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Maternal effect on body size in the Madagascar ground gecko Paroedura picta
Píchová, Veronika ; Starostová, Zuzana (advisor) ; Vrtílek, Milan (referee)
The maternal effect is a phenotypic process in which the mother influences her offspring through her phenotype, her behaviour and also through the environmental condition that affect her. This non-genetic effect can have a variety of manifestations. One way that mothers of oviparous vertebrates can affect their offspring is through the size of their eggs. This thesis aims to investigate whether and how female of the gecko Paroedura picta can influence the growth and final body size of their offspring. Females of this species can reproduce at an early age and increase the size of their eggs during their lifetime. Therefore, I investigated whether this difference in energy allocation to the eggs would affect the size of the hatchlings and subsequently their growth and final body size. The result shows that the eggs mass increases with female body size and larger hatchlings were born from larger eggs. However, smaller hatchlings from smaller eggs grow faster compared to larger ones and exhibit so called compensatory growth. Only the sex affects final body size of an individual, but this effect is not apparent at hatching. In this gecko, the maternal effect is only apparent in the egg size and hatchling size but it does not affect the growth or final body size of an offspring later in the ontogeny.
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Reflection of foster care on a temporary basis by experts
Pichová, Veronika ; Urban, David (advisor) ; Poláčková, Iva (referee)
This bachelor's thesis deals with temporary foster care and reflection of its' contemporary form in practice by experts who operate within the frame work of substitute familial care. The thesis is comprised of theoretical and practical parts. Theoretical part seeks to identify the temporary foster care within legal framework of Czech Republic, its' specifics within substitute familial care and the process of its' realisation. Following chapters of theoretical part describe psychological grounds of the care for endangered children, particularly the needs of children which are met by the institute of temporary foster care. Aspects of coexistence with foster parents and forms of help that could possibly be provided towards children in temporary foster care are a subsequent topic. Practical part deals with the reflection of contemporary charakter of temporary foster care from the perspective of experts who work within the field of substitute familial care. Qualitative research methods applied through semi-structured interview were chosen to meet the demands of this thesis. Research goal of this thesis is the identification of positive and negative aspects of implementation of temporary foster care.
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Energetic costs of tail autotomy and regeneration in reptiles
Píchová, Veronika ; Starostová, Zuzana (advisor) ; Frýdlová, Petra (referee)
Most reptile species have the ability to voluntarily cast off their tail, known as autotomy, followed by tail regeneration, which is used as an antipredatory mechanism. In spite of this being a successful ecological adaptation, the individual with its tail cast off is often influenced negatively, which includes increased probability of predation, lower locomotion capabilities, lower immunity or a change in its social standing. Last but not least, casting off the tail and the following regeneration may distinctively influence the energy of the individual, either directly through the loss of fat reserve, usually located in the tail itself, or because the regeneration of lost tissue demands a lot of energy and often requires relocation of energy at the expense of other processes. Autotomy and regeneration of the tail may thus influence important traits of physiological processes such as body growth or body mass, reproductive capabilities or metabolism intensity. The influence of autotomy on these aspects of an individual's life has been a studies topic in the last few years, but conclusions vary. The goal of this thesis is a brief summary of information about the mechanism of caudal autotomy and regeneration and also summarize contemporary knowledge about energy costs connected to autotomy and...
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