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How evolution of coloration in parrots (Psittaciformes) affects species conservation through human preferences
Lišková, Silvie ; Frynta, Daniel (advisor) ; Šumbera, Radim (referee)
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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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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Effects of melanin-based coloration and commensalism on performance in behavioural tests: a comparative study
Kahounová, Hana ; Frynta, Daniel (advisor) ; Šumbera, Radim (referee)
An intraspecific coat colour polymorphism exists in the genus Acomys. Some populations are dark and others are light-colored. Dark populations live in lava deserts, savannas and in the commensal habitat of Egypt. The subject of this thesis is to compare selected populations of Acomys in behavioral test of forced exploration. They are dark commensal, light secondary non-commensal, light non- commensal, and one dark non-commensal populations. The aim of this research is to find out whether the dark commensal populations of Acomys cahirinus differ in behavior from other populations and whether dark populations differ in behavior from light populations. According to the results, the observed behavioral parameters do not show significant differences between populations. The dark commensal populations of A. cahirinus did not differ significantly from other populations in exploratory behavior. But the dark populations preferred a dark background. No apparent differences in behavior between differently colored populations were found. However, the variability in tested behavior between populations was found. Key words: exploratory behavior, melanin, commensalism, comparative approach, open field test, Acomys
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Maternal investment and reproductive strategy in domestic horses
Komárková, Martina ; Bartošová, Jitka (advisor) ; Šumbera, Radim (referee) ; Vlček, Kamil (referee)
The aim of my doctoral thesis is the detailed study of the behavioural and sociobiological principles associated with the period of lactation. Suckling data covering almost 80 foals of domestic horse (Equus caballus) was obtained within four years of observation in the National Stud in Kladruby nad Labem, Czech Republic. The data were evaluated together with the reproductive history of the mothers, their agonistic interactions and following analysis of the dominance position of subadult foals. The first study describes longer suckling (greater maternal care) in dominant mares compared to submissive ones. Dominant mares are also less disturbed during nursing, whereas they terminated the nursing of submissive mares more often. A possible competitive advantage for the offspring of dominant mares may arise from such behaviour. The second paper enlightens the reproductive strategy of mares facing double maternal investment; suckling of the foal and pregnancy at the same time. I found out, contrary to the expectations, that the pregnant mares neither suckled their foals less nor terminated more suckling compared to non-pregnant herdmates. They may try to compensate their suckling foal with the perspective of its early weaning due to ongoing pregnancy. In the third and fourth manuscript I studied, how...
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Strategie mateřské investice u modelového monotokního a polytokního savce z pohledu životní historie
Dušek, Adam ; Stopka, Pavel (advisor) ; Šumbera, Radim (referee) ; Tkadlec, Emil (referee)
The litter size is one of the most important determinants of mammalian life-histories. Depending on the size of the litter, the mammals can be divided into two main groups: (1) the monotocous mammals, producing only one offspring per litter; and (2) the polytocous mammals, producing more than one offspring per litter. This life-history dichotomy entails different strategies whereby the mammalian females may optimize their maternal investment. The aim of this Ph.D. thesis is to show variation in the maternal investment strategies of monotocous and polytocous mammals from a life-history perspective. In order to address this issue, I investigated the strategy of maternal investment in the red deer (Cervus elaphus), representing a typical monotocous mammal, and the house mouse (Mus musculus), representing a typical polytocous mammal. From a life-history perspective, the red deer, producing no more than one litter per year, can be viewed as a model of "K-selected species", while the house mouse, producing up to ten litters per year, can be viewed as a model of "r- selected species". The red deer and the house mouse are ideal model organisms for this type of research also because they both are representatives of the most common mammalian mating system - the simultaneous polygyny. A general assumption of...
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