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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Evolution of female ornamentation in the White-shouldered Fairywren (Malurus alboscapulatus)

January 2018 (has links)
acase@tulane.edu / A comprehensive understanding of sexual dichromatism and sexual selection depends on understanding selective pressures on females, which may differ from those experienced by males. Conventional theory suggests that ornamentation in females evolves as the byproduct of selection pressures on males, and is non-adaptive. My dissertation challenges this assumption through a series of linked studies related to female ornamentation in a species of tropical passerine bird, the White-shouldered Fairywren (Malurus alboscapulatus), of New Guinea. The White-shouldered Fairywren is ideally suited to evaluate the evolution of female ornamentation, because populations are characterized by divergence in female plumage coloration from brown (unornamented) to black-and-white (ornamented), with no variation in males, which are uniformly black- and-white. My thesis research employed field-based observation and experimentation with contemporary genomic, endocrine, and microscopy techniques to identify proximate mechanisms, current adaptive function, and evolutionary history of female ornamentation in this system. / 1 / Erik Enbody
2

Biochemical Genetics of Certain Species of the Blackbird Family Icteridae

Smith, Jackson Kelly 12 1900 (has links)
Starch gel electrophoresis was used to compare 14 proteins encoded by 15 loci for seven species of the family Icteridae. A close genetic relationship among these species was classified into three groups. The Agelaiine group contained Agelaius phoeniceus, Sturnella magna, and S. neglecta. The Quiscaline group contained Euphagus cyanocephalus, Cassidix mexicanus, and Quiscalus quiscula. Molothrus ater, the most divergent, was placed in a separate group. Divergence times for the seven species were compared to the literature. Heterozygosity of the seven populations of the two species of Sturnella were compared to determine factors influencing their divergence. Two factors proposed were heterosis in S. neglecta and possible hybridization between S. neglect and S. magna.
3

Vocalizations in the Grey Butcherbird Cracticus Torquatus with Emphasis on Structure in Male Breeding Song: Implications for the Function and Evolution of Song from a Study of a Southern Hemisphere Species.

Johnson, Gayle, n/a January 2003 (has links)
An undue focus on Temperate Zone oscines (songbirds or passerines) has led to a geographical bias in interpretation of song frmnction and evolution. This bias led initially to relatively simplistic theories of the ftmnction of bird song with vocalizations divided into 'songs' and 'calls'. Songs were complex, learned vocalizations, given by males in the breeding season, thnctioning in territory defence and mate attraction and stimulation. Calls, on the other hand, were simple innate vocalizations serving more immediate needs such as begging for food and raising an alarm. Female song, where it occurred, was considered an aberration. Further studies suggested that complex songs were associated with mate attraction functions while simpler songs were associated with territory defence. However it became apparent that the distinction between songs and calls was not nearly so clear-cut and the supposed connection between complexity and function in song was questioned. Moreover it was realised that female song could not be dismissed as a mere aberration. Another problem was the ftmnction of the dawn chorus, where research had failed to find a consistent, all-encompassing explanation. Since most studies had been done on Northern Hemisphere songbirds, it was becoming clear that the geographical focus needed to be broadened. The life histories of Northern Hemisphere TemperateZone songbirds are very different from those in many other regions. In contrast to the situation in this zone, maintenance of year-round territory, territory defence by both male and female, life-long social monogamy and extensive female vocalization are widespread in tropical, subtropical and Southern Hemisphere regions. Recently it has been suggested that more intensive studies of vocalizations in these regions might help clariQi some of these issues and consequently an endemic Australian passerine was chosen for the current study. The study focused on the vocalizationsof the grey butcherbird Cracticus torquatus Artamidae, which displays the life history features described above. The main study population was located in the Brisbane suburbs of Rainworth and Bardon. Additional data were gathered from other Brisbane suburbs and bushland sites within the city and at Lake Broadwater near Dalby, Queensland. Vocalizations were initially recorded electronically and analysed using Canary sound editing program. Vocalization data were supplemented using an aural recording method, which was independently checked for reliability. Behavioural data including posture during vocalizations and interactions with other birds were also gathered. Initial investigationsrevealed the existence of two main categories of vocalizations - those given by the family group during the day, all year round and those given at dawn by males during the breeding season. For the focal study populations, group vocalizations were studied throughout the year over several years, however the song given at dawn by males during the breeding season proved to be quite complex and three birds from three territories in the main study area were chosen as case studies. Recordings were made of the vocalizations of the three case study birds over three breeding seasons. Starting and fmishing times (with respect to civil twilight) were recorded in order to determine both changes in song bout duration and starting time throughout the breeding season. Additional birds from the same area, from the other Brisbane suburbs and from the bushland sites were studied to check the validity of conclusions drawn from the case studies. The results of the investigations revealed a vocalization structure that contrasted strongly with the simple picture of bird song drawn from study ofNorthernHemisphere Temperate Zone passerines. The vocalizations given during the day, often referred to as the 'song' of this species, were very different from the early dawn song given by the male during the breeding season. This latter appeared to be song sensu stricto according to the paradigms developed for Northern Hemisphere birds. The thytime vocalizations, however, fitted neither the classic definition of 'song' nor the classic definition of 'call'. This relatively long-term study revealed different starting time patterns and periodicity for thy vocalizations and male breeding season song. Day vocalizations commenced at a fairly constant time with respect to civil twilight throughoutthe year but breeding season song started progressively earlier from the beginning through to the middle of the season then progressively later till the end of the season. Relative finishing time of breeding song however remained constant so that the duration of breeding season song gradually increased then decreased paralleling the change in starting times. A consequence of the two distinct classes of vocalizations was that there were essentially two distinct 'dawn choruses'. One, consisting of group vocals, was sung all year round; the other was given by males singing 'breeding season' song. Since there was no reason the expect that a single function would necessarily be ascribed to both choruses, this raised the possibility that some of the confusion surrounding the ftinction and nature of the 'dawn chorus' originated from a failure to recognize the existence of two such choruses. Variation in time and space showed ifirther differences between the two vocalization classes. The breeding song of each male was distinctly different from that of his neighbours and there was a marked change in the repertoire of any individual from one year to the next. In marked contrast, daytime vocalization repertoires of neighbouring groups were virtually indistinguishable and changed little from year to year. These findings, together with information from recent literature, suggested that the two song classes had a different ontogeny, function and possibly evolution. It was proposed that territory declaration was the function of dawn singing by grey butcherbird family groups but that the function most consistent with adult male dawn song was attraction of females for extra-pair copulations. It was suggested that chorusing itself was to some extent an accidental by-product of the advantage to the individual or group of singing at dawn although a recently proposed function, the social dynamics function, could not be ruled out. Further differences from the Northern Hemisphere situation were detected in subsong. First, subsong was given by birds in their first year and also by adult males. The finding of subsong in adult males was not without precedent as it has been documented previously for a small number of passerines, especially those that change repertoire from year to year. Subsong in young (first year) birds, however, was unusual in that birds practised in small groups rather than in the complete isolation usually associated with subsong. Moreover they did not practise adult male song but instead practised group daytime vocalizations. It was suggested that it was important for birds to learn to sing in company for the important task of group territory defence. Further investigation of the literature and observations during the present study revealed similar vocalization classes and behaviours in other members of the Artamidae and other endemic Australasian taxa. These literature investigations also revealed that the possession two song vocalization classes was quite widespread although they tended to be restricted (but not exclusive) to males rather than found in males and females. These findings led to furtherresearch into the significanceofAustraliain the evolution of songbirds, the role of co-operative breeding in Australianpasserines, and finally to an hypothesis for a possible origin of male bird song. It is suggested that male song arose in a social environment where the male and female were in frequent vocal communication. If the tendency to seek extra-pair copulations (EPCs) and female choice had already been incorporated into the suite of passerine behaviours, it would be necessary to avoid the mate during such activities and the male would need to advertise with a signal distinct from group vocalizations. Early dawn, with poor light conditions, could be a favourable time for these activities. Thus it is proposed that the ancestral condition was with all group members singing most vocalisations, the intermediate situation was similar to that in the grey butcherbird and the 'advanced' condition was where female and other group member vocalizations (other than calls) have dropped out and only male song remains.
4

Inkiluose perinčių žvirblinių paukščių veisimosi dėsningumai ir galima klimato kaitos įtaka / Regularities of nest box breeding passerine birds and possible impact of climate change

Šimkevičius, Kastytis 14 January 2009 (has links)
Magistro darbe tiriama miško aplinkos sąlygų ir klimato kaitos įtaka inkiluose perintiems žvirbliniams paukščiams. Darbo objektas – inkiluose perintys žvirbliniai paukščiai. Darbo tikslas – ištirti žvirblinių paukščių veisimosi dėsningumus Kazlų Rūdos miškų masyve ir įvertinti klimato kaitos poveikį. Darbo metodai – sistemingai iškeltų inkilų stebėjimas, loginė literatūros analizė, statistinė duomenų analizė. Darbo rezultatai. Atlikus tyrimus Kazlų Rūdos mokomosios miškų urėdijos Jūrės girininkijos miškuose, įvertintas miško aplinkos veiksnių ir klimato kaitos poveikis didžiosios zylės Parus major L. ir margasparnės musinukės Ficedula hypoleuca Pall. veisimuisi ir gauti tokie rezultatai: didžiosios zylės pirmojo kiaušinio padėjimo laiką tiesiogiai įtakoja vidutinė paros temperatūra, tačiau reakcija yra uždelsta 4 dienomis; didžiosios zylės antrojoje vadoje arčiau miško aikštės, kirtavietės ar jaunuolyno krašto deda didesnes dėtis; šiltėjančio klimato pasėkoje didžiosios zylės pradeda veistis vidutiniškai 5 dienomis anksčiau lyginant su A. Aleknonio pateiktais duomenimis (1958-1982); dėl ankstesnio didžiųjų zylių veisimosi pirmojoje vadoje, taip pat dėl pailgėjusio periodo su aukštesnėmis temperatūromis antra vada pradedama dėti anksčiau ir būna gausesnė. / This study is analyzing Forest environment conditions and changes in climate influence on breeding passerine birds hatched in nest boxes. The Object – Passerine birds breeding in nest boxes. The aim of this paper is to investigate regularities of breeding passerine birds in Kazlų Rūda forest and to estimate possible impact of climate change. Methods – observation of systematically placed nest boxes, logical literature analysis, statistical analysis of data. Results. Study was carried on Training State Forest Enterprise of Kazlų Rūda, Forestry of Jūrė. Impact of forest environment and changes in climate on breeding of Great Tit (Parus major) and Pied Fly Catcher (Ficedula hypoleuca) were estimated. Following results were found: time of first laying egg is directly influenced by mean temperature of the day, but reaction time is delayed for 4 days; in the second broad that are closer to the forest openings, forest cuttings or brush stage forest edge Great Tits are laying more eggs; thought the warming of the climate Great Tits starts to breed 5 days earlier comparing to data by A. Aleknonis (1958-1982); regarding earlier breeding of Great Tits in first broad, either prolonged period with higher temperatures second broad is relatively larger and initiated to lay earlier.
5

MAPPING RIPARIAN BUFFER ZONES IN CYPRESS CREEK REFUGE, ILLINOIS: LAND USE CHANGE IMPACT ON HABITAT USAGE FROM 1984-2014: PASSERINE PRESENCE AND CLASSIFICATION COMPARISONS

Burck, Michael Theodore 01 December 2017 (has links)
In response to recent declines, forested riparian wetland areas have become an increased conservation and management area of concern focusing on increasing biodiversity and promoting healthy ecosystem services. Additionally, passerine birds have also experienced a sharp global decline in that associated habitat. To mitigate further declines of both habitat and species numbers government programs and agencies have intensified conservation efforts. However, the practices employed are often assumed to be beneficial without conducting dedicated surveys to measure efficacy and practicality of current approaches. As such, visual evidence and statistics are often needed to promote or validate further support and funding for continuing with current polices or creating new focal areas and practices. This study strives to provide an inexpensive, efficient way to assess conservation areas based on a target species through a generalized and adaptive methodology. The Cypress Creek National Wildlife Refuge in southern Illinois provides an opportunity to do just that with a focus on songbirds. The methodology outlined in this study implements multiple remote sensing land use and land cover classification techniques utilizing Landsat imagery from 1984 to 2014 to create a temporal analysis of the region from pre-refuge era to current refuge designated era. Field surveys from the 2015 songbird summer breeding and fall migration seasons as well as vegetation surveys for field-truthing supplement the remote sensing results. The classification methodology incudes a combination of pan-sharpening Landsat images to a 15 m x 15 m spatial resolution, texture analysis, object based image analysis, and Random Forests to produce land use and land cover maps. For the sake of comparison the same classification process is performed with the untransformed, source images at 30 m x 30 m spatial resolution. Landscape metrics such as the interspersion and juxtaposition index and the contiguity index also provide further insight to temporal landscape patterns. At the completion of the study it was found that there was a minimal difference between the overall classification accuracy of transformed and untransformed images and that lowest overall accuracy in the study was 91% while the highest was 98%. The key survey statistics concluded that during the summer and fall observation periods songbirds in forested wetland areas had a propensity to utilize areas closest to the wetland edge as opposed to inland areas. Furthermore, during fall migration it was concluded that the mixed forest habitat type had a direct effect on observation numbers. Overall, with the aid of multiple landscape metrics, it was shown that the region was increasing in forested area, patch density, and contiguity; in response the passerines were using the area at a high rate, especially near wetland edges creating a sustainable focal area for conservation and management. The methodology and results in this study contribute to an ongoing effort to provide visual and statistical evidence that is reliable and accessible for policy making. The potential to manipulate the generalized methods used in this study to enhance any land use and land class classifications and apply to any targeted species certainly exists. Future studies will want to investigate the use of higher spatial resolution images or actively take reflectance recordings in the field and supplement the temporal maps with a multi-year dedicated species dataset for maximum benefit.
6

Isospora bocamontensis (Pereira et al., 2011) (Protozoa: Apicomplexa) em cardeais-amarelo Gubernatrix cristata (Vieillot) (Passeriformes: Emberezidae) / Isospora bocamontensis (Pereira et al., 2011) (Protozoa: Apicomplexa) in yellow cardinal Gubernatrix cristata (Vieillot) (Passeriformes: Emberezidae)

Pereira, Larissa Quinto 28 February 2011 (has links)
Conselho Nacional de Desenvolvimento Científico e Tecnológico / The yellow-cardinal (Gubernatrix cristata) is a passerine bird that occurs in southern Brazil, especially along the border with Uruguay and Argentina. It is an endangered bird and your population is decreasing due to loss and fragmentation of your habitats besides illegal capture. In Brazil, its captive breeding is regulated by the government agency and allows the maintenance of individuals in different places with different breeding systems. Among the parasites that affect passerines, the coccidia of the genus Isospora are the most easily found in both captive and free-living birds. Commonly cause injury to the intestinal tissue and could occasionally affect other organs. In this work, we describe a new species of Isospora in yellow-cardinal and also establish the occurrence of the protozoan and its relationship with factors such as sex, use of parasiticide products, type of cage, contact with feces, food type and frequency of cleaning in birds kept in captivity in the city of Santa Maria, Rio Grande do Sul, Brazil. / O cardeal-amarelo (Gubernatrix cristata) é um pássaro que ocorre no sul do Brasil, principalmente na fronteira com Uruguai e Argentina. É uma ave ameaçada de extinção e sua população está decrescendo devido a perda e fragmentação do seu habitat além da captura ilegal. No Brasil sua criação em cativeiro é regulamentada pelo órgão governamental e possibilita a manutenção dos indivíduos em vários locais com diferentes sistemas de criação. Os coccídeos do gênero Isospora estão entre os mais encontrados na ordem Passeriformes, tanto em aves cativas quanto em aves de vida-livre. Comumente causam injúrias no tecido intestinal, podendo ocasionalmente afetar outros órgãos. Neste trabalho pôde-se descrever uma nova espécie de Isospora em cardeais-amarelo e também estabelecer a ocorrência deste protozoário e relacionar com fatores como sexo, uso de produtos parasiticidas, tipo de recinto, contato com fezes, tipo de alimentação e frequência de limpeza dos recintos nas aves mantidas em cativeiro na cidade de Santa Maria, Rio Grande do Sul, Brasil.
7

Haemoproteus u pěvců: prevalence a dynamika infekce / Haemoproteus in passerines: Prevalence and infekction dynamics

Chalupová, Barbora January 2020 (has links)
The genera Haemoproteus and Plasmodium are widespread genera of blood parasites from phylum Apicomplexa. Both genera have dixenous life cycle and their definitive hosts belong to the order Diptera. Both parasites can be found in birds where asexual division takes place. The infection with genera Haemoproteus and Plasmodium is usually asymptomatic; during long lasting chronic phase relapses of the infection can occur. We gained 1 092 blood samples from 29 trapped species of passerines in Milovice forest during seasons 2017-2019. Haemosporidians were detected in 48 % of samples. The prevalence of genus Plasmodium was 16 %, the prevalence of genus Haemoproteus was 22 % and 10 % we could not specify the parasite. We have found six new lineages of genus Haemoproteus, provisionally named Haemoproteus lineages coccoc_1, coccoc_2, coccoc_3, coccoc_4, embcit, fricoe which total prevalence was 14 %. Lineage Haemoproteus sp. coccoc_1 was the most noticed one and its prevalence was 12 %. Plasmodium relictum clone Peng14-121Br2AF and isolate Cc_P1 was the second most prevalent (13 %). Infection dynamics was studied in samples gained in years 2014-2019. Forty individuals were examined between years and twenty-seven individuals were examined intraseasonally. Three individuals were trapped both intra- and...
8

Identifica??o e densidade de cocc?dios parasitas (Apicomplexa: Eimeriidae) de aves silvestres no Distrito de Cacaria, Munic?pio de Pira?-RJ / Identification and density of parasitic coccidia (Apicomplexa: Eimeriidae) of wild birds in the District of Cacaria, Municipality of Pira?-RJ

Oliveira, Mariana de Souza 31 August 2017 (has links)
Submitted by Celso Magalhaes (celsomagalhaes@ufrrj.br) on 2018-08-23T18:54:19Z No. of bitstreams: 1 2017 - Mariana de Souza Oliveira.pdf: 2345749 bytes, checksum: 613f695368567431340caa1eae7f5872 (MD5) / Made available in DSpace on 2018-08-23T18:54:19Z (GMT). No. of bitstreams: 1 2017 - Mariana de Souza Oliveira.pdf: 2345749 bytes, checksum: 613f695368567431340caa1eae7f5872 (MD5) Previous issue date: 2017-08-31 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Brazil is one of the 5 most megadiverse countries in the world, presenting 14% of all the biodiversity known worldwide. Brazil also has a greater tropical vegetation covering the world, presenting a high number of endemic species, becoming one of the most important countries in the world for investments in bird conservation. The district of Cacaria, in the municipality of Pira?, Rio de Janeiro, Brazil, has an extensive vegetation cover area, but is affected by local cattle breeding, as well as other anthropogenic actions. Birds can have a high diversity of parasites, such as ectoparasites, helminths and coccidia. Coccidian parasites are the main cause of enteritis, behavioral and reproductive changes in most species of birds. . Coccidia studies are relevant both to animal health and to knowledge of the biodiversity of these parasites. In this context, the objective of this study was to examine the feces of wild birds captured in fragments of Atlantic Forest in the district of Cacaria, in southeastern Brazil, to identify and quantify the coccidian parasites that were present, besides relating them to some ecological characteristics of birds. 14 expeditions were carried out on three fragments of Atlantic Forest in Cacaria, resulting in the capture of 143 birds, with 20 of them positive for coccidia. Among the positive samples, coccidia of Isospora and Eimeira classification were found in 12 species of birds. These coccidia were identified according to the literature, species of coccidia not described in the literature until the present moment were considered morphotypes. There was no relation between the bird species and the positive samples, with their respective oopds (Oocyst by defecation). Regarding the ecological characteristics, only living habits in forest environments were significant, showing that the birds of forest environments are less susceptible to infection. Regarding eating habits, there were no significant results / O Brasil ? um dos 5 pa?ses mais megadiversos do mundo, apresentando 14% de toda a biodiversidade conhecida mundialmente. O Brasil tamb?m tem uma maior vegeta??o tropical cobrindo o mundo, apresentando um elevado n?mero de esp?cies end?micas, tornando-se um dos pa?ses mais importantes do mundo para investimentos em conserva??o de aves. O distrito de Cacaria, no munic?pio de Pira?, Rio de Janeiro, Brasil, tem uma extensa ?rea de cobertura vegetal, mas ? afetado pela cria??o de gado local, al?m de outras a??es antr?picas. As aves podem ter uma alta diversidade de parasitas, como ectoparasitas, helmintos e coccidia. Os parasitas coccidianos s?o a principal causa de enterite, altera??es comportamentais e reprodutivas, na maioria das esp?cies de aves. Os estudos de coccidia s?o relevantes tanto para a sa?de animal quanto para o conhecimento da biodiversidade desses parasitas. Neste contexto, o objetivo deste estudo foi examinar as fezes de aves silvestres capturadas em fragmentos de Mata Atl?ntica no distrito de Cacaria, no sudeste do Brasil, para identificar e quantificar os parasitas coccidianos que estavam presentes, al?m de relacion?-los a algumas caracter?sticas ecol?gicas das aves. Foram realizadas 14 expedi??es em 3 fragmentos de Mata Atl?ntica em Cacaria, resultando em captura de 143 aves, com 20 delas positivas para cocc?dios. Dentre as amostras positivas foram encontradas cocc?dios de classifica??o Isospora e Eimeira, em 12 esp?cies de aves. Esses cocc?dios foram identificados de acordo com a literatura, as esp?cies de cocc?dios n?o descritas na literatura at? o presente momento foram consideradas morfotipos. N?o se obteve rela??o entre as esp?cies de aves e as amostras positivas, com seus respectivos oopds (Oocisto por defeca??o). Em rela??o as caracter?sticas ecol?gicas, apenas h?bitos de viv?ncia em ambientes florestais foi significante, apresentando que as aves de ambientes florestais s?o menos suscept?veis a infec??o. J? em rela??o aos h?bitos alimentares, n?o se obteve resultados significativos.
9

The links between dispersal and individual fitness : correlation or causality ? : exploring mechanisms using correlative and experimental approaches in a passerine bird species, the collared flycatcher / Lien entre dispersion et valeur sélective individuelle : corrélation ou relation de cause à effets ? : exploration des mécanismes

Germain, Marion 16 December 2014 (has links)
La dispersion est définie comme le mouvement d'un individu entre le site de naissance et le premier site de reproduction ou entre deux sites de reproduction. La dispersion se traduit par des échanges d'individus et des flux de gènes entre les populations et est donc reconnue comme un trait d'histoire de vie clé de part son rôle déterminant sur de nombreux processus écologiques et évolutifs comme la dynamique ou la génétique des population, la répartition spatiale des espèces ou encore la capacité des espèces à faire face aux changements brutaux induits par les activités humaines. Pourtant les conséquences de la dispersion en terme de valeur sélective individuelle restent mal connues malgré leur importance dans l'évolution de la dispersion. Le but de cette thèse est d'identifier plus précisément les conséquences de la dispersion en terme de valeur sélective individuelle en utilisant à la fois des approches corrélative et expérimentale dans une population sauvage de passereaux migrateurs, le gobe mouche à collier (Ficedula albicollis). Grâce à des données à long terme comprenant plus de 20 ans de suivi, des différences entre les individus dispersants et philopatriques ont pu être mises en évidence à la fois à l'échelle de la vie des individus et à l'échelle annuelle, celle de l'événement de reproduction. Les résultats mettent en évidence des effets de la dispersion dépendant à la fois des conditions et du phénotype des individus et soulignent donc le fait que la balance entre les coûts et les bénéfices est le résultat d'interactions subtiles entre l'environnement et les caractéristiques de l'individu. D'autre part, l'expérience de dispersion forcée a permis de démontrer clairement l'existence de coûts liés à l'établissement dans un environnement non familier que seuls certains individus sont capables de surmonter. Enfin, l'absence de différence dans les décisions majeures de reproduction une fois les individus établis, suggère que la dispersion doit majoritairement être adaptative, une fois les coûts de l'installation surmontés / Dispersal is commonly defined as the movement of an individual from its natal or previous breeding site to a new breeding site. Because dispersal involves movements of individuals and genes among populations, it is widely recognized as a key life history trait with strong effects on many ecological and evolutionary processes, such as population dynamics and genetics but also species spatial distribution or response to brutal environmental variations induced by human activities. Yet, the consequences of dispersal in terms of individual fitness remain poorly understood despite their crucial importance in the understanding of the evolution of dispersal. The aim of this PhD is to get better insights in the fitness consequences of dispersal using both correlative and experimental approaches at different scales, i.e. annual and lifetime scales, in a wild patchy population of migratory passerine bird, the collared flycatcher (Ficedula albicollis). Using a long term data set encompasses more than 20 years of data, differences between dispersing and philopatric individuals were showed both at a lifetime and annual scale. The results highlighted strong phenotypic- and condition-dependent effects of dispersal and underline that the balance between the costs and benefits of dispersal is likely to be the result of subtle interactions between environmental factors and individuals’ phenotype. Moreover, the experiment of forced dispersal demonstrated that dispersal might entail costs linked with settlement in a new habitat, which only some individuals may overcome. Nevertheless, the absence of difference in major fitness related decisions after settlement suggests that dispersal is mostly adaptive for individuals overcome such costs
10

The Evolutionary History, Demographic Independence and Conservation Status of Two North American Prairie Bird Species: The Greater Prairie Chicken and the Lark Sparrow

Ross, Jeremy D. 27 April 2011 (has links)
No description available.

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