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Reproductive isolation barriers in the hybrid zone of the house mouse (Mus musculus)
Albrechtová, Jana ; Piálek, Jaroslav (advisor) ; Sedláček, František (referee) ; Reifová, Radka (referee)
Reproductive isolation occurring at the gamete level is called gametic isolation and almost always prevents gene flow between unrelated species and (to some extent) between closely related species or subspecies. The hybrid zone of the house mouse (HMHZ), which was formed by contact and interbreeding of two subspecies, the Western European house mouse (M. m. domesticus) and the Eastern European house mouse (M. m. musculus) provides a usefull model for the study of speciation processes involving gametic isolation. The probability of sperm competition within the female reproductive tract is high in the house mouse because high levels of sexual promiscuity (in 20˗40 % of all reproductive cycles) have been observed in this species. Thus, the reproductive isolation at gametic level may be determined both by the phenotypic characteristics of sperm (the ability to outcompete heterospecific sperm in the process of sperm- sperm competition) and by the preference of the sperm of conspecific males in the female reproductive tract (cryptic female choice). In my Ph.D. thesis I tested the degree of affinity of male and female gametes reciprocally between the both subspecies of M. musculus and the phylogenetically more distant species M. spretus, which is characterized by a higher degree of promiscuity. Although a...
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Behavioural and genetic study of premating isolation in the house mouse hybrid zone
Bímová, Barbora ; Piálek, Jaroslav (advisor) ; Šumbera, Radim (referee) ; Burda, Hynek (referee)
SUMMÁRY oF. Ph.D.THESIS Behaviouralisolation includes all differencesin courtshipbehaviourthat allow the recognitionand successf,rlmating only within membersof the same species and therewithreducethe probability of maladaptivehybridization.It can be an efficient barrier to gene flow betweenclosely related taxa and contributeto or potentially completetheirspeciation.An idealopportunityto studytheroleofbehaviouralisolation duringthespeciationprocessrepresentcloselyrelatedor recentlydivergingtax4 where theexchangeofgenes still occursandtheprocessofspeciationwas not achieved.The housemousecan be seenas a uniquemodel to addressspeciationgeneticquestions. This speciesis a greatlaboratoryanimalwith describedgenomesequencein one side andwiththenaturalhybridzonesbetweendifferentmousesubspeciesontheotherhand. In my thesisI studiedthe role of assortativematingleadingto behaviouralisolation betweentwo subspeciesof the house mouse Mzs musculusmusculus utd M. m. domesticusin both naturalpopulationsliom the Czech-Bavariantransectacrosstheir hybridzoneas well as in thelaboratory,usingwild-derivedinbredstrainsrepresenting bothsubspecies. I foundthatthereis a strongdivergencein boththe signalandpreferencepartsof the subspecies-specificrecognitionsystembetweenthetwo subspecies.I analysedtherole ofsalivary...
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Behavioural and genetic study of premating isolation in the house mouse hybrid zone
Bímová, Barbora ; Piálek, Jaroslav (advisor) ; Šumbera, Radim (referee) ; Burda, Hynek (referee)
SUMMÁRY oF. Ph.D.THESIS Behaviouralisolation includes all differencesin courtshipbehaviourthat allow the recognitionand successf,rlmating only within membersof the same species and therewithreducethe probability of maladaptivehybridization.It can be an efficient barrier to gene flow betweenclosely related taxa and contributeto or potentially completetheirspeciation.An idealopportunityto studytheroleofbehaviouralisolation duringthespeciationprocessrepresentcloselyrelatedor recentlydivergingtax4 where theexchangeofgenes still occursandtheprocessofspeciationwas not achieved.The housemousecan be seenas a uniquemodel to addressspeciationgeneticquestions. This speciesis a greatlaboratoryanimalwith describedgenomesequencein one side andwiththenaturalhybridzonesbetweendifferentmousesubspeciesontheotherhand. In my thesisI studiedthe role of assortativematingleadingto behaviouralisolation betweentwo subspeciesof the house mouse Mzs musculusmusculus utd M. m. domesticusin both naturalpopulationsliom the Czech-Bavariantransectacrosstheir hybridzoneas well as in thelaboratory,usingwild-derivedinbredstrainsrepresenting bothsubspecies. I foundthatthereis a strongdivergencein boththe signalandpreferencepartsof the subspecies-specificrecognitionsystembetweenthetwo subspecies.I analysedtherole ofsalivary...
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Sperm morphology in the secondary contact zone of Common Nightingale and Thrush Nightingale
Opletalová, Kamila ; Reifová, Radka (advisor) ; Piálek, Jaroslav (referee)
The male gametes (sperms) are under strong sexual selection and are therefore very diverse in their morphology and often differ even amongst closely related species. Sperms are thus assumed to play very important role in reproductive isolation between species, due to their fast evolution in morphology. In my master thesis, I have studied the possible role of sperm morphology divergence in reproductive isolation in two sister species of passerine birds, the common nightingale (Luscinia megarhynchos) and the thrush nightingale (L. luscinia). The areas of these species overlap in secondary contact zone running across central and Eastern Europe, where they occasionally hybridize. I have compared sperm morphology of males of both species originating in allopatric and sympatric localities as well as interspecies hybrids. The results showed significant differences in total sperm length which is approximately 20 % longer in the common nightingale. That is caused by great interspecies divergence in midpiece (containing mitochondria) length. Interspecific hybrids showed sperms with intermediate length but despite expectations completely morphologically normal. This outcome corresponds with observed fertility in F1 hybrid males. What I consider to be an essential finding is a significant divergence in head...
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Study of chemical communication in the house mouse: a proteomic approach
Janotová, Kateřina ; Stopka, Pavel (advisor) ; Piálek, Jaroslav (referee) ; Vošlajerová, Barbora (referee)
Chemical communication of the house mouse is similarly as in other mammals, substantially complex and influence every social ineraction between individuals. Important part of mouse chemical signalling system is Major Urinary Protein complex (MUP). These proteins are known as pheromone-carriers that prolong longevity of the pheromones by retarding their evaporation from the scent mark. Their other role in chemical communication is direct signalling which is mediated by VNO. MUP have been shown to trigger both behavioural and physiological effects in recipient. Proteins belonging to the same family (lipocalins) as MUPs, have been found in other, mainly rodent, species. Although the information about these urinary lipocalins are, with exception of mouse, very limited, it is likely that their roles relies in chemical communication. The Ph.D. thesis is related to the urinary proteins in the house mouse and Mastomys coucha. Thesis contains four chapters represented by three published and one submitted manuscript. One aim of the thesis is to provide information about these proteins in the subspecies Mus musculus musculus which is widespread in the Czech Republic and which is much less studied when compared to Mus musculus domesticus. The part of Ph.D thesis is a review publication which summarizes recent...
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