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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.
111

Efeito da paisagem sonora na detectabilidade acústica de anuros

Guimarães, Francisco Péricles Branco Bahiense 21 December 2017 (has links)
Submitted by Marcio Emanuel Paixão Santos (marcio.santos@ucsal.br) on 2018-05-04T20:56:14Z No. of bitstreams: 2 DISSERTACAOFRANCISCOGUIMARAES.docx: 2450268 bytes, checksum: bae026f7f497d1377ce648b34ca273b6 (MD5) DISSERTACAOFRANCISCOGUIMARAES.pdf: 1513020 bytes, checksum: 5e830a7d625f9e4969048192a6f90e85 (MD5) / Approved for entry into archive by Rosemary Magalhães (rosemary.magalhaes@ucsal.br) on 2018-05-08T14:30:15Z (GMT) No. of bitstreams: 2 DISSERTACAOFRANCISCOGUIMARAES.docx: 2450268 bytes, checksum: bae026f7f497d1377ce648b34ca273b6 (MD5) DISSERTACAOFRANCISCOGUIMARAES.pdf: 1513020 bytes, checksum: 5e830a7d625f9e4969048192a6f90e85 (MD5) / Made available in DSpace on 2018-05-08T14:30:15Z (GMT). No. of bitstreams: 2 DISSERTACAOFRANCISCOGUIMARAES.docx: 2450268 bytes, checksum: bae026f7f497d1377ce648b34ca273b6 (MD5) DISSERTACAOFRANCISCOGUIMARAES.pdf: 1513020 bytes, checksum: 5e830a7d625f9e4969048192a6f90e85 (MD5) Previous issue date: 2017-12-21 / A poluição sonora é um problema cada vez mais evidente no cotidiano das grandes cidades no mundo moderno, e o efeito desse ruído antrópico em áreas naturais e urbanas tem sido alvo de inúmeras investigações. O estudo da paisagem sonora vem se tornando uma ferramenta importante para o entendimento da dinâmica acústica ambiental. A determinação do efeito da paisagem sonora sobre a detectabilidade acústica de anuros na região metropolitana de Salvador-BA, identificando e analisando os componentes acústico da paisagem, através de gravações de áudio automatizadas. 14 anuros em atividade acústica foram identificados em duas estações distintas, seca e chuvosa. O Escalonamento multidimensional não métrico (NMS) demostrou como os componentes da paisagem sonora se organizam e relacionam com as espécies de anuros identificadas nas gravações. Nessa análise podemos observar a relação de algumas espécies de anuros com a covariante decibel (dBA), testamos modelos de detectabilidade a partir dessa variável ambiental e encontramos valores bem distintas, Pseudopaludicola mystacalis apresentou maior detectabilidade entre os anuros estudados (p = 100%), seguido do Scinax auratus (89,6%) e Leptodactylus vastus (p= 70,83%). O efeito da paisagem sonora nos anuros foi diferente para cada espécie estudada, enquanto o P.mystacalis parece não se incomodar com o nível de ruído das localidades o L. vastus mudanças comportamentais em ambiente mais ruidoso. Os estudos de Paisagens Sonoras são registros permanentes de acontecimentos de uma determinada localidade, numa determinada época. O que torna as gravações desse trabalho ferramentas importantes para analises futuras dessas duas áreas de estudos.
112

Ecologie et diversité acoustique des milieux aquatiques : exploration en milieux tempérés / Acoustic diversity and ecology of freshwater environments : exploration in temperate environments

Desjonquères, Camille 21 November 2016 (has links)
Une grande diversité d’animaux produit des sons pour communiquer, s'orienter, ou lors de la réalisation d'actes comportementaux comme la prise de nourriture. Ces sons ne se répartissent pas aléatoirement dans l'espace et le temps suggérant l'existence de règles d'assemblage sonore qui structurent les populations et communautés acoustiques. Les environnements d'eau douce, et en particulier les mares, sont considérés comme les réservoirs d'une importante diversité biologique, et donc potentiellement abritant un nombre significatif d'espèces produisant des sons. Cependant la diversité acoustique de ces milieux naturels n'a jamais été explorée.L'objectif principal de cette thèse est d'explorer pour la première fois la diversité acoustique présente dans les milieux d'eau douce en climat tempéré en étudiant les structures des populations et communautés acoustiques et en explorant les processus pouvant déterminer ces structures.Une revue bibliographique sur la production sonore par les organismes d'eau douce ainsi que des enregistrements d'espèces cibles effectués en laboratoire révèlent qu'une diversité acoustique particulière existe dans les environnements d'eau douce en milieux tempérés. Pour comprendre comment cette diversité est structurée, les communautés acoustiques de trois mares situées dans des environnements différents ont été enregistrées et suivies au cours du temps. Cette étude révèle que les trois mares sont caractérisées par des communautés acoustiques riches et distinctes ayant des dynamiques spatio-temporelles spécifiques. Les facteurs potentiels structurant les communautés acoustiques d’eau douce ont été recherchés en testant si la composition de communautés acoustiques dans six bras morts de la plaine d'inondation du Rhône était liée à des variables environnementales. Nos résultats montrent que les communautés acoustiques des bras morts sont significativement liées à une variable environnementale : le degré de connectivité entre les bras morts et le lit principal de la rivière. Ce résultat suggère un rôle clé de cette variable dans les règles d'assemblage des communautés. Enfin, pour comprendre les processus possibles liant la production de sons et l'environnement naturel, une population de l'insecte aquatique Micronecta scholtzi a été suivie par des enregistrements acoustiques dans une mare méditerranéenne. Le niveau d'activité acoustique de M. scholtzi a été estimé de façon continue à l'aide d'un réseau de 12 capteurs sonores synchronisés. L'activité acoustique était caractérisée par un rythme circadien, dont les propriétés étaient perturbées par la diffusion expérimentale d'un bruit d'origine anthropique. Cette expérience révèle que les effets de la pollution sonore peuvent être observés à l'échelle d'une population d'insectes aquatiques.Ce travail montre ainsi l'existence d'une diversité acoustique dans les milieux d'eau douce et identifie des relations entre production acoustique et facteurs environnementaux. Ce travail ouvre également des perspectives intéressantes d'utilisation de l'acoustique pour aborder des problématiques d'écologie fondamentale et appliquée en milieu d'eau douce. / An important diversity of animal species produces sounds during communication, orientation, movement, or prey-predator acts. These sounds are not distributed randomly in space and time and are therefore thought to follow assembly rules forming either acoustic populations or acoustic communities. Freshwater environments and ponds in particular, are considered as primary resources for biological diversity and as such host a potentially significant number of soniferous species. However the acoustic diversity of these natural environments remains totally unexplored.The main aim of this PhD was to explore for the first time the acoustic diversity found in temperate freshwater by studying the patterns and structural processes of a selection of acoustic populations and communities recorded in several types of freshwater environments. A review of the literature on sound production by freshwater organisms along with laboratory recordings of target species revealed that a valuable acoustic diversity can be found in temperate freshwater environments. To understand how the acoustic diversity is structured, the acoustic communities of three temperate ponds were acoustically monitored. This study revealed that the three ponds were characterized by rich and distinct acoustic communities with specific spatio-temporal dynamics. To further understand the potential factors structuring freshwater acoustic communities, environmental variables were assessed along with the composition of acoustic communities found in six secondary channels of the Rhône riverine floodplain. Two environmental variables were investigated: the water temperature and the level of lateral connectivity of the secondary channels to the main river. Acoustic communities in the Rhône riverine floodplain were clearly structured by lateral connectivity suggesting a role of this key variable as an assembly rule. Finally to understand the possible processes linking animal acoustics and the natural environment, a population of aquatic insect, Micronecta scholtzi, was acoustically monitored in a Mediterranean pond. The level of M. scholtzi acoustic activity was assessed continuously using a network of twelve synchronised acoustic sensors. The acoustic activity of \textit{M. scholtzi} showed a regular daily pattern that was modified in amplitude and phase by the playback of an anthropogenic noise. This experiment revealed that the effects of noise pollution may emerge at an aquatic insect population level. This PhD unraveled the existence of a significant amount of unexplored acoustic diversity in freshwater environments and identified links between acoustics and the environment. This research opens interesting perspectives in the use of acoustic to tackle fundamental and applied ecological questions in freshwater environments.
113

The Whistle caller concept - Signature whistles as call-over signals for Bottlenose dolphins (Tursiops truncatus) under human care

Rylander, Tilde January 2021 (has links)
Dolphins use stereotyped, individually distinctive, frequency modulated whistles, referred to as signature whistles, in order to broadcast their identity. In this study, we trained six dolphins at Kolmården Zoo, Sweden, to be called over, either upon hearing their own signature whistle (SW) or upon hearing a biologically irrelevant ”trivial” sound (TS), with the aim to prove the Whistle caller concept. The Whistle caller concept is based on the fact that dolphins occasionally use other dolphins’ signature whistles in order to address specific group members and convene.  Our hypotheses were that (1) dolphins call-over trained using their SW would learn the behaviour faster than dolphins trained using TSs, and (2) dolphins trained with their SW would be able to discriminate between different SWs better than dolphins trained with a TS would be at discriminating between different TSs.  Three out of three dolphins were successfully call-over trained using their SW, and two out of three dolphins using their assigned TS. When discriminating between different sounds, two of the dolphins trained using their SW performed significantly better than one of the dolphins trained using a TS. However, there were large intra-group differences in the results, indicating that we cannot eliminate the possibility that these results stem from individual differences in these dolphins’ ability to learn new behaviours overall, rather than an understanding of the sounds they heard. We suggest that future studies focus on (1) male-female differences in discrimination success when applying the Whistle caller concept, (2) how the characteristics of the trivial sounds affect discrimination success, and (3) the option of calling more than one animal at a time by sending out several SWs in succession.
114

Die Akustik der Anzeigerufe der Frösche - Einflüsse ihrer Umwelt und Biologie im Kontrast zur ihrer stammesgeschichtlichen Verwandtschaft

Emmrich, Mike 30 July 2020 (has links)
In ihrer stammesgeschichtlichen Entwicklung haben, neben Säugetieren, Vögeln und Insekten, auch Froschlurche ein umfangreiches Repertoire an akustischen Signalen zur Identifizierung arteigener Individuen und anlocken potenzieller Paarungspartner entwickelt. Diese sogenannten Anzeigerufe sind dabei für jede Art einzigartig. Beobachtungen zeigen aber, dass es neben dieser Artspezifität, auch Ähnlichkeiten in den Anzeigerufen zwischen nicht näher verwandten Arten existieren. Es stellt sich daher die Frage woher diese Ähnlichkeiten stammen. Stellen diese Ähnlichkeiten eine Anpassung an die Bedingungen der Lebensräume dar (konvergente Evolution) oder sind sie ein Ergebnis der stammesgeschichtlichen Entwicklung der Arten (divergente Evolution). Zur Klärung dieser Frage habe ich Anzeigerufe von ca. 1500 Arten aus den unterschiedlichsten Lebensräumen unseres Planten gesammelt und ausgewertet. Eine Korrelation der gemessenen akustischen Eigenschaften (z. B. dominante Frequenz) mit der Phylogenie der Amphibien sollte dabei klären, inwieweit die Phylogenie mit diesen akustischen Eigenschaften verknüpft ist. Vergleiche zwischen verschiedenen Kategorien aus Morphologie, Verhalten und Lebensraum in Bezug auf die akustischen Eigenschaften wiederum sollten mögliche Anpassungen der akustischen Eigenschaften herausstellen. Es stellte sich am Ende heraus, dass einige akustische Eigenschaften (z. B. dominante Frequenz) sowohl ein Ergebnis einer divergenten Evolution sind, als auch einer konvergenten Evolution. Zusätzlich war es mir möglich die Anzeigerufe in separate Gilden einzuteilen, die ähnliche strukturellen Eigenschaften aufweisen. Gilden in die Arten unabhängig von ihren verwandtschaftlichen Beziehungen eingeordnet werden können. Ein Werkzeug was Vergleiche zwischen Arten anhand ihrer Akustik vereinfacht und die Möglichkeit gibt zu verstehen wie Arten die Bedingungen ihrer Lebensräume auf ähnliche akustische Weise nutzen. / Beside mammals, birds and insects also anurans developed at their evolutionary history a wide repertoire of acoustic signals to identify conspecific individuals and to attract possible mating partners. These so-called advertisement calls are unique to every single species. However, beside this species-specific uniqueness we can also observe astonishing similarities among advertisement calls of not close related species. Therefore, there is the question of where these similarities came from. Are these similarities adaptations to conditions to similar biology’s and environments and so a result of a convergent evolution or these similarities arose by the anuran phylogeny and represent a divergent evolution? To answer these questions I collected and measured advertisement calls of ca. 1500 anuran species around the globe of different living habitats. A correlation between phylogeny and acoustic properties (e.g. dominant frequency) could show the influence of the phylogeny at the evolved acoustic traits. Comparisons among different categories of morphology, behaviour and habitat concerning the acoustic traits could show possible adaptations. The result of my research showed that some structural and spectral properties are a consequence of the phylogenetic history as well as an adaptation to conditions of biology and environment. Both, the divergent and the convergent evolution place a role in these cases. Additional I managed to introduce a system to order anuran advertisement calls into distinct guilds. These guilds show how different species uses their acoustic properties in a similar matter. An additional tool to make comparisons among species easier and to understand how anuran uses environments in a similar acoustic way.
115

Využití bioakustických přístupů pro studium interakcí druhů a druhové bohatosti ptačích společenstev / Application of bioacoustic approaches in investigation of bird species interactions and community species richness

Vokurková, Jana January 2021 (has links)
Birdsong is one of the most fascinating communication tools in the animal kingdom, whether it is used for attracting a mate or in territory defense. In my dissertation, I present evidence that we can successfully study the role of birdsong in territorial behaviour, its seasonal variability, and ultimately its role in evolutionary processes thanks to modern bioacoustic and ecoacoustic approaches. By combining the bioacoustic approach with molecular analyses, I demonstrate that in the model system of two closely related passerine species, the heterospecific song convergence in their secondary contact zone is based on cultural transmission, and not on interspecific hybridisation and/or gene introgression. My dissertation further extends into the tropical zone, which is generally characterized by less pronounced environmental seasonality compared to the temperate zone. The study of potential seasonality in singing activity and the proportion of vocalizing species in this zone therefore requires year-round monitoring, which is possible thanks to the quite recent development of automated recording units (ARU). First, we confirmed that using ARU provides very similar estimates of community composition, species richness, and abundance to traditional field methods (point counts) in the specific conditions...
116

Causes and Consequences of Urban-associated Song Variation: A Study of Vocal Behavior in the Northern Cardinal (<i>Cardinalis cardinalis</i>)

Narango, Desiree Lynn 22 June 2012 (has links)
No description available.
117

An analysis of phonotactic behaviour in the cricket Gryllus bimaculatus

Sarmiento-Ponce, Edith Julieta January 2019 (has links)
This thesis represents a comprehensive examination of the phonotactic behaviour (i.e. attraction to sound) of the female Gryllus bimaculatus under laboratory conditions. Chapter 2 is the first study to analyze the effect of substrate texture on walking performance in crickets. Substrate texture is found to play an essential role in the phonotactic responses of G. bimaculatus. Smooth substrate texture has a detrimental effect due to slipping, whereas a rough texture results in optimal walking performance due to the friction with the walking legs. Chapter 3 represents the first detailed lifetime study analysing phonotaxis in crickets. My results demonstrate that the optimal age to test phonotaxis in G. bimaculatus females is from day 7 to 24 after the final moult. I also found that selectiveness was persistent with age. These findings contradict the female choosiness hypothesis. This study is also the first to describe the effect of senescence on phonotaxis in insects, as responsiveness decreases with age. Chapter 4 compares the phonotactic behaviour of female crickets from different laboratory-bred colonies. From six tested cricket lab colonies, I found three groups statistically different from each other. Females raised under laboratory conditions at the University of Cambridge and Anglia Ruskin University were most reponsive at a frequency of 4.5 kHz, whereas females bred in Tokushima University in Japan were tuned towards a higher frequency of 5 kHz. These results suggest a degree of artificial allopatric speciation. Comparisons with crickets bred under low-quality conditions in a local pet shop demonstrate a loss of responsiveness, indicating that breeding conditions have a direct effect on phonotactic responsivity. Chapter 5 is the first study to report the presence of phonotaxis in males of G. bimaculatus. Previously it was unknown if G. bimaculatus males were able to perform phonotaxis, given that they were only recognised as endurance signal producers. In the present study, only 20% of the studied males (N=70) performed a weak phonotactic response. This finding has potential ecological implications in terms of male cricket territory establishment, and male-male interactions in the wild, which are discussed. Chapter 6 explores the song pattern recognition of the female G. bimaculatus by changing the duration of either the first, second or third pulse of the chirps. A long first pulse decreased the phonotactic response whereas phonotaxis remained strong when the third pulse was long. Chirps with three pulses of increasing duration of 5, 20 and 50 ms elicited phonotaxis, but the chirps were not attractive when played in reverse order. The data are in agreement with a mechanism in which processing of a sound pulse has an effect on the processing of the subsequent pulse, as outlined in the flow of activity in a delay-line and coincidence-detector circuit.
118

Offshore wind farms - ecological effects of noise and habitat alteration on fish

Andersson, Mathias H. January 2011 (has links)
There are large gaps in our understanding how fish populations are affected by the anthropogenic noise and the alteration of habitat caused by the construction and operation of offshore wind farms. These issues are of great importance as the construction of offshore wind farms will increase all over the world in the near future. This thesis studies these effects with a focus on fish. The wind turbine foundations function as artificial reefs and are colonized by invertebrates, algae and fish. The epibenthic assemblages are influenced by factors such as hydrographical parameters, time of submergence, distance to natural hard bottom, material and texture (PAPER I, II). Once an epibenthic assemblage has been developed, fish utilize it for different ecosystem services such as food, shelter, and spawning and nursery area. Benthic and semi-pelagic species show a stronger response to the introduced foundation than pelagic species, as it is the bottom habitat that has mainly been altered (PAPER I, II). Pelagic species could be positively affected by the increased food availability - but it takes time and the effect is local. Construction noise like pile driving creates high levels of sound pressure and acoustic particle motion in the water and seabed. This noise induces behavioural reactions in cod (Gadus morhua) and sole (Solea solea). These reactions could occur up to tens of kilometres distance from the source (PAPER III). During power production, the wind turbines generate a broadband noise with a few dominating tones (PAPER IV, V), which are detectable by sound pressure sensitive fish at a distance of several kilometres even though intense shipping occurs in the area. Motion sensitive species will only detect the turbine noise at around a ten meter distance. Sound levels are only high enough to possibly cause a behavioural reaction within meters from a turbine (PAPER IV, V). / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3, 4 and 5: Manuscripts.
119

Caracteriza??o do repert?rio ac?stico do botocinza, sotalia guianensis, e impacto de embarca??es no nordeste do brasil

Martins, Dalila Teles Le?o 26 April 2010 (has links)
Made available in DSpace on 2014-12-17T15:36:59Z (GMT). No. of bitstreams: 1 DalilaTLM_DISSERT.pdf: 2036255 bytes, checksum: ed8754e17f7a4951187f5fb000aa8918 (MD5) Previous issue date: 2010-04-26 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / The wide distribution along the Brazilian coast of specie Sotalia guianensis has been growing interest in searchers on the ecology of this species, addition to commercial interests by whalewatching. This work described the accoustic repertory of S. guianensis and their behavior associated and found if underwater noises affect this repertorie in Pipa-RN. It were analyzed 18:49h of recordings maked between april and june/2009. It were found 3258 whistles, 289 calls, 873 clicks and no gargle. The frequencies range of guiana dolphins was 1 a 48kHz and may be related to system response recorder and population s regionalization. The frequencies overlaps the noise made by motorboats, schooners and water bomb. The behavior travelling ocurred siletly in 72,58% and socialization presented no sound (56,4%) and presence of sound (43,6%). This great absence of sound may be relacioned to saving energy, probably because in this behaviors they can use physical and visual contacts. The foraging presented highest records of all class noise with 46,84% clicks, 33,84% whistles and 9,02% calls. All this sounds occurred differently in each behavior (travelling: x2 = 134,35 df = 3 p = 0,0001; foraging: x2 = 19,83 df = 3 p= 0,00018 and socialization x2 = 60,35 df = 3 p = 0,0001). It was possible to determine that underwater noise cause changes in the repertorie and does a considerable increase in whistle s number and reduce clicks. Also occurs changes in some whistles (FI: t=2,42, p=0,015; FF: t= -2,22, p=0,025), calls (FMI: t= -3,13, p=0,001; FMA: t= -3,49, p=0,0005; FD: t= -2,21, p=0,027; D: t=2,89, p=0,004) and clicks parameters (D: t= -3,85, p=0,0001; I: t= -5,32, p=0,0001) during presence of noise. These changes may be a strategy of these animals to win this sound barrier. We can not say which noise has more impact, ix however the water bomb seems to affect more the clicks and the motorboats seems to affect the others sounds. Little is know about auditive sensibility of this specie, but daily exposure to this noise may cause damage and this specie appears to have residence. The specie conservation is necessary because the population already seems to suffer damage as decrease in length of stay, number of individuals entering the inlet and the apparent diminution in the foragind during vessels presence and control standards and ambiental education can help. So, we can advance in knowledge about the ecology of this specie especially when it come to bioacoustics and their behaviors associated and reveals some of the impacts that the noise have brought to this population / A ampla distribui??o na costa brasileira da esp?cie Sotalia guianensis tem feito crescer o interesse pelos pesquisadores sobre a ecologia dessa esp?cie, al?m de interesses comerciais atrav?s do turismo de observa??o. Esse trabalho descreveu o repert?rio ac?stico S. guianensis e suas associa??es comportamentais e ainda, verificou se ru?dos subaqu?ticos de motores afetam o padr?o desse repert?rio, na regi?o de Pipa/RN. Foram analisadas 18:49h de grava??es realizadas entre os meses de abril e junho de 2009. Foram encontrados 3258 assobios, 289 gritos, 873 sequ?ncias de estalos e nenhum registro de gargarejo. A faixa de frequ?ncia dos botos variaram de 1 a 48kHz, que pode estar relacionada com a taxa de amostragem de 96kHz e com a regionaliza??o das popula??es. Essa faixa se sobrep?e as faixas utilizadas pelos ru?dos produzidos por lanchas, escunas e uma bomba d ?gua. Nas associa??es comportamentos e ac?stica, o estado de deslocamento ocorreu em 72,58% com aus?ncia de som e a socializa??o apresentou aus?ncia (56,4%) e presen?a de sons (43,6%). Essa aus?ncia de som pode estar relacionada com a economia de energia, visto que nesses comportamentos muitos eventos envolvem contatos f?sicos e visuais. A alimenta??o apresentou os maiores registros de todas as classes sonoras, com 46,84% de estalos, 33,84% de assobios e 9,02% de gritos. Todos os sons ocorreram com diferen?as significativas dentro de cada estado comportamental (deslocamento: x2 = 134,35 df = 3 p = 0,0001; alimenta??o: x2 = 19,83 df = 3 p= 0,00018 e socializa??o x2 = 60,35 df = 3 p = 0,0001). Com rela??o aos ru?dos, foi poss?vel verificar que esses sons causam modifica??es na vocaliza??o, com aumento consider?vel no n?mero de assobios e redu??o dos estalos. Ocorre, tamb?m vii altera??es de alguns par?metros dos assobios (FI: t=2,42, p=0,015; FF: t= - 2,22, p=0,025), gritos (FMI: t= -3,13, p=0,001; FMA: t= -3,49, p=0,0005; FD: t= -2,21, p=0,027; D: t=2,89, p=0,004) e estalos (D: t= -3,85, p=0,0001; I: t= -5,32, p=0,0001) durante a presen?a desses sons. Essas modifica??es podem ser uma estrat?gia que essa popula??o est? desenvolvendo para vencer a barreira dos ru?dos. N?o se pode afirmar qual dos tr?s ru?dos analisados causa maior impacto, entretanto a bomba d ?gua parece afetar mais os estalos, aumentando os valores de seus par?metros e a lancha parece afetar mais as outras classes sonoras. Pouco se sabe sobre a sensibilidade auditiva dessa esp?cie, mas exposi??es di?rias aos ru?dos podem trazer danos e essa esp?cie aparenta ter resid?ncia. Medidas para mitiga??o, como normas de controle das embarca??es e educa??o ambiental s?o necess?rias para a conserva??o da esp?cie, visto que a popula??o j? aparenta sofrer com danos como diminui??o do tempo de perman?ncia e n?mero de indiv?duos que entram na enseada, al?m da aparente diminui??o da alimenta??o durante a presen?a de embarca??es. Dessa forma, avan?a-se no conhecimento sobre a ecologia dessa esp?cie, principalmente quando se trata de bioac?stica e suas associa??es comportamentais, al?m de revelar alguns dos impactos que os ru?dos tem trazido para essa popula??o
120

Makroekologie a makroevoluce ptačího zpěvu / Macroecology and macroevolution of birdsong

Mikula, Peter January 2020 (has links)
Birdsong is one of the most astounding natural sounds which profoundly shaped our evolutionary thinking since the 19th century. Despite a strong interest in birdsong for over 100 years, our understanding of birdsong ecology and evolution over large spatial and phylogenetic scales is still very fragmentary. Answering many basic questions requires a global synthesis covering vast diversity of extant bird species and adoption of multidisciplinary approaches. In presented dissertation thesis, my co-workers and I have explored important patterns in macroecology and macroevolution of song in passerines (Order: Passeriformes), the most diverse and widespread bird order. We have focused on three key song phenomena: (1) song complexity, (2) song frequency and (3) the presence of song in female birds. We have exploited birdsong "big data" available on public citizen science databases and other open sources in order to fill several important gaps in the current knowledge. These data were analysed by a combination of phylogenetically-informed cross-species analyses and spatial macroecological approaches. Since the publication of Darwin's seminal work, elaborated songs are generally agreed to be the result of sexual selection. We developed a simple but reliable song complexity metric to explore a global diversity in...

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