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The effects of mating with multiple males on reproductive success of a female: An experimental study in leopard gecko (Eublepharis macularius)
Ševčíková, Pavlína ; Frynta, Daniel (advisor) ; Rehák, Ivan (referee)
The aim of the project was to test female advantages of promiscuous and/or polyandrous mating. Although, previous studies reported improved reproductive success of females copulating with multiple males in many model species, including Eublepharis macularius, this study failed to demonstrate such a benefit of polyandry. Traits reflecting female reproductive success, i.e. the number of produced eggs, egg mass, hatchability, hatchling mass, growth and survival were not influenced by copulation with multiple partners, but some of them were dependent on female condition. Only initial stages of juvenile growth were influenced by female identity and/or investment.
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The effect of social factors on reproduction and stress in spiny mouse (Acomys cahirinus)
Fraňková, Marcela ; Frynta, Daniel (advisor) ; Pavelková Ricanková, Věra (referee) ; Valeš, Karel (referee)
1 Summary This thesis deals with relationships among social factors, behaviour, physiology and reproduction in spiny mouse (Acomys cahirinus). Spiny mice are social rodents with that should be kept in families consisting of an adult male, multiple females and their descendants which mimic their wild social system. In contrast to many other muroid rodents, spiny mice produce after an extended gestation period only small litters consisting of relatively large and well developed (precocoial) newborns. The first part of the thesis is focused on effects of selected social parameters on glucocorticoid levels, which are widely used as a marker of stress. We focused on non-invasive monitoring of glucocorticoid metabolites (GCM) in faeces via enzyme immunoassay. For this purpose two specific antibodies were validated via an ACTH challenge test. Further, we constructed a special experimental apparatus which allowed us routine repeated collection of faecal samples in socially living rodents without noticeable disturbance to studied animals. Next, we monitored baseline concentrations of faecal GCM levels of individuals in family groups of commensal and non-commensal population. We found no effect of age (i.e., social dominance) and only a small effect of sex (in the commensal population only, with males exhibiting...
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Social organisation in nocturnal primates
Papoušková, Monika ; Frynta, Daniel (advisor) ; Stopková, Romana (referee)
Noční primáti byli dlouho popisováni jako samotářští, bez sociálních vztahů a s minimem přímého kontaktu mimo dobu páření. Byli nahlíženi jako homogenní skupina s uniformní a primitivní sociální organizací. Většina těchto primátů si sice hledá potravu o samotě, studie z poslední doby však ukazují, že řada druhů nočních primátů sociální je. Vytvářejí sítě sociálních vztahů a škála sociálních projevů se příliš neliší od té, kterou známe u denních primátů. Navíc zde existuje velká diverzita a variabilita mezi druhy. Tato práce shrnuje dosavadní poznatky o sociální organizaci u nočních primátů, věnuje se historii jejího výzkumu a také evolučním vlivům, které mohou na socialitu u nočních primátů působit. Klíčová slova: sociální organizace; noční primáti; Tarsius; radio-telemetrie, sociální chování ABSTRACT Nocturnal primates have been described as solitary, without social networks and with minimum direct contact outside the mating season. They have been perceived as a homogenous group with uniform and primitive social organisation. Most of these primates forage solitarily, however recent studies have shown that a substantial number of nocturnal primate species is social. They possess social networks and the scale of their social interactions does not differ much from the one we know in diurnal primates....
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How evolution of coloration in parrots (Psittaciformes) affects species conservation through human preferences
Lišková, Silvie ; Šumbera, Radim (referee) ; Frynta, Daniel (advisor)
Each year, several new species are recognized as threatened or endangered. Today's worldwide zoos and aquariums are highly concerned in their conservation and the species kept in large numbers have high chances for possible future reintroduction. However, the selection of the species kept is decided by men and as such can be affected by human aesthetic preferences. The aim of this thesis was to test the hypothesis that zoos preferentially keep species that are attractive rather than endangered, using the parrot family (Psittaciformes) as an example. We collected data from 460 human respondents who evaluated the attractiveness of parrots presented on painted illustrations. After analyzing which traits affect the perceived beauty we found that humans prefer parrots that are big, long-tailed and colourful (blue, orange and yellow). There was a considerable agreement among the respondents. We repeatedly confirmed significant positive association between the perceived beauty and the size of worldwide zoo population. In addition of perceived beauty, area of distribution and body size appeared significant predictors of zoo population size. In contrast, the effects of conservation status and taxonomic uniqueness appeared insignificant. Our results suggest that zoos preferentially keep beautiful parrots and pay less...
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