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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

Ontogeneze vokalizace u gibonů rodu Nomascus / The ontogeny of vocalisation in gibbons Nomascus

Hradec, Michal January 2016 (has links)
Knowledge of the ontogeny and development of vocalization in primates play a crucial role in understanding the evolution of the human language. Unlike the great apes, gibbons produce a remarkable vocal performance, which includes complex species- and sex-specific patterns. Many studies in the past focused on research of the acoustic pattern in adult individuals. Yet, it remains unclear how the males develop their sex-specific pattern of vocalization. This dissertation focuses on two specific periods in the ontogenetic development of acoustic structures in male Northern-white cheeked gibbons (Nomascus leucogenys) and Southern-yellow cheeked gibbons (Nomascus gabriellae). The results showed that the first time immature males (juvenile and adolescent) produced female acoustically structured great calls in duets with their mothers. How the great call was structured in immature males differed from the great call of their mothers; the difference being in spectro-temporal parameters from. The most significant difference between juvenile and adolescent males in the production of female vocalization was the presence of a twitter vocalization towards the end of their call. The results show that the twitter was a regular part of female vocalization in juvenile males around four years of age, while younger males produced this vocalization exceptionally. The second period in the ontogeny of vocalization in immature males (adolescent) was characterized by the fact that after five years of age, the development of the male acoustic structure begins. During this period, we did not observe the production of the female vocalization great call in any of the monitored Nomascus gibbon individuals. Results show that the ontogenetic process of the male song in Northern-white cheeked gibbons (N. leucogenys) did not develop in the same sequence as in adults which produced different notes and phrases. The immature male (adolescent male) first time developed the multi-modulation phrase (coda) and the staccato note (syllables) simultaneously at the beginning of this study, but, it was observed that they started producing the boom note four months later. Conversely, the development of the acoustic structure in male Southern-yellow cheeked gibbons (N. gabriellae) was characterized only by the development of a multi-modulation phrase. Development of the staccato syllables was not noted in this species during the study. The results support the interpretation that the development of the male acoustic structure closely corresponds to the growth of the vocal tract and physiological changes associated with reaching sexual maturity.
2

Vliv hlukového a světelného znečištění na hlasovou aktivitu kosa černého (&-lt;i&-gt;Turdus merula&-lt;/i&-gt;) / The impact of noise and light pollution on voice activity of Blackbird (Turdus merula)

Vlach, Martin January 2016 (has links)
Abstract Cities represent a new environment where organisms are exposed to different environmental conditions than the original natural habitats. This is essentially a noise and light pollution. The growing number of studies show that these factors can have a significant impact on voice activity of birds.Light pollution may alter the timing of vocalization.Urban noise can overlay the acoustic signals of birds, change the melody, volume, and the timing of singing. The main objective of this thesis was to investigate the influence of noise and light pollution to voice activity Blackbird (Turdus merula). In 2015 it was recorded vocalizations to 4 types of sites: a) on the site only with noise pollution (unlit busy road), b) on the site only with light pollution (Parks), c) on location with noise and light pollution (busy roads in cities), d) on the site without the noise and light pollution (forests). Recording was done with the help of voice recorders from early March until the end of May when the weather was good (no strong winds and storms) every week to thoroughly map the seasonal voice activity of the birds. Quiet location and localities with noise pollution have been in the woods near the town of Beroun near the D5 highway. Locations with light and noisy pollution is found in Hradec Kralove and Prague. In each locality they were searched individuals Blackbird and placed recorder into their territory. The recordings were taken 180 minutes before sunset, throughout the night and morning was the end of the recording 180 minutes after sunrise. The results showed the influence of the sites primarily on the morning vocalization when in the localities affected by light and noise vocalized significantly earlier than the quiet and noisy areas. In the evening times was vocalization without significant differences. The greatest intensity of vocalizations Blackbird was light-noisy areas, opposite to others. The evening was the greatest intensity of the sound recorded in quiet locations. Finally, the night vocalization has been demonstrated only in localities light-noisy.
3

Individuální hlasová variabilita a informace o rozeznávání predátorů obsažené ve vokální komunikaci morčat domácích (Cavia porcellus) / Information content in vocalization of guinea pigs (Cavia porcellus): individual distinction and recognition of predators

Baklová, Aneta January 2016 (has links)
Guinea pigs represent domesticated precocious rodents which became common pets. From the first day after birth they are fully vocal. This thesis was devoted to the vocalization of pups. The aim of the thesis was to 1) determine the age when the vocal individuality in whistle sound is demonstrable; 2) test possible ultrasonic signals emitted by young guinea pigs; 3) study the antipredator reactions and alarm calls to aerial (bird of prey) and terrestrial (dog) predators and human (control test). A total of 16 guinea pig pups were tested for vocal individuality, 28 pups for ultrasonic vocalization and 27 adolescents for predator recognition. When testing vocal ontogeny during the first 9 days after birth, I observed changes in temporal, frequency and parameter of intensity . When I test vocal individuality by cross-validated discriminant function analysis (DFA) based on ten acoustic parameters, calls were classified to correct animals with following success: day 1 = 71.9%, day 3 = 58.8%, day 5 = 53.10%, day 7 = 50.60% and day 9 = 63.10%. The highest frequency in whistle was 30.03 kHz. In predator discrimination reactions as freezing, fleeing and vigilance were observed. In the presence of dog, guinea pigs reacted for the longest time and most frequently by freezing. When confronted with a bird of prey, I observed for a longest time and most often fleeing and then freezing. When exposed to a human, guinea pigs showed mostly vigilance. Almost no vocalization was observed except for two events of alarm calls - drrr as in the presence of dog and chirrup as reaction to bird of prey. The following conclusions can be drawn from the presented results: 1) vocal individuality of guinea pigs is demonstrable immediately after birth and the rate of individually different vocal parameters changes with age; 2) guinea pigs are able to produce sound up to 30 kHz, i.e. within the ultrasound range, but signals of high frequencies are not crucial for their communication; 3) guinea pigs discriminate between terrestrial and aerial predators, but they emit alarm calls rather rarely.
4

Repertoár a specifika vokalizace papouška šedého (Psittacus erithacus) / Repertoire and specificity of vocalization in Grey parrot (Psittacus erithacus)

Kůrková, Petra January 2011 (has links)
The aim of the study was to map the repertoire of vocalization of four wild-caught grey parrots (Psittacus erithacus), two males and two females. Data were collected during nine days from June to November 2008 by recording of vocalization in standardized conditions. Recorded sounds (3 052) were categorized according to their characteristics using both visual inspection of spectrograms and listening. We found 70 different call types, which were combined into 18 bigger groups. We found no subject to use the whole repertoire. Important differences were found both between individuals and between males and females. almost all call types were used throuthout the whole period of recording. Model spectrograms of all call types are shown. Key words: grey parrot, Psittacus erithacus, repertoire, vocalization
5

Ontogeneze vokalizace papoušků šedých ve srovnání s člověkem / Vocal ontogenesis in grey parrots in comparison to humans

Roubalová, Tereza January 2016 (has links)
Human speech is considered to be unique means of communication. The beginnings of human vocalization, which develops into the speech, however, have some patterns or principles which can also be found in animal communication. It has been discovered that there are similarities between humans and animals in terms of social organization, neural control, cognition and function of vocal signals. Moreover, it seems that birds, parrots specifically, have closer parallels with humans in these respects than with other primates. Vocal ontogeny was, however, at least in parrots, investigated only marginally. Therefore it has become the subject of this study. African grey parrots (Psittacus erithacus) show a wide range of cognitive abilities and are thus suitable species for comparison with humans. The aim of this study was to map the early vocal development of African grey parrots until age of 11 weeks. Then it was possible to compare it theoretically with the early vocal development of children. The repertoire was mapped using video recordings of four fledglings of feral African grey parrots, which are in possession of FHS UK Prague. The recordings were analysed acoustically and visually with audio software Sound Forge Pro 11 and Sound Forge Audio Studio 10. After identifying the repertoire we used stage...
6

Referenční vokalizace papouška žako kongo (Psittacus erithacus) / Reference vocalization in African grey parrot (Psittacus erithacus)

Brojerová, Jana January 2013 (has links)
The ability to communicate referentially has been historically viewed as being uniquelly human. However, with the increasing amount of studies discussing the communicative faculty of animals in the context of the evolution of human language, there is now growing evidence that this ability is present in many animal species, too. Although we know a lot about mimetic abilities of domesticated African grey parrots' (Psittacus erithacus) and their competence to use human words in a referential way, we know very little about the elements of referentiality in their natural vocalization. Our goal in this work was to find, whether and in which context is functionally referential vocalization in this species of birds present. We were determining its presence by the experiment, in which we have exposed four captured African grey parrot, in the ownership of FHS UK Prague, to stimuli that in other animal species usually elicit functionally referential vocalization: predators and prefered type of food. We analysed the behaviour and vocalizations of the tested birds by analytic softwares Interact, respectively Soundforge 0.8. We find out, that despite the fact that birds reaponded to our experimental objects appropriatelly (i.e. "predators" caused more fear and the like), they give the major amout of...
7

Vztah velikosti na pozici v chóru u samců rosničky zelené (Hyla arborea) / Relationship between males' body size and position in the chorus in European tree frog (Hyla arborea)

STUPKOVÁ, Veronika January 2012 (has links)
Males of European tree frog are clustered in the chorus in order to attract females. Males were re-captured, their body size and position in chorus was recorded. Goal of this thesis was investigated a correlation between the males' body size and mating behaviour and their position in the chorus.
8

Jak, čím a proč cvakají při chůzi někteří zástupci turovitých (Bovidae)? / Clicking in bovids - basic parameters, origin and function?

ROCHOVÁ, Markéta January 2014 (has links)
Some species of hoofed animals produce clicking sound. This work analysed clicking parameters (dominant frequency, 25% quartile, 50% quartile, 75% quartile) of this species: Kuban Tur (Capra caucasica), Daghestan Tur (Capra cylindricornis) and Aoudad (Ammotragus lervia), which are clicking significantly. Clicks of each individual were recorded using solid state recorder Marantz PMD 620 with microphone. All clicks were analysed using program Avisoft-SAS Lab Pro Software, verze 5.0.01 (2010). Data were analysed using program STATISTICA, version 9 (ANONYMUS 2009). Individuals were compared using one-way ANOVA and discriminant analysis. Species and sexes were compared using discriminant analysis and nested ANOVA. Clicking parameters were correlated with age. A phylogenetic distribution of clicking was determined in Bovidae. Results suggest differences between individuals and species. Differences between sexes wasn't significant. Correlation with age was significant.
9

Sociální chování a akustická komunikace u netopýra velkého (Myotis myotis) / Social behaviour and acoustic communication in greater mouse-eared bat (Myotis myotis)

Porteš, Michal January 2014 (has links)
Order Chiroptera is characterized by great variability in foraging, roost and social strategies. Greater mouse-eared bat (Myotis myotis, Borkhausen 1797) is a model species of a bat in Europe and his seasonal organisation of population represents typical temperate bat cycle with females aggregated in large maternity colonies and solitery roosting males. Although the M.myotis is a model species, the majority of studies were focused on different aspects of maternity colonies biology and the biology of males is still poorly known. Recently founded aggregations of males of M. myotis in highway bridges allow to study social behaviour and acoustic communication of males on between individual level and discuss these findings with known information. While the bridge in Bernartice was inhabited by aggregation of males in individual roosts, in Voznice bridge we found besides males also a maternity colony of M. myotis. Harems of males were established from august until october. We found different pattern of seasonal roost occupancy in males with males with the highest level of mean occupancy having the highest level of female presence in roost. Vocalisation activity of males increased in august with highest level of activity in september. Males roosting closer to the flight entrance tended to have higher...
10

Akustická detekce potencionálního predátora u koně domácího (Equus caballus) / The acoustic detection of potential predator in domestic horse (Equus caballus)

Vidimská, Tereza January 2017 (has links)
Equidae belong to a group of large herbivores, which survival in natural environment depends beside others on their capability of fast predator recognition and detection. They can sensually recognise a possible threat in advance and react by immediate escape, which increases their survival. Also domestic horses still show very sensitive reaction to sudden (unexpected) stimuli. So we assume, that the ability to detect predator immediately is conserved despite of the long domestication process. The supportive indirect evidence is given by the successful breeding of the feral herds all over the world. However, studies showing the direct reaction of domestic horse toward the canids (as the most common predators), are still absent. Aim of the work was to find, if the horses (Equus caballus) could recognize acoustic sign of dogs like predators and if they could recognize the level of potential threat according to the number of predators, similarly as their wild ancestors. The recordings of barking of big dog breeds were obtained and modified. The final recording contained the set of barking coming from one individual or three different. The recording was played to the experimental horses, under controled conditions, together with white sound as a control. The reactions were recorded. Altogether 12 horses out of...

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