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The Evolution of Menopause and Duration of Reproductive Life-span in Humans and it's Comparison with Social Mammals.
Fuxová, Helena ; Brůžek, Jaroslav (advisor) ; Blažek, Vladimír (referee)
This paper concludes basic information about reproductive life-span in humans, however the special emphasis is placed on a synthesis of available knowledge about the existence and evolution of menopause and postreproductive period. Based on published data, the paper focuses on the occurrence of these phenomena, not only in humans but also in other social mammals. Subsequently, this paper finds out that the termination of reproduction followed by postreproductive life-span is not only present in humans, but similar phenomena can be found also in other taxa. The special attention is given to the primates and the cetaceans, where the menopause phenomenon is being well studied. Moreover, to present a more complex and in-depth view into the topic, it is also crucial to mention a different point of view by the short insight into the existence of the menopause in other vertebrata and invertebrates. Moreover, there are compared phenomena of menopause and postreproductive period of humans and other representatives of the animal kingdom. Bachelor's thesis is the finding that menopause or end of reproduction followed by postreproductive life-span are phenomena more common than it is generally believed. The subsequent goal is a critical look at the main theories about the evolution of menopause in humans (" The...
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Vocal communication of cetaceans (Cetacea) with emphasis on development and learning
Zvěřinová, Adéla ; Šimková, Olga (advisor) ; Nevečeřalová, Petra (referee)
Vocal communication is the main mean of communication for cetaceans. Just like the species themselves, their repertoires are diverse, consisting of tonal, pulsed, and combined calls, with frequency and amplitude modulation. The two groups of cetaceans, Mysticeti (baleen whales) and Odontoceti (toothed whales), produce sounds of different parameters, mainly frequency, bandwidth, and duration. Both production and contextual learning can be found in cetaceans. It is used to acquire two types of sounds: signature calls and songs. Signature calls are present only in species living in stable groups or fission-fusion society. They are used as an identification tool to maintain cohesion and contact with conspecifics. Songs are present in most baleen whales, but only humpback and bowhead whales' change within and between seasons. They use vocal learning to conform to one type used by all individuals. It is also employed during vocal development in ontogenesis, together with maturation. Calves and juveniles' calls are chaotic, lacking in structure. With age, they gain stereotypy and resemble adults' repertoire. Key words: cetaceans, vocal communication, signature calls, vocal learning, cultural transmission
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Selfrecognition, selfawareness and other cognitive functions in cetaceans
Jachnická, Kristýna ; Šimková, Olga (advisor) ; Adamová, Dana (referee)
Self recognition is highly discused topic in cognitive sciences. Experiments on a level of behavioral (mirror test, reference tests of body parts using) show that animals usually are able to realize parts of their own body. There are several experimental evidence among cetaceans of this kind that proved that they are conscious of their own body parts (self awareness). There are also many other complex cognitive skills that can be predisposition to self recognition or that can prove that cetaceans are conscious of they own mind (self consciousness). Powered by TCPDF (www.tcpdf.org)
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Protection of marine mammals under International Law
Hloušek, Michal ; Žákovská, Karolina (advisor) ; Stejskal, Vojtěch (referee)
The present thesis begins with a brief overview of some of the most important international, mainly global conventions relevant to the protection of biological diversity in its entierety. Subsequent chapters then deal with some species or higher taxons of marine mammals, in particular with cetaceans, polar bears and pinnipeds. The aim was not only to analyse relevant international conventions, but also to discuss some interesting and precise questions that complete and form the conservation regime.
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The Evolution of Menopause and Duration of Reproductive Life-span in Humans and it's Comparison with Social Mammals.
Fuxová, Helena ; Brůžek, Jaroslav (advisor) ; Blažek, Vladimír (referee)
This paper concludes basic information about reproductive life-span in humans, however the special emphasis is placed on a synthesis of available knowledge about the existence and evolution of menopause and postreproductive period. Based on published data, the paper focuses on the occurrence of these phenomena, not only in humans but also in other social mammals. Subsequently, this paper finds out that the termination of reproduction followed by postreproductive life-span is not only present in humans, but similar phenomena can be found also in other taxa. The special attention is given to the primates and the cetaceans, where the menopause phenomenon is being well studied. Moreover, to present a more complex and in-depth view into the topic, it is also crucial to mention a different point of view by the short insight into the existence of the menopause in other vertebrata and invertebrates. Moreover, there are compared phenomena of menopause and postreproductive period of humans and other representatives of the animal kingdom. Bachelor's thesis is the finding that menopause or end of reproduction followed by postreproductive life-span are phenomena more common than it is generally believed. The subsequent goal is a critical look at the main theories about the evolution of menopause in humans (" The...
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Breeding of bottlenose dolphin (Tursiops truncatus) in captivity
Šablaturová, Tereza ; Petrtýl, Miloslav (advisor) ; Kuříková, Pavlína (referee)
The Thesis focuses on captive breeding of bottlenose dolphin (Tursiops truncatus) and its physical and behavioral aspects.
At the beginning there is current taxonomy of the species and his phylogeny and basic biology, including consequent threats caused by interaction with mankind.
The main part of the Thesis concentrates on the history of the captive breeding, shortlist of the theme parks that keep dolphins in captivity with emphasis on each continent and species which are bred there. Also, there are technical aspects of the breeding, such as diet, training, healthcare with accent on the diseases and their diagnostics while mentioning euthanasia of the bred individuals.
It's important to understand the true purpose of the marine mammal parks, which is usually misunderstood to be solely for entertainment purposes despite its high technical standards, while there should be aim for conservation of the species, education and research put first.
The attitude towards marine mammal parks is outlined at the end of the Thesis, followed by a list of organizations providing protection for the species bred in captivity.
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Effect of noise pollution on selected species of cetaceans
Burgerová, Anna ; Petrtýl, Miloslav (advisor) ; Kuříková, Pavlína (referee)
Sound in water tends to travel much faster than in air. Cetaceans started to use the hearing system as a tool for their communication and so this system must have been adapted during the evolution. Every species form his specific sound repertoire which is used mainly for food finding, detection of predator or other hazards, communication and reproduction.
Ocean ambient noise is created by natural sources of sound and man-made sounds (also called as anthropogenic sounds). Natural sounds are produced by marine organisms and processes like earthquakes, rainfall and so on. Anthropogenic sounds are made by man either intentionally or unintentionally and these sounds mostly disrupt the oceanic environment. Sound frequency and intensity level are the main factors when we determine the intensity of distortion in communication of Cetaceans. The most detrimental sounds are those with low frequency (from 10 to 500 Hz) and long-ranged propagation (hundreds of kilometers). Into this category we can include shipping and seismic surveys. In general, the most of anthropogenic sources of noise belong to this category. Other sources of anthropogenic noise are industrial activities, military sonar and acoustic deterrent and harassment devices (ADDs/AHDs).
Responses of Cetaceans to anthropogenic noise can be divided into three categories: physiological, behavioral and acoustic. The physiological reaction can be increasing metabolism, increasing baseline concentration of glucocorticoids in the blood and ultimately reducing immunity. Behavioral responses include changes in heading patterns and swim speed, changes in diving and breathing. Also included are social activities like food finding or nursing. Every change in vocalization represents acoustic responses.
With growing number of studies which prove a negative influence of anthropogenic noise on Cetaceans there is an increasing need to introduce effective measures which could reduce or limit this negative influence. For this purpose there are established marine protected areas and safety zones which avoid exposure to loud noise (circa 120 dB and more) thanks to their regulations. As well there was developed a technology to modify the ship equipment and the using of an air bubble curtain in the immediate area of the industrial activity shows efficiency in acoustic attenuation.
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