Search results for "cyclical parthenogens"

showing 3 items of 3 documents

Daphnia invest in sexual reproduction when its relative costs are reduced

2018

The timing of sex in facultatively sexual organisms is critical to fitness, due to the differing demographic consequences of sexual versus asexual reproduction. In addition to the costs of sex itself, an association of sex with the production of dormant life stages also influences the optimal use of sex, especially in environments where resting eggs are essential to survive unfavourable conditions. Here we document population dynamics and the occurrence of sexual reproduction in natural populations of Daphnia magna across their growing season. The frequency of sexually reproducing females and males increased with population density and with decreasing asexual clutch sizes. The frequency of…

0106 biological sciences0301 basic medicineLIFE-HISTORYsexual reproductioncost of sexAsexual reproductionCYCLICAL PARTHENOGENS01 natural sciencesDaphniaPopulation density2300 General Environmental Sciencetiming of sexLOCAL ADAPTATION2400 General Immunology and Microbiologypopulation dynamicsGeneral Environmental Scienceeducation.field_of_studybiologyINDUCTIONMIXED-EFFECTS MODELSGeneral MedicineCladocera1181 Ecology evolutionary biology590 Animals (Zoology)General Agricultural and Biological SciencesEvolutionPopulationDaphnia magna1100 General Agricultural and Biological SciencesPULEX010603 evolutionary biologyGeneral Biochemistry Genetics and Molecular Biology03 medical and health sciences10127 Institute of Evolutionary Biology and Environmental Studies1300 General Biochemistry Genetics and Molecular BiologyPopulation growtheducationpopulation densityLocal adaptationROTIFERSGeneral Immunology and Microbiologysuvullinen lisääntyminenreproduction (biology)biology.organism_classificationlisääntyminenpopulaatiodynamiikkaSexual reproduction030104 developmental biologyDaphniaMAGNADENSITYvesikirputta1181570 Life sciences; biologyDemography
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Daphnia females adjust sex allocation in response to current sex ratio and density

2018

Cyclical parthenogenesis presents an interesting challenge for the study of sex allocation, as individuals’ allocation decisions involve both the choice between sexual and asexual reproduction, and the choice between sons and daughters. Male production is therefore expected to depend on ecological and evolutionary drivers of overall investment in sex, and those influencing male reproductive value during sexual periods. We manipulated experimental populations, and made repeated observations of natural populations over their growing season, to disentangle effects of population density and the timing of sex from effects of adult sex ratio on sex allocation in cyclically parthenogenetic Daphnia…

Male0106 biological sciencesLIZARDSsukupuolen määräytyminenParthenogenesisDaphnia magna01 natural sciencesPopulation densityLOCAL ADAPTATIONMETAPOPULATIONSex allocationsex allocationeducation.field_of_studyEcologyReproductionINDUCTIONPOPULATION-DENSITYBiological EvolutionCRUSTACEA1181 Ecology evolutionary biology590 Animals (Zoology)FemaleReproductive valueHAPLODIPLOID CYCLICAL PARTHENOGENSsuvuton lisääntyminenSex ratioOffspringcyclical parthenogenCLADOCERAPopulationsex ratio adjustmentBiology010603 evolutionary biology10127 Institute of Evolutionary Biology and Environmental StudiesAnimalsSex Ratioeducationpopulation densityEcology Evolution Behavior and SystematicsLocal adaptationAVAILABILITY010604 marine biology & hydrobiologypartenogeneesipopulaatiodynamiikkaSexual reproduction1105 Ecology Evolution Behavior and SystematicsDaphniaMAGNAvesikirput570 Life sciences; biologyta1181asukastiheysDemographyEcology Letters
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Data from: Adaptation in response to environmental unpredictability

2017

Understanding how organisms adaptively respond to environmental fluctuations is a fundamental question in evolutionary biology. The Mediterranean region typically exhibits levels of environmental unpredictability that vary greatly in habitats over small geographical scales. In cyclically parthenogenetic rotifers, clonal proliferation occurs along with occasional bouts of sex. These bouts contribute to the production of diapausing eggs, which allows survival between growing seasons. Here, we studied two diapause-related traits in rotifers using clones from nine Brachionus plicatilis natural populations that vary in the degree of environmental unpredictability. We tested the hypothesis that t…

medicine and health careBrachionus plicatilisLife SciencesMedicinecyclical parthenogensbet hedgingenvironmental unpredictability
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