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Geographical variation of localisation in vertebrates
Cinerová, Michaela ; Petrusková, Tereza (advisor) ; Turčoková, Lucia (referee)
Sound expressing is common for a big amount of animal species, mostly when communicating with individuals of their own or other species. Acoustic communication can be used especially in situations or in the environment where an individual does not see a signal receiver well (confusing environment, at night or long distance). It's well-known that the individual species have their own characteristic acoustic expressions. However, these can differ also within the species itself, either in time or in space. This study is concerned just with variability of inter-species vocal communication of all vertebrates in space. Its purpose is to map at which animal species vocalization vary in space. Furthermore, it deals with searching for causes of origin of this variability, such as genetic differences among particular groups of populations, environmental and learning effects etc. within various animal species. In the last part, it tries to answer the question whether the spatial variability of acoustic signals could influence separation of new species and thus have evolutionary consequences.
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Morphological variation of Cameroonian sunbirds
Bovšková, Denisa ; Hořák, David (advisor) ; Chmelová, Eliška (referee)
5 Abstract Morphological traits give information about the adaptations of the studied species, the resources, which it uses, and they can generally tell us about the use of ecological space. Intraspecific morphological variability reflects various adaptations of local populations thus variability reflect different way of life. The subject of this thesis is an ecologically interesting group of specialized tropical songbirds - Sunbirds (Nectarinidae). The taxon exhibits number of adaptations to specific food collecting a combination of nectarivory and insect hunting. I focused here on the intraspecific variability of three species (Cyanomitra oritis, Cinnyris reichenowi and C. bouwieri) living in different habitats in Cameroon. The aim of this work was to find out in what morphological characters are this species sexually dimorphic. Furthermore, if their populations living in remote locations differ? Finally, if all studied species show similar trend of intraspecific variability of the traits, which could have common ecological causes. The following traits were measured: wing and tail feather length, beak dimensions, total body weight and other characters. The analysis is based on field data collected between 2003 and 2015 and museum collections. Overall, we collect information about ca. 1200 individuals for...
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Morphological variation of Cameroonian sunbirds
Bovšková, Denisa ; Hořák, David (advisor) ; Chmelová, Eliška (referee)
5 Abstract Morphological traits give information about the adaptations of the studied species, the resources, which it uses, and they can generally tell us about the use of ecological space. Intraspecific morphological variability reflects various adaptations of local populations thus variability reflect different way of life. The subject of this thesis is an ecologically interesting group of specialized tropical songbirds - Sunbirds (Nectarinidae). The taxon exhibits number of adaptations to specific food collecting a combination of nectarivory and insect hunting. I focused here on the intraspecific variability of three species (Cyanomitra oritis, Cinnyris reichenowi and C. bouwieri) living in different habitats in Cameroon. The aim of this work was to find out in what morphological characters are this species sexually dimorphic. Furthermore, if their populations living in remote locations differ? Finally, if all studied species show similar trend of intraspecific variability of the traits, which could have common ecological causes. The following traits were measured: wing and tail feather length, beak dimensions, total body weight and other characters. The analysis is based on field data collected between 2003 and 2015 and museum collections. Overall, we collect information about ca. 1200 individuals for...
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Environment and avian song: case of South African birds
Mikula, Peter ; Albrecht, Tomáš (advisor) ; Linhart, Pavel (referee)
Relationship between animal signalization and environmental conditions, where these species are living, is one of crucial topics of ecology. Using two complementary statistical approaches (fourth-corner and RLQ analyzes) I investigated geographical variation in parameters of bird vocalization in South Africa (RSA) and Lesotho. Altogether, I used nine quantitative and five qualitative acoustic traits for 472 bird species and nine environmental variables which could significantly influence parameters of their vocalization. My results supported findings of previous studies about the important effect of body size on species-specific vocal characteristics. In passerines, analyzes corrected for body size showed that the number of elements and element types were increasing with variability of natural conditions and were highest in very arid and climatically unpredictable areas. Element and element type rate were positively associated with altitude. Minimal song frequency in passerines and frequency range of vocalization in other birds were negatively correlated with average temperature of warmest and coldest month of the year, respectively. Similarly, environmental variables significantly influenced distribution of several qualitative song traits in passerines. Passerines, where female song and...
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Geographical variation of localisation in vertebrates
Cinerová, Michaela ; Petrusková, Tereza (advisor) ; Turčoková, Lucia (referee)
Sound expressing is common for a big amount of animal species, mostly when communicating with individuals of their own or other species. Acoustic communication can be used especially in situations or in the environment where an individual does not see a signal receiver well (confusing environment, at night or long distance). It's well-known that the individual species have their own characteristic acoustic expressions. However, these can differ also within the species itself, either in time or in space. This study is concerned just with variability of inter-species vocal communication of all vertebrates in space. Its purpose is to map at which animal species vocalization vary in space. Furthermore, it deals with searching for causes of origin of this variability, such as genetic differences among particular groups of populations, environmental and learning effects etc. within various animal species. In the last part, it tries to answer the question whether the spatial variability of acoustic signals could influence separation of new species and thus have evolutionary consequences.
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