. here, we use molecular genetics and long-term field data to investigate genetic structure in an adult population of long-tailed tits aegithalos caudatus, a ... | 2018 | 29543401 |
| genomic differentiation and patterns of gene flow between two long-tailed tit species (aegithalos). | patterns of heterogeneous genomic differentiation have been well documented between closely related species, with some highly differentiated genomic regions ("genomic differentiation islands") spread throughout the genome. differential levels of gene flow are proposed to account for this pattern, as genomic differentiation islands are suggested to be resistant to gene flow. recent studies have also suggested that genomic differentiation islands could be explained by linked selection acting on ge ... | 2017 | 29055167 |
| investment strategies of breeders in avian cooperative breeding systems. | an individual's optimal investment in young depends partly on the number of individuals caring for the same brood. in cooperative breeders, the investment strategy of parents with helpers is variable. when parents maintain the same effort regardless of helper number, helper care is additive. when parents fully compensate for the care of helpers by decreasing their own effort, total care does not increase. a study of long-tailed tits aegithalos caudatus showed that both parental strategies may oc ... | 1999 | 29578784 |