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Allopatric evolution in rousettine fruit bats: from population and landscape genetics to phylogeography
Stříbná, Tereza ; Hulva, Pavel (advisor) ; Bryja, Josef (referee) ; Vallo, Peter (referee)
Population structure, biogeography and phylogenetic relationships of the fruit bat genus Rousettus have been studied in Africa and adjacent regions. The current population patterns of rousettine fruit bats in the Old World are influenced by several environmental attributes, namely the topography, climate and land cover. These variables are mirrored in fruit bat plesiomorphies related to the ecological niche of tropical flying frugivore, as well as apomorphies of rousettines including echolocation ability, roosting in caves and dispersal capacity in open landscapes with discontinuous tree cover. Phylogenetic relationships among species and subspecies of the genus have been indicated and confronted with the existing colonization scenarios. Insular populations (including habitat islands within desert oases) show frequent genetic differentiation from their mainland relatives suggesting successful founder events after traversing stretches of unsuitable habitats. Genetic differentiation evolving in less distant islands suggests involving behavioural mechanisms maintaining cohesion of isolated demes as site fidelity and natal habitat-biased dispersal. In sub-Saharan mainland Africa within the large range reaching from the southern border of Sahara to Cape Peninsula, Rousettus populations share a...
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Social monogamy and parental care in bees of the genus Ceratina
Mikát, Michael ; Straka, Jakub (advisor) ; Bryja, Josef (referee)
Parental care is one of the most successful strategies for providing offspring survival. There are differences in type of care between taxa. There are biparental care, maternal care, paternal care and alloparental care. Bees of the genus Ceratina are suitable model taxon for study of parental care evolution. There is a long time known maternal care and eusociality, in this genus. A species of the genus Ceratina, which has biparental care, is introduced in this thesis. Field experiments were performed from 2011 to 2013 in Podyjí National Park, especially in locality Havraníky heath. Four model species, which are occurring in the Czech Republic, were selected: C. chalybea, C. cucurbitina, C. cyanea and C. nigrolabiata. Artificial nesting opportunities were installed to the field site. Relationship between individuals in nests of C. nigrolabiata was examined by newly developed microsatellite loci. All studied species are solitary in nesting behavior. Their nest structure and nesting phenology is described. Guarding of full brood nest to adulthood of offspring is characteristic behavioral trait for Ceratina bees. This guarding is essential for offspring survival. Experimental nests with removed mother often failed by ant predation, parasitation by chalcid wasp and nest usurpation by other individuals of the...
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Phylogeny of parasitic wasps of Torymidae (Hymenoptera: Chalcidoidea) and evolution of their life-strategies
Janšta, Petr ; Vilímová, Jitka (advisor) ; Bryja, Josef (referee) ; Melika, George (referee)
The thesis is focused on phylogeny of the family Torymidae (Hymenoptera: Chalcidoidea) and evolution of their life-strategies. The study consists of general introduction to the phylogeny and classification of the family Torymidae chapter, four published papers in international journals and one manuscript prepared for submission. Firstly, our aim was to figure out the phylogenetic position of Torymidae as well as the position of other chalcidoid families inside superfamily Chalcidoidea (paper I and II). The supermatrix of sequencies of two ribosomal genes (18S rDNA and 28S rDNA) were developed for 649 species of chalcidoid taxa. However, family Torymidae was considered as polyphyletic group with the subfamily Megastigminae unrelated to the subfamily Toryminae (paper I). Monophyly of Torymidae was corroborated in another study (paper II) focused on molecular and morphological characters. We used a web-based, systematics workbench mx database for scoring 233 characters of 300 members of all chalcidoid families. Contrary to our previous only DNA-based study, we revealed also potential sister relationships of Torymidae with Ormyridae+Colotrechninae or Cerocephalinae+Diparinae respectively. Other paper (paper V) was focused on detailed study of Torymidae phylogeny. A total of 5 genes (18S rDNA, 28S rDNA,...
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Impact of Toll-like receptor 4 polymorphism on pro-inflammatory responsiveness in great tit (Parus major)
Vinklerová, Jitka ; Bryja, Josef (advisor) ; Černý, Jan (referee)
Toll-like receptor 4 (TLR4) belongs among chief bacteria-sensing Pattern recognition receptors. Endotoxin (lipopolysaccharide, LPS) recognition by TLR4 triggers signalling leading to release of cytokines that direct leukocyte infiltration into the inflammatory site and cause swelling. Effector mechanisms that ensure pathogen elimination include phagocytosis and oxidative burst. It has been repeatedly reported that the polymorphism in TLR4 may affect host resistance to various diseases. TLR4 may be, therefore, an important molecule in host-parasite co-evolution. Herein, I focused on TLR4 amino acid substitution Q549R which is associated with ornamentation in great tits. In tits I describe immune responsiveness to LPS stimulation on morphological and molecular level and examine effects of the Q549R substitution on inflammation and general body condition. In LPS- treated individuals I found decrease in heterophil-lymphocyte ratio (H/L) that might be caused by attraction of the blood-borne cells into the inflamed tissue. This is in striking contrast with increase in H/L in PBS-treated animals resulting from the stress response. There was no effect of Q549R on general condition and haematological parameters but I revealed a significant effect of the interaction between host Q549R genotype and the type...
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Hybrid origin of beavers in Central Europe
Albrechtová, Alena ; Munclinger, Pavel (advisor) ; Bryja, Josef (referee)
The aim of the master diploma work is to investigate origin of Czech populations and genetic variability of almost all Eurasian populations of the European beaver (Castor fiber). For our purposes we collected specimens from Czech populations, reintroduced population in Kirov district in Russia and all European and Asian refugia. At the end of the 19th century the species was on the verge of extinction due to overhunting, surviving only in eight isolated refugial areas. The population size at the end of the 19th century was estimated as 1 200 animals. The number of individuals has increased thanks to the legal protection and reintroductions. The current population size is estimated at 640 000. It is obvious that the populations of beaver have recently undergone severe bottleneck. Beaver was completely extirpated in the Czech Republic in the 18th century. Since the 80th of the 20th century beavers re-established in the Czech Republic due to migration from neighbouring countries and reintroduction programmes, however we knew only little about the origin of beavers in the Czech Republic. I showed that our beavers are derived from individuals in France, Germany, Norway and east Europe. Mitochondrial DNA of Castor canadensis has not been found in Czech beavers. I studied microsatellite loci (first use for...
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Genetická struktura mediteránních populací kaloně Rousettus aegyptiacus
Marešová, Tereza ; Hulva, Pavel (advisor) ; Bryja, Josef (referee)
5 Abstract The genus Rousettus represents the only fruit bat genus distributed both in Asia and Africa reaching northern distributional limits of the Pteropodidae family. This unusual distribution pattern is related to the ability of echolocation, subsequent cave dwelling and probably other thermoregulatory and behavioural adaptations to relatively cold and dry climate. Methods for identification of genetically discrete populations were used in the presented study to acquire better comprehension of historical ways of colonization along with current dispersal and migratory patterns of the Egyptian fruit bat (Rousettus aegyptiacus) in the Mediterranean basin and adjacent range patches. Modern approaches to population and landscape genetics were applied on a dataset comprising 553 individuals from 72 localities using 20 nuclear microsatellites. Our results revealed a significant genetic distance of East African individuals and certain substructure in the northern part of the range. Cypriot population is clearly separated, and - for higher K - the isolation of colonies from Egyptian oases is highly supported. Genetic proximity of south Arabian and Sinai populations contradict current taxonomy of the species. Our findings highlight the role of seas and deserts as barriers restricting gene flow and the evolution...
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Regulatory mechanisms of WNT signalling
Pospíchalová, Vendula ; Kořínek, Vladimír (advisor) ; Trka, Jan (referee) ; Bryja, Josef (referee)
AB T mu hom dise β sign mu liga stab tran sign T the focu disc cate of t cell targ the inte con sec I sign BSTRACT The Wnt si lticellular o meostasis. A eases, most β-catenin is nalling). In ltiprotein c ands when t bilized and nscription f nalling is tig This thesis knowledge uses on seq cusses the enin signall the Wnt pa ls of intest geted mous thesis des eraction wit nditional Hi retory cell t In conclusi nalling path T ignalling pa organisms Accordingly notably can s a central m n unstimula complex and they engage d transloca factors and ghtly regula is based on e of the reg quential po positive ro ling outcom athway whic tinal epithe e strains th scribes unp th members ic1 deletion types and en ion, our fin hway in dev athway is o ensuring s y, mutations ncer. mediator of ated cells d degraded e their recep tes to the to drive th ated at vario n four origin gulation of sttranslation ole of nucle me. The third ch reduces lium. Final at enable st ublished da s of the Wn n in the inte nhanced tum ndings contr velopment an one of the m successful s in the pat f canonical W β-catenin d in the pro ptors, degrad nucleus t he transcrip ous levels b nal articles f the Wnt s nal process ear protein d study repo the levels o lly, the las tudying the ata on the nt pathway, estinal epith mourigenesi ributed to t...
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Phylogeny and biogeography of Neotropical and African riverine cichlids: multilocus phylogenetic methods in the evolutionary studies
Musilová, Zuzana ; Novák, Jindřich (advisor) ; Bryja, Josef (referee) ; Reichard, Martin (referee)
Summary: The thesis comprises from the introduction and five main parts: three of them are published papers, the rest two are manuscripts prepared for submitting to the scientific journals. The first two are published phylogenetic studies of the cichlasomatine cichlids based on (1) molecular characters, and (2) both morphological and molecular data with the description of a new genus Andinoacara. The third (3) is the already published description of the new species Andinoacara stalsbergi from Peru combining both morphological and phylogenetic approaches and including the detailed phylogeny of the genus Andinoacara. The next unpublished manuscript (4) is the more detailed comprehensive phylogeography of the two non-relative genera (including Andinoacaras) of the trans-Andean cichlids. Including all valid species from the majority of their distribution areas it was reconstructed the ancestral area of both genera in the Choco region, Colombia, and revealed the directions of their distribution spreading. The last (5) unpublished manuscript is the phylogeographical study of the cichlid genus Serranochromis from the headwaters of the totally unknown Central Angola. It showed several evidences of the faunal exchange among the adjacent river systems. Lastly, the thesis is supplemented by several appendices...
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Alternative reproductive strategies in Common Pochards (Aythya ferina)
Šťovíček, Ondřej ; Albrecht, Tomáš (advisor) ; Bryja, Josef (referee)
Conspecific brood parasitism (CBP) is one of few alternative reproductive strategies exmployed by females. CBP is common in birds because of their mode of reproduction (ovipary), which allows relatively simple dumping own eggs to foreign nest. This strategy is especially common in birds with precocial young, such as waterfowl. In this study, common pochard (Aythya ferina) was the model organism for study of CBP via molecular methods. It is the very first evidence of this kind of parasitism in non-colonial and non-cavity nesting duck species, based on detection of parasitic eggs via microsatellites markers. A set of 17 microsatellites markers (10 of these were newly found and specific for our species) was optimised for detection of rate of parasitism and relatedness between females in whole population. It was found that CBP is surprisingly high in our species, the parasitic eggs (39 % of 252 eggs) were found in 89% of nests. Despite the fact that females preferentially nest near relatives individuals, parasitic females parasitize equally nests nearby and nests in longer distance. However, no preferential parasitism of related individuals was found. Cost of parasitism seems relatively low for both, host and parasite, in our species. This is in accordance with previous finding that common pochard's...
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