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  • 4151.
    Zhou, Yongqiang
    et al.
    Chinese Acad Sci, Nanjing Inst Geog & Limnol, Taihu Lab Lake Ecosyst Res, State Key Lab Lake Sci & Environm, Nanjing 210008, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Yu, Xiaoqin
    Chinese Acad Sci, Nanjing Inst Geog & Limnol, Taihu Lab Lake Ecosyst Res, State Key Lab Lake Sci & Environm, Nanjing 210008, Peoples R China.;Luoshe Senior High Sch, Wuxi 214000, Jiangsu, Peoples R China..
    Zhou, Lei
    Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, 71 East Beijing Rd, Nanjing 210008, Peoples R China..
    Zhang, Yunlin
    Chinese Acad Sci, Nanjing Inst Geog & Limnol, Taihu Lab Lake Ecosyst Res, State Key Lab Lake Sci & Environm, Nanjing 210008, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Xu, Hai
    Chinese Acad Sci, Nanjing Inst Geog & Limnol, Taihu Lab Lake Ecosyst Res, State Key Lab Lake Sci & Environm, Nanjing 210008, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Zhu, Mengyuan
    Chinese Acad Sci, Nanjing Inst Geog & Limnol, Taihu Lab Lake Ecosyst Res, State Key Lab Lake Sci & Environm, Nanjing 210008, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Zhu, Guangwei
    Chinese Acad Sci, Nanjing Inst Geog & Limnol, Taihu Lab Lake Ecosyst Res, State Key Lab Lake Sci & Environm, Nanjing 210008, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Jang, Kyoung-Soon
    Korea Basic Sci Inst, Biochem Anal Grp, Cheongju 28119, South Korea..
    Spencer, Robert G. M.
    Florida State Univ, Dept Earth Ocean & Atmospher Sci, Tallahassee, FL 32306 USA..
    Jeppesen, Erik
    Aarhus Univ, Dept Ecosci, CF Mollers Alle 3, DK-8000 Aarhus, Denmark.;Aarhus Univ, Ctr Water Technol WATEC, CF Mollers Alle 3, DK-8000 Aarhus, Denmark.;Sino Danish Ctr Educ & Res, Beijing 100190, Peoples R China.;Middle East Tech Univ, Limnol Lab, Dept Biol Sci, TR-06800 Ankara, Turkey.;Middle East Tech Univ, Ctr Ecosyst Res & Implementat, TR-06800 Ankara, Turkey.;Middle East Tech Univ, Inst Marine Sci, TR-33731 Mersin, Turkey..
    Brookes, Justin D.
    Univ Adelaide, Water Res Ctr, Sch Biol Sci, Adelaide, SA 5005, Australia..
    Kothawala, Dolly
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology. Uppsala Univ, Dept Ecol & Genet Limnol, S-75236 Uppsala, Sweden..
    Wu, Fengchang
    Chinese Res Inst Environm Sci, State Key Lab Environm Criteria & Risk Assessment, Beijing 100012, Peoples R China..
    Rainstorms drive export of aromatic and concurrent bio-labile organic matter to a large eutrophic lake and its major tributaries2023In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 229, article id 119448Article in journal (Refereed)
    Abstract [en]

    Lakes are hotspots for global carbon cycling, yet few studies have explored how rainstorms alter the flux, composition, and bio-lability of dissolved organic matter (DOM) in inflowing rivers using high-frequency monitoring. We conducted extensive campaigns in the watershed of Lake Taihu and made daily observations for three years in its two largest inflowing tributaries, River Dapu and River Yincun. We found higher DOC, bio-labile DOC (BDOC), and specific UV absorbance (SUVA(254)) levels in the northwestern inflowing regions compared with the remaining lake regions. DOC and BDOC increased during rainstorms in River Dapu, and DOC declined due to local dilution and BDOC increased during rainstorms in River Yincun. We found that rainstorms resulted in increased DOM absorbance a(350), SUVA(254), and humification index (HIX) and enhanced percentages of humic-like fluorescent components, %polycyclic condensed aromatic and %polyphenolic compounds as revealed from ultrahigh-resolution mass spectrometry (FT-ICR MS), while spectral slope (S275-295) and the percentages of protein-like C1 and C3 declined during rainstorms compared with other seasons. This can be explained by a combined flushing of catchment soil organic matter and household effluents. The annual inflows of DOC and BDOC to Lake Taihu were 1.15 +/- 0.18 x 10(4) t C yr(-1) and 0.23 +/- 0.06 x 104 t C yr(-1) from River Dapu and 2.92 +/- 0.42 x 103 t C yr(-1) and 0.53 +/- 0.07 x 10(3) t C yr(-1) from River Yincun, respectively, and the fluxes of DOC and BDOC from both rivers increased during rainstorms. We found an elevated frequency of heavy rainfall and rainstorms in the lake watershed during the past six decades. We conclude that an elevated input of terrestrial organic-rich DOM with concurrent high aromaticity and high bio-lability from inflowing rivers is likely to occur in a future wetter climate.

  • 4152.
    Zhou, Yongqiang
    et al.
    Chinese Acad Sci, Taihu Lab Lake Ecosyst Res, State Key Lab Lake Sci & Environm, Nanjing Inst Geog & Limnol, Nanjing 210008, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Zhou, Lei
    Chinese Acad Sci, Inst Soil Sci, State Key Lab Soil & Sustainable Agr, Nanjing 210008, Peoples R China..
    Zhang, Yunlin
    Chinese Acad Sci, Taihu Lab Lake Ecosyst Res, State Key Lab Lake Sci & Environm, Nanjing Inst Geog & Limnol, Nanjing 210008, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Zhu, Guangwei
    Chinese Acad Sci, Taihu Lab Lake Ecosyst Res, State Key Lab Lake Sci & Environm, Nanjing Inst Geog & Limnol, Nanjing 210008, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Qin, Boqiang
    Chinese Acad Sci, Taihu Lab Lake Ecosyst Res, State Key Lab Lake Sci & Environm, Nanjing Inst Geog & Limnol, Nanjing 210008, Peoples R China.;Univ Chinese Acad Sci, Beijing 100049, Peoples R China..
    Jang, Kyoung-Soon
    Korea Basic Sci Inst, Biochem Anal Grp, Cheongju 28119, South Korea..
    Spencer, Robert G. M.
    Florida State Univ, Dept Earth Ocean & Atmospher Sci, Tallahassee, FL 32306 USA..
    Kothawala, Dolly
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Jeppesen, Erik
    Aarhus Univ, Dept Biosci, DK-8600 Silkeborg, Denmark.;Aarhus Univ, Ctr Water Technol WATEC, DK-8600 Silkeborg, Denmark.;Danish Ctr Educ & Res, Beijing 100190, Peoples R China.;Middle East Tech Univ, Dept Biol Sci, Limnol Lab, TR-06800 Ankara, Turkey.;Middle East Tech Univ, Ctr Ecosyst Res & Implementat, TR-06800 Ankara, Turkey.;Middle East Tech Univ, Inst Marine Sci, TR-33731 Mersin, Turkey..
    Brookes, Justin D.
    Univ Adelaide, Water Res Ctr, Sch Biol Sci, Adelaide, SA 5005, Australia..
    Wu, Fengchang
    Chinese Res Inst Environm Sci, State Key Lab Environm Criteria & Risk Assessment, Beijing 100012, Peoples R China..
    Unraveling the Role of Anthropogenic and Natural Drivers in Shaping the Molecular Composition and Biolability of Dissolved Organic Matter in Non-pristine Lakes2022In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 56, no 7, p. 4655-4664Article in journal (Refereed)
    Abstract [en]

    Lakes receive and actively process terrestrial dissolved organic matter (DOM) and play an important role in the global carbon cycle. Urbanization results in elevated inputs of nonpoint-source DOM to headwater streams. Retention of water in lakes allows time for alteration and transformation of the chemical composition of DOM by microbes and UV radiation. Yet, it remains unclear how anthropogenic and natural drivers impact the composition and biolability of DOM in non-pristine lakes. We used optical spectroscopy, Fourier transform ion cyclotron mass spectrometry, stable isotopic measurements, and laboratory bioincubations to investigate the chemical composition and biolability of DOM across two large data sets of lakes associated with a large gradient of urbanization in lowland Eastern China, encompassing a total of 99 lakes. We found that increased urban land use, gross domestic products, and population density in the catchment were associated with an elevated trophic level index, higher chlorophyll-a, higher bacterial abundance, and a higher amount of organic carbon with proportionally higher contribution of aliphatic and peptide-like DOM fractions, which can be highly biolabile. Catchment areas, water depth, lake area: catchment area, gross primary productivity, delta O-18-H2O, and bacterial abundance, however, had comparatively little linkage with DOM composition and biolability. Urban land use is currently intensifying in many developing countries, and our results anticipate an increase in the level of biolabile aliphatic DOM from nonpoint sources and accelerated carbon cycling in lake ecosystems in such regions.

  • 4153.
    Zhu, Shanshan
    et al.
    Zhejiang Univ, Coll Life Sci, MOE Lab Biosyst Homeostasis & Protect, Systemat & Evolutionary Bot & Biodivers Grp, Hangzhou 310058, Zhejiang, Peoples R China..
    Chen, Jun
    Zhejiang Univ, Coll Life Sci, MOE Lab Biosyst Homeostasis & Protect, Systemat & Evolutionary Bot & Biodivers Grp, Hangzhou 310058, Zhejiang, Peoples R China..
    Zhao, Jing
    Novogene Bioinformat Inst, Beijing 100083, Peoples R China..
    Comes, Hans Peter
    Salzburg Univ, Dept Biosci, A-5020 Salzburg, Austria..
    Li, Pan
    Zhejiang Univ, Coll Life Sci, MOE Lab Biosyst Homeostasis & Protect, Systemat & Evolutionary Bot & Biodivers Grp, Hangzhou 310058, Zhejiang, Peoples R China..
    Fu, Chengxin
    Zhejiang Univ, Coll Life Sci, MOE Lab Biosyst Homeostasis & Protect, Systemat & Evolutionary Bot & Biodivers Grp, Hangzhou 310058, Zhejiang, Peoples R China..
    Xie, Xiao
    Ningbo Univ, Sch Marine Sci, Ningbo 315211, Zhejiang, Peoples R China..
    Lu, Ruisen
    Zhejiang Univ, Coll Life Sci, MOE Lab Biosyst Homeostasis & Protect, Systemat & Evolutionary Bot & Biodivers Grp, Hangzhou 310058, Zhejiang, Peoples R China..
    Xu, Wuqin
    Zhejiang Univ, Coll Life Sci, MOE Lab Biosyst Homeostasis & Protect, Systemat & Evolutionary Bot & Biodivers Grp, Hangzhou 310058, Zhejiang, Peoples R China..
    Feng, Yu
    Zhejiang Univ, Coll Life Sci, MOE Lab Biosyst Homeostasis & Protect, Systemat & Evolutionary Bot & Biodivers Grp, Hangzhou 310058, Zhejiang, Peoples R China..
    Ye, Wenqing
    Zhejiang Univ, Coll Life Sci, MOE Lab Biosyst Homeostasis & Protect, Systemat & Evolutionary Bot & Biodivers Grp, Hangzhou 310058, Zhejiang, Peoples R China..
    Sakaguchi, Shota
    Kyoto Univ, Grad Sch Human & Environm Studies, Sakyo Ku, Yoshida Nihonmatsu Cho, Kyoto 6068501, Japan..
    Isagi, Yuji
    Kyoto Univ, Grad Sch Agr, Sakyo Ku, Kitashirakawa Oiwake Cho, Kyoto 6068501, Japan..
    Li, Linfeng
    Fudan Univ, Sch Life Sci, Key Lab Biodivers Sci & Ecol Engn, Minist Educ, Shanghai 200433, Peoples R China..
    Lascoux, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Qiu, Yingxiong
    Zhejiang Univ, Coll Life Sci, MOE Lab Biosyst Homeostasis & Protect, Systemat & Evolutionary Bot & Biodivers Grp, Hangzhou 310058, Zhejiang, Peoples R China..
    Genomic insights on the contribution of balancing selection and local adaptation to the long-term survival of a widespread living fossil tree,Cercidiphyllum japonicum2020In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 228, no 5, p. 1674-1689Article in journal (Refereed)
    Abstract [en]

    'Living fossils' are testimonies of long-term sustained ecological success, but how demographic history and natural selection contributed to their survival, resilience, and persistence in the face of Quaternary climate fluctuations remains unclear. To better understand the interplay between demographic history and selection in shaping genomic diversity and evolution of such organisms, we assembled the whole genome ofCercidiphyllum japonicum, a widespread East Asian Tertiary relict tree, and resequenced 99 individuals ofC. japonicumand its sister species,Cercidiphyllum magnificum(Central Japan). We dated this speciation event to the mid-Miocene, and the intraspecific lineage divergence ofC. japonicum(China vs Japan) to the Early Pliocene. Throughout climatic upheavals of the late Tertiary/Quaternary, population bottlenecks greatly reduced the genetic diversity ofC. japonicum. However, this polymorphism loss was likely counteracted by, first, long-term balancing selection at multiple chromosomal and heterozygous gene regions, potentially reflecting overdominance, and, second, selective sweeps at stress response and growth-related genes likely involved in local adaptation. Our findings contribute to a better understanding of how living fossils have survived climatic upheaval and maintained an extensive geographic range; that is, both types of selection could be major factors contributing to the species' survival, resilience, and persistence.

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  • 4154.
    Zhu, Yishu
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Exploring speciation: postzygotic isolation and mitonuclear dysfunction under divergent climate adaptation2022Report (Other academic)
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  • 4155.
    Zielinski, P.
    et al.
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Nadachowska-Brzyska, Krystyna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Dudek, K.
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Babik, W.
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Divergence history of the Carpathian and smooth newts modelled in space and time2016In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 25, no 16, p. 3912-3928Article in journal (Refereed)
    Abstract [en]

    Information about demographic history is essential for the understanding of the processes of divergence and speciation. Patterns of genetic variation within and between closely related species provide insights into the history of their interactions. Here, we investigated historical demography and genetic exchange between the Carpathian (Lissaritan montandoni, Lm) and smooth (L. vulgaris, Lv) newts. We combine an extensive geographical sampling and multilocus nuclear sequence data with the approximate Bayesian computation framework to test alternative scenarios of divergence and reconstruct the temporal and spatial pattern of gene flow between species. A model of recent (last glacial period) interspecific gene flow was favoured over alternative models. Thus, despite the relatively old divergence (4-6 mya) and presumably long periods of isolation, the species have retained the ability to exchange genes. Nevertheless, the low migration rates (ca. 10 per gene copy per generation) are consistent with strong reproductive isolation between the species. Models allowing demographic changes were favoured, suggesting that the effective population sizes of both species at least doubled as divergence reaching the current ca. 0.2 million in Lm and 1 million in Lv. We found asymmetry in rates of interspecific gene flow between Lm and one evolutionary lineage of Lv. We suggest that intraspecific polymorphism for hybrid incompatibilities segregating within Lv could explain this pattern and propose further tests to distinguish between alternative explanations. Our study highlights the importance of incorporating intraspecific genetic structure into the models investigating the history of divergence.

  • 4156. Zielinski, P.
    et al.
    Nadachowska-Brzyska, Krystyna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Wielstra, B.
    Szkotak, R.
    Covaciu-Marcov, S. D.
    Cogalniceanu, D.
    Babik, W.
    No evidence for nuclear introgression despite complete mtDNA replacement in the Carpathian newt (Lissotriton montandoni)2013In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 22, no 7, p. 1884-1903Article in journal (Refereed)
    Abstract [en]

    Patterns of interspecific introgression may vary geographically, and the distribution of introgressed variants can yield insight into the historical dynamics of genetic interactions between hybridizing species. Urodele amphibians, often characterized by limited mobility, deep intraspecific genetic structuring and vulnerability to climatic changes, constitute suitable models for such historical inferences. Here, we combine an extensive survey of the mitochondrial (mtDNA) and nuclear (15 microsatellites) genomes in the Carpathian newt, Lissotriton montandoni (Lm) with species distribution modelling (SDM). Populations of the smooth newt, L.vulgaris (Lv) from the areas surrounding the Lm range were also sampled to test whether gene flow between these hybridizing species extends beyond the area of strict syntopy. The extent of introgression differs dramatically between the mitochondrial genome and the nuclear genome. While multiple, spatially and temporally distinct introgression events from Lv resulted in complete mtDNA replacement in Lm, there was little evidence of recent interspecific nuclear gene flow in the assayed markers. Microsatellite differentiation within Lm defines three units, probably derived from separate glacial refugia, located in the northern, eastern and southern part of the Carpathians. In situ survival and range fragmentation of Lm are supported by SDM, corroborating the role of the Carpathians as a major refugial area. Our results, in combination with previous reports of extensive introgression of the major histocompatibility complex (MHC) genes, emphasize the complexity of historical gene exchange between Lm and Lv.

  • 4157.
    Zieminska, Kasia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Research Institute for Development, Botany and Modeling of Plant Architecture and Vegetation (AMAP) Montpellier France.
    Bibbo, Silvia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Farrar, Samuel L.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Thompson, Jill
    UK Centre for Ecology & Hydrology Bush Estate Penicuik UK.
    Uriarte, María
    Ecology, Evolution and Environmental Biology Columbia University New York New York USA.
    Ziaco, Emanuele
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Department of Geography Johannes Gutenberg University Mainz Germany.
    Zimmerman, Jess K.
    Department of Environmental Science University of Puerto Rico San Juan Puerto Rico USA.
    Muscarella, Robert
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Shifts in wood anatomical traits after a major hurricane2023In: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 37, no 12, p. 3000-3014Article in journal (Refereed)
    Abstract [en]

    1. Trait variation across individuals and species influences the resistance and resilience of ecosystems to disturbance, and the ability of individuals to capitalize on postdisturbance conditions. In trees, the anatomical structure of xylem directly affects plant function and, consequently, it is a valuable lens through which to understand resistance and resilience to disturbance.

    2. To determine how hurricanes affect wood anatomy of tropical trees, we characterized a set of anatomical traits in wood produced before and after a major hurricane for 65 individuals of 10 Puerto Rican tree species. We quantified variation at different scales (among and within species, and within individuals) and determined trait shifts between the pre- and posthurricane periods. We also assessed correlations between traits and growth rates.

    3. While the majority of anatomical trait variation occurred among species, we also observed substantial variation within species and individuals. Within individuals, we found significant shifts for some traits that generally reflected increased hydraulic conductivity in the posthurricane period. We found weak evidence for an association between individual xylem anatomical traits and diameter growth rates.

    4. Ultimately, within-individual variation of xylem anatomical traits observed in our study could be related to posthurricane recovery and overall growth (e.g. canopy filling). Other factors, however, likely decouple a relationship between xylem anatomy and diameter growth. While adjustments of wood anatomy may enable individual trees to capitalize on favourable postdisturbance conditions, these may also influence their future responses or vulnerability to subsequent disturbances.

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  • 4158.
    Zieminska, Kasia
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Arnold Arboretum Harvard Univ, Boston, MA 02115 USA.
    Rosa, Emily
    Sonoma State Univ, Dept Biol, Rohnert Pk, CA 94928 USA..
    Gleason, Sean M.
    ARS, USDA, Water Management & Syst Res Unit, Ft Collins, CO USA..
    Holbrook, N. Michele
    Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA..
    Wood day capacitance is related to water content, wood density, and anatomy across 30 temperate tree species2020In: Plant, Cell and Environment, ISSN 0140-7791, E-ISSN 1365-3040, Vol. 43, no 12, p. 3048-3067Article in journal (Refereed)
    Abstract [en]

    Water released from wood during transpiration (capacitance) can meaningfully affect daily water use and drought response. To provide context for better understanding of capacitance mechanisms, we investigated links between capacitance and wood anatomy. On twigs of 30 temperate angiosperm tree species, we measured day capacitance (between predawn and midday), water content, wood density, and anatomical traits, that is, vessel dimensions, tissue fractions, and vessel-tissue contact fractions (fraction of vessel circumference in contact with other tissues). Across all species, wood density (WD) and predawn lumen volumetric water content (VWCL-pd) together were the strongest predictors of day capacitance (r(adj)(2)= .44). Vessel-tissue contact fractions explained an additional similar to 10% of the variation in day capacitance. Regression models were not improved by including tissue lumen fractions. Among diffuse-porous species, VWCL-pd and vessel-ray contact fraction together were the best predictors of day capacitance, whereas among semi/ring-porous species, VWCL-pd, WD and vessel-fibre contact fraction were the best predictors. At predawn, wood was less than fully saturated for all species (lumen relative water content = 0.52 +/- 0.17). Our findings imply that day capacitance depends on the amount of stored water, tissue connectivity and the bulk wood properties arising from WD (e.g., elasticity), rather than the fraction of any particular tissue.

  • 4159.
    Zink, Eren
    et al.
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Department of Cultural Anthropology and Ethnology.
    Elvander, Marianne
    Lindberg, Ann
    Järhult, Josef D.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Infectious Diseases. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Målqvist, Mats
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Women's and Children's Health, International Maternal and Child Health (IMCH), International Child Health and Nutrition.
    Boqvist, Sofia
    Bertilsson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    Magnusson, Ulf
    Chandler, Rebecca
    Hur ska vi klara de nya epidemierna?2017Other (Other (popular science, discussion, etc.))
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  • 4160.
    Zmudczynska-Skarbek, Katarzyna
    et al.
    Univ Gdansk, Fac Biol, Dept Vertebrate Ecol & Zool, Wita Stwosza 59, PL-80308 Gdansk, Poland..
    Barcikowski, Mateusz
    Univ Gdansk, Fac Biol, Dept Vertebrate Ecol & Zool, Wita Stwosza 59, PL-80308 Gdansk, Poland..
    Drobniak, Szymon M.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Gwiazdowicz, Dariusz J.
    Poznan Univ Life Sci, Dept Forest Pathol, Wojska Polskiego 71, Poznan, Poland..
    Richard, Pierre
    Univ La Rochelle, CNRS, Littoral Environm & Soc, UMR 7266, 2 Rue Olympe Gouges, F-17000 La Rochelle, France..
    Skubala, Piotr
    Univ Silesia, Dept Ecol, Bankowa 9, PL-40007 Katowice, Poland..
    Stempniewicz, Lech
    Univ Gdansk, Fac Biol, Dept Vertebrate Ecol & Zool, Wita Stwosza 59, PL-80308 Gdansk, Poland..
    Transfer of ornithogenic influence through different trophic levels of the Arctic terrestrial ecosystem of Bjornoya (Bear Island), Svalbard2017In: Soil Biology and Biochemistry, ISSN 0038-0717, E-ISSN 1879-3428, Vol. 115, p. 475-489Article in journal (Refereed)
    Abstract [en]

    Despite widespread recognition of the crucial role seabirds play in the fertilization of nutrient-poor polar terrestrial ecosystems, no studies have attempted a concurrent analysis of the entire or large proportion of an ornithogenically-supported food web. The aim of the current study was to assess the significance of allochthonous nutrient enrichment of key elements of the Bjornoya (Svalbard) terrestrial ecosystem by investigating how different seabird species influenced the characteristics of soil, vegetation, and soil invertebrates (direct ornithogenic effects), and also how those characteristics were interrelated (indirect ornithogenic effects). We sampled in the vicinity of a little auk (Alle alle) colony, and in areas occupied by great skua (Stercorarius skua) and glaucous gull (Larus hyperboreus) nests. Our data demonstrate clear, multi-trophic-level, ornithogenic impacts across the terrestrial ecosystem, with most of the measured parameters of soil, vegetation and invertebrates being altered by proximity to bird nesting areas, though to varying degrees. The ornithogenic effects tended to weaken with increasing complexity of interactions between the ecosystem components, with progression through successive trophic levels. The clearest responses were observed for soil (higher nitrogen stable isotope ratio delta N-15, nitrogen and water content) and vegetation characteristics (higher delta N-15, N content and total cover, lower diversity and species number, and modified community composition). The responses seen in the invertebrate communities were less clear (community composition change), and were only apparent when major invertebrate groups were considered together and for the assumed decomposers: springtails and oribatid mites, while not in the case of predators (mesostigmatid mites and one spider species). There were also suggestions in the data that different seabird species may have different impacts on the surrounding environment, probably due to their different diet and nesting area topography. However, generally, the species of bird was a weaker factor than the presence of a seabird colony or nest itself.

  • 4161.
    Zu, Pengjuan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Effects of Nectar Production and Pollinator Assemblies on Mating Patterns in Orchids2011Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Pollinator visitation patterns should affect pollination success and mating patterns in flowering species. In the orchid family, about one third of the species do not provide any reward for their pollinators. Pollination by deceit is typically associated with low fruit set but may increase the chance of cross-pollination since the pollinator should soon leave the individual plant when there is no reward in the flowers. This may be beneficial if self-fertilisation results in inbreeding depression. I studied the mating patterns of one rewarding and one deceptive orchid in two closely related genera by tracking the fate of stained pollinia. I also conducted controlled crosses to estimate inbreeding depression. The results show that the deceptive orchid Dactylorhiza lapponica has lower pollination success, but higher cross-pollination rate (ca. 90%) than the nectariferous orchid Gymnadenia conopsea (ca. 18% cross-pollination). The results further suggest that in G. conopsea, nocturnal visitors mediate higher geitonogamous pollination rate (ca. 100%) than diurnal visitors (ca. 60%). In both study species, fruits produced from cross-pollination were heavier than fruits produced from selfing. Inbreeding depression for fruit mass did not differ significantly between the two species (δ = 0.21 in D. lapponica and δ = 0.29 in G. conopsea). These data support the hypothesis that pollination by deceit can enhance cross-pollination. A literature study including several rewarding and non-rewarding orchid species indicated lower geitonogamy in the deceptive orchids, but the difference was not statistically significant. 

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  • 4162. Zuccolo, Andrea
    et al.
    Scofield, Douglas G.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    De Paoli, Emanuele
    Morgante, Michele
    The Ty1-copia LTR retroelement family PARTC is highly conserved in conifers over 200 MY of evolution2015In: Gene, ISSN 0378-1119, E-ISSN 1879-0038, Vol. 568, no 1, p. 89-99Article in journal (Refereed)
    Abstract [en]

    Long Terminal Repeat retroelements (LTR-RTs) are a major component of many plant genomes. Although well studied and described in angiosperms, their features and dynamics are poorly understood in gymnosperms. Representative complete copies of a Ty1-copia element isolate in Picea abies and named PARTC were identified in six other conifer species (Picea glauca, Pinus sylvestris, Pinus taeda, Abies sibirica, Taxus baccata and Juniperus communis) covering more than 200 million years of evolution. Here we characterized the structure of this element, assessed its abundance across conifers, studied the modes and timing of its amplification, and evaluated the degree of conservation of its extant copies at nucleotide level over distant species. We demonstrated that the element is ancient, abundant, widespread and its paralogous copies are present in the genera Picea, Pinus and Abies as an LTR-RT family. The amplification leading to the extant copies of PARTC occurred over long evolutionary times spanning 10 s of MY and mostly took place after the speciation of the conifers analyzed. The level of conservation of PARTC is striking and may be explained by low substitution rates and limited removal mechanisms for LTR-RTs. These PARTC features and dynamics are representative of a more general scenario for LTR-RTs in gymnosperms quite different from that characterizing the vast majority of LTR-RT elements in angiosperms. (C) 2015 Elsevier B.V. All rights reserved.

  • 4163.
    Zweifel, Roman
    et al.
    Swiss Fed Inst Forest Snow & Landscape Res WSL, CH-8903 Birmensdorf, Switzerland..
    Sterck, Frank
    Wageningen Univ, Forest Ecol & Management Grp, NL-6708 PB Wageningen, Netherlands..
    Braun, Sabine
    Inst Appl Plant Biol, CH-4108 Witterswil, Switzerland..
    Buchmann, Nina
    Swiss Fed Inst Technol, Dept Environm Syst Sci, Inst Agr Sci, CH-8092 Zurich, Switzerland..
    Eugster, Werner
    Swiss Fed Inst Technol, Dept Environm Syst Sci, Inst Agr Sci, CH-8092 Zurich, Switzerland..
    Gessler, Arthur
    Swiss Fed Inst Forest Snow & Landscape Res WSL, CH-8903 Birmensdorf, Switzerland..
    Häni, Matthias
    Swiss Fed Inst Forest Snow & Landscape Res WSL, CH-8903 Birmensdorf, Switzerland..
    Peters, Richard L.
    Swiss Fed Inst Forest Snow & Landscape Res WSL, CH-8903 Birmensdorf, Switzerland.;Univ Ghent, Lab Plant Ecol, B-9000 Ghent, Belgium..
    Walthert, Lorenz
    Swiss Fed Inst Forest Snow & Landscape Res WSL, CH-8903 Birmensdorf, Switzerland..
    Wilhelm, Micah
    Swiss Fed Inst Forest Snow & Landscape Res WSL, CH-8903 Birmensdorf, Switzerland..
    Zieminska, Kasia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Swiss Fed Inst Forest Snow & Landscape Res WSL, CH-8903 Birmensdorf, Switzerland..
    Etzold, Sophia
    Swiss Fed Inst Forest Snow & Landscape Res WSL, CH-8903 Birmensdorf, Switzerland..
    Why trees grow at night2021In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 231, no 6, p. 2174-2185Article in journal (Refereed)
    Abstract [en]

    The timing of diel stem growth of mature forest trees is still largely unknown, as empirical data with high temporal resolution have not been available so far. Consequently, the effects of day-night conditions on tree growth remained uncertain. Here we present the first comprehensive field study of hourly-resolved radial stem growth of seven temperate tree species, based on 57 million underlying data points over a period of up to 8 yr. We show that trees grow mainly at night, with a peak after midnight, when the vapour pressure deficit (VPD) is among the lowest. A high VPD strictly limits radial stem growth and allows little growth during daylight hours, except in the early morning. Surprisingly, trees also grow in moderately dry soil when the VPD is low. Species-specific differences in diel growth dynamics show that species able to grow earlier during the night are associated with the highest number of hours with growth per year and the largest annual growth increment. We conclude that species with the ability to overcome daily water deficits faster have greater growth potential. Furthermore, we conclude that growth is more sensitive than carbon uptake to dry air, as growth stops before stomata are known to close.

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    fulltext
  • 4164.
    Zwoinska, Martyna K.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Age-specific trade-offs in life-history evolution2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Trade-offs prevent selection from driving all fitness-enhancing traits towards values that would maximize fitness. Life-history trade-offs, such as the one between survival and reproduction are well-studied, yet trade-offs can also involve behavioural or cognitive traits. Because males and females have different routes to successful reproduction, the optimal resolution of life-history trade-offs can differ between the sexes. However, shared genome can constrain the evolution of sex-specific adaptations. In this thesis, I explore the links between sex-specific life histories, cognition and behaviour. I start by linking sex differences in life histories to sex differences in learning performance in the outcrossing nematode Caenorhabditis remanei (Paper I). I report that age-related learning differs between the sexes and that it corresponds to sexual dimorphism in life history. Then, I use experimental evolution to select for learning performance to study the patterns of genetic correlations between learning and life-history traits in both sexes (Paper II). The results demonstrate the correlated evolution of sexual dimorphism in life history indicating sex-specific fitness costs and benefits of learning. In Paper III I use the fruit fly Drosophila melanogaster to ask about the extent to which cognitive and demographic aging are independent. The results reveal that selection for late-life reproduction alone bears no effect on late-life learning and that joint selection on late-life learning and reproduction does not yield lifespan benefits. The selection might have affected, however, female age-specific reproductive effort. Motivated by the questions on aging I proceed to ask why a potent lifespan extending drug – rapamycin affects sexes differently (Paper IV). I take a closer look at the trade-off between growth, lifespan and reproduction and propose that the sex experiencing a stronger relationship between size and fitness pays a higher cost of lifespan extension. Finally, I focus on another sex-specific trait – dispersal (Paper V). I conduct experimental evolution to uncover a negative genetic correlation between dispersal and reproduction and show sex-specific genetic variation for dispersal. In summary, my thesis unravels the complex pattern of interdependence between life-history, behavioural and cognitive traits, where sex emerges as an important factor that can maintain genetic variation for trade-offs.

    List of papers
    1. Sex differences in cognitive ageing: Testing predictions derived from life-history theory in a dioecious nematode
    Open this publication in new window or tab >>Sex differences in cognitive ageing: Testing predictions derived from life-history theory in a dioecious nematode
    2013 (English)In: Experimental Gerontology, ISSN 0531-5565, E-ISSN 1873-6815, Vol. 48, no 12, p. 1469-1472Article in journal (Refereed) Published
    Abstract [en]

    Life-history theory maintains that organisms allocate limited resources to different traits to maximize fitness. Learning ability and memory are costly and known to trade-off with longevity in invertebrates. However, since the relationship between longevity and fitness often differs between the sexes, it is likely that sexes will differentially resolve the trade-off between learning and longevity. We used an established associative learning paradigm in the dioecious nematode Caenorhabditis remanei, which is sexually dimorphic for lifespan, to study age-related learning ability in males and females. In particular, we tested the hypothesis that females (the shorter-lived sex) show higher learning ability than males early in life but senesce faster. Indeed, young females outperformed young males in learning a novel association between an odour (butanone) and food (bacteria). However, while learning ability and offspring production declined rapidly with age in females, males maintained high levels of these traits until mid-age. These results not only demonstrate sexual dimorphismin age-related learning ability but also suggest that it conforms to predictions derived from the life-history theory.

    Keywords
    Ageing, Caenorhabditis, Learning, Life-history, Sex differences, Trade-off
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:uu:diva-213468 (URN)10.1016/j.exger.2013.09.008 (DOI)000327489800012 ()
    Available from: 2013-12-30 Created: 2013-12-23 Last updated: 2017-12-06Bibliographically approved
    2. Selection on learning performance results in the correlated evolution of sexual dimorphism in life history
    Open this publication in new window or tab >>Selection on learning performance results in the correlated evolution of sexual dimorphism in life history
    Show others...
    2016 (English)In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 70, no 2, p. 342-357Article in journal (Refereed) Published
    Abstract [en]

    The evolution of learning can be constrained by trade-offs. As male and female life histories often diverge, the relationship between learning and fitness may differ between the sexes. However, because sexes share much of their genome, intersexual genetic correlations can prevent males and females from reaching their sex-specific optima resulting in intralocus sexual conflict (IaSC). To investigate if IaSC constraints sex-specific evolution of learning, we selected Caenorhabditis remanei nematode females for increased or decreased olfactory learning performance and measured learning, life span (in mated and virgin worms), reproduction, and locomotory activity in both sexes. Males from downward-selected female lines had higher locomotory activity and longer virgin life span but sired fewer progeny than males from upward-selected female lines. In contrast, we found no effect of selection on female reproduction and downward-selected females showed higher locomotory activity but lived shorter as virgins than upward-selected females. Strikingly, selection on learning performance led to the reversal of sexual dimorphism in virgin life span. We thus show sex-specific trade-offs between learning, reproduction, and life span. Our results support the hypothesis that selection on learning performance can shape the evolution of sexually dimorphic life histories via sex-specific genetic correlations.

    Keywords
    Caenorhabditis, cognition, intralocus sexual conflict, olfactory learning, sex-specific life histories
    National Category
    Evolutionary Biology
    Identifiers
    urn:nbn:se:uu:diva-282325 (URN)10.1111/evo.12862 (DOI)000370662500007 ()26787139 (PubMedID)
    Available from: 2016-04-05 Created: 2016-04-05 Last updated: 2017-11-30Bibliographically approved
    3. Experimental evolution of slowed cognitive aging in Drosophila melanogaster
    Open this publication in new window or tab >>Experimental evolution of slowed cognitive aging in Drosophila melanogaster
    2017 (English)In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 71, no 3, p. 662-670Article in journal (Refereed) Published
    Abstract [en]

    Reproductive output and cognitive performance decline in parallel during aging, but it is unknown whether this reflects a shared genetic architecture or merely the declining force of natural selection acting independently on both traits. We used experimental evolution in Drosophila melanogaster to test for the presence of genetic variation for slowed cognitive aging, and assess its independence from that responsible for other traits' decline with age. Replicate experimental populations experienced either joint selection on learning and reproduction at old age (Old + Learning), selection on late-life reproduction alone (Old), or a standard two-week culture regime (Young). Within 20 generations, the Old + Learning populations evolved a slower decline in learning with age than both the Old and Young populations, revealing genetic variation for cognitive aging. We found little evidence for a genetic correlation between cognitive and demographic aging: although the Old + Learning populations tended to show higher late-life fecundity than Old populations, they did not live longer. Likewise, selection for late reproduction alone did not result in improved late-life learning. Our results demonstrate that Drosophila harbor genetic variation for cognitive aging that is largely independent from genetic variation for demographic aging and suggest that these two aspects of aging may not necessarily follow the same trajectories.

    Place, publisher, year, edition, pages
    WILEY, 2017
    Keywords
    Cognitive aging, Drosophila, experimental evolution, genetic architecture, learning, trade-off
    National Category
    Genetics
    Identifiers
    urn:nbn:se:uu:diva-320841 (URN)10.1111/evo.13156 (DOI)000396039000011 ()28000915 (PubMedID)
    Funder
    The Royal Swedish Academy of SciencesSwedish Research CouncilEU, European Research Council
    Available from: 2017-04-26 Created: 2017-04-26 Last updated: 2017-09-07Bibliographically approved
    4. Sex-specific Tradeoffs With Growth and Fitness Following Life-span Extension by Rapamycin in an Outcrossing Nematode, Caenorhabditis remanei
    Open this publication in new window or tab >>Sex-specific Tradeoffs With Growth and Fitness Following Life-span Extension by Rapamycin in an Outcrossing Nematode, Caenorhabditis remanei
    Show others...
    2016 (English)In: The journals of gerontology. Series A, Biological sciences and medical sciences, ISSN 1079-5006, E-ISSN 1758-535X, Vol. 71, no 7, p. 882-890Article in journal (Refereed) Published
    Abstract [en]

    Rapamycin inhibits the nutrient-sensing TOR pathway and extends life span in a wide range of organisms. Although life-span extension usually differs between the sexes, the reason for this is poorly understood. Because TOR influences growth, rapamycin likely affects life-history traits such as growth and reproduction. Sexes have different life-history strategies, and theory predicts that they will resolve the tradeoffs between growth, reproduction, and life span differently. Specifically, in taxa with female-biased sexual size dimorphism, reduced growth may have smaller effects on male fitness. We investigated the effects of juvenile, adult, or life-long rapamycin treatment on growth, reproduction, life span, and individual fitness in the outcrossing nematode Caenorhabditis remanei. Life-long exposure to rapamycin always resulted in the strongest response, whereas postreproductive exposure did not affect life span. Although rapamycin resulted in longer life span and smaller size in males, male individual fitness was not affected. In contrast, size and fitness were negatively affected in females, whereas life span was only extended under high rapamycin concentrations. Our results support the hypothesis that rapamycin affects key life-history traits in a sex-specific manner. We argue that the fitness cost of life-span extension will be sex specific and propose that the smaller sex generally pay less while enjoying stronger life-span increase.

    Keywords
    Antiaging, Evolution, Longevity
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:uu:diva-304528 (URN)10.1093/gerona/glv174 (DOI)000381209900006 ()26472877 (PubMedID)
    Funder
    Swedish Research Council, C0636601, 621-2013-4828EU, European Research Council, St-G 2010 AGINGSEXDIFF 260885
    Available from: 2016-10-12 Created: 2016-10-06 Last updated: 2022-01-29Bibliographically approved
    5. Artificial selection for increased dispersal results in lower fitness
    Open this publication in new window or tab >>Artificial selection for increased dispersal results in lower fitness
    Show others...
    2020 (English)In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 33, no 2, p. 217-224Article in journal (Refereed) Published
    Abstract [en]

    Dispersal often covaries with other traits, and this covariation was shown to have a genetic basis. Here, we wanted to explore to what extent genetic constraints and correlational selection can explain patterns of covariation between dispersal and key life-history traits-lifespan and reproduction. A prediction from the fitness-associated dispersal hypothesis was that lower genetic quality is associated with higher dispersal propensity as driven by the benefits of genetic mixing. We wanted to contrast it with a prediction from a different model that individuals putting more emphasis on current rather than future reproduction disperse more, as they are expected to be more risk-prone and exploratory. However, if dispersal has inherent costs, this will also result in a negative genetic correlation between higher rates of dispersal and some aspects of performance. To explore this issue, we used the dioecious nematode Caenorhabditis remanei and selected for increased and decreased dispersal propensity for 10 generations, followed by five generations of relaxed selection. Dispersal propensity responded to selection, and females from high-dispersal lines dispersed more than females from low-dispersal lines. Females selected for increased dispersal propensity produced fewer offspring and were more likely to die from matricide, which is associated with a low physiological condition in Caenorhabditis nematodes. There was no evidence for differences in age-specific reproductive effort between high- and low-dispersal females. Rather, reproductive output of high-dispersal females was consistently reduced. We argue that our data provide support for the fitness-associated dispersal hypothesis.

    Keywords
    artificial selection, Caenorhabditis, dispersal syndromes, fitness-associated dispersal, life-history theory
    National Category
    Evolutionary Biology
    Research subject
    Biology with specialization in Animal Ecology
    Identifiers
    urn:nbn:se:uu:diva-329033 (URN)10.1111/jeb.13563 (DOI)000498113300001 ()31677316 (PubMedID)
    Note

    Titel in Thesis List of papers:

    Fitness-associated dispersal: selection for increased dispersal results in lower fitness

    Available from: 2017-09-06 Created: 2017-09-06 Last updated: 2021-03-22Bibliographically approved
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  • 4165.
    Zwoinska, Martyna K.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Kolm, Niclas
    Maklakov, Alexei A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sex differences in cognitive ageing: Testing predictions derived from life-history theory in a dioecious nematode2013In: Experimental Gerontology, ISSN 0531-5565, E-ISSN 1873-6815, Vol. 48, no 12, p. 1469-1472Article in journal (Refereed)
    Abstract [en]

    Life-history theory maintains that organisms allocate limited resources to different traits to maximize fitness. Learning ability and memory are costly and known to trade-off with longevity in invertebrates. However, since the relationship between longevity and fitness often differs between the sexes, it is likely that sexes will differentially resolve the trade-off between learning and longevity. We used an established associative learning paradigm in the dioecious nematode Caenorhabditis remanei, which is sexually dimorphic for lifespan, to study age-related learning ability in males and females. In particular, we tested the hypothesis that females (the shorter-lived sex) show higher learning ability than males early in life but senesce faster. Indeed, young females outperformed young males in learning a novel association between an odour (butanone) and food (bacteria). However, while learning ability and offspring production declined rapidly with age in females, males maintained high levels of these traits until mid-age. These results not only demonstrate sexual dimorphismin age-related learning ability but also suggest that it conforms to predictions derived from the life-history theory.

  • 4166.
    Zwoinska, Martyna K.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Stockholm Univ, Dept Zool, Stockholm, Sweden.
    Larva, Tuuli
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sekajova, Zuzana
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Carlsson, Hanne
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ East Anglia, Sch Biol Sci, Norwich, Norfolk, England.
    Meurling, Sara
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Maklakov, Alexei A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ East Anglia, Sch Biol Sci, Norwich, Norfolk, England.
    Artificial selection for increased dispersal results in lower fitness2020In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 33, no 2, p. 217-224Article in journal (Refereed)
    Abstract [en]

    Dispersal often covaries with other traits, and this covariation was shown to have a genetic basis. Here, we wanted to explore to what extent genetic constraints and correlational selection can explain patterns of covariation between dispersal and key life-history traits-lifespan and reproduction. A prediction from the fitness-associated dispersal hypothesis was that lower genetic quality is associated with higher dispersal propensity as driven by the benefits of genetic mixing. We wanted to contrast it with a prediction from a different model that individuals putting more emphasis on current rather than future reproduction disperse more, as they are expected to be more risk-prone and exploratory. However, if dispersal has inherent costs, this will also result in a negative genetic correlation between higher rates of dispersal and some aspects of performance. To explore this issue, we used the dioecious nematode Caenorhabditis remanei and selected for increased and decreased dispersal propensity for 10 generations, followed by five generations of relaxed selection. Dispersal propensity responded to selection, and females from high-dispersal lines dispersed more than females from low-dispersal lines. Females selected for increased dispersal propensity produced fewer offspring and were more likely to die from matricide, which is associated with a low physiological condition in Caenorhabditis nematodes. There was no evidence for differences in age-specific reproductive effort between high- and low-dispersal females. Rather, reproductive output of high-dispersal females was consistently reduced. We argue that our data provide support for the fitness-associated dispersal hypothesis.

  • 4167.
    Zwoinska, Martyna K.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lind, Martin I.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Cortazar-Chinarro, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Ramsden, Mark
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Maklakov, Alexei A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Selection on learning performance results in the correlated evolution of sexual dimorphism in life history2016In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 70, no 2, p. 342-357Article in journal (Refereed)
    Abstract [en]

    The evolution of learning can be constrained by trade-offs. As male and female life histories often diverge, the relationship between learning and fitness may differ between the sexes. However, because sexes share much of their genome, intersexual genetic correlations can prevent males and females from reaching their sex-specific optima resulting in intralocus sexual conflict (IaSC). To investigate if IaSC constraints sex-specific evolution of learning, we selected Caenorhabditis remanei nematode females for increased or decreased olfactory learning performance and measured learning, life span (in mated and virgin worms), reproduction, and locomotory activity in both sexes. Males from downward-selected female lines had higher locomotory activity and longer virgin life span but sired fewer progeny than males from upward-selected female lines. In contrast, we found no effect of selection on female reproduction and downward-selected females showed higher locomotory activity but lived shorter as virgins than upward-selected females. Strikingly, selection on learning performance led to the reversal of sexual dimorphism in virgin life span. We thus show sex-specific trade-offs between learning, reproduction, and life span. Our results support the hypothesis that selection on learning performance can shape the evolution of sexually dimorphic life histories via sex-specific genetic correlations.

  • 4168.
    Zwoinska, Martyna K.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ Lausanne, Dept Ecol & Evolut, CH-1015 Lausanne, Switzerland..
    Maklakov, Alexei A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Kawecki, Tadeusz J.
    Univ Lausanne, Dept Ecol & Evolut, CH-1015 Lausanne, Switzerland..
    Hollis, Brian
    Univ Lausanne, Dept Ecol & Evolut, CH-1015 Lausanne, Switzerland.;Ecole Polytech Fed Lausanne, Sch Life Sci, Lausanne, Switzerland..
    Experimental evolution of slowed cognitive aging in Drosophila melanogaster2017In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 71, no 3, p. 662-670Article in journal (Refereed)
    Abstract [en]

    Reproductive output and cognitive performance decline in parallel during aging, but it is unknown whether this reflects a shared genetic architecture or merely the declining force of natural selection acting independently on both traits. We used experimental evolution in Drosophila melanogaster to test for the presence of genetic variation for slowed cognitive aging, and assess its independence from that responsible for other traits' decline with age. Replicate experimental populations experienced either joint selection on learning and reproduction at old age (Old + Learning), selection on late-life reproduction alone (Old), or a standard two-week culture regime (Young). Within 20 generations, the Old + Learning populations evolved a slower decline in learning with age than both the Old and Young populations, revealing genetic variation for cognitive aging. We found little evidence for a genetic correlation between cognitive and demographic aging: although the Old + Learning populations tended to show higher late-life fecundity than Old populations, they did not live longer. Likewise, selection for late reproduction alone did not result in improved late-life learning. Our results demonstrate that Drosophila harbor genetic variation for cognitive aging that is largely independent from genetic variation for demographic aging and suggest that these two aspects of aging may not necessarily follow the same trajectories.

    Download full text (pdf)
    fulltext
  • 4169.
    Zwoinska, Martyna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lind, Martin I.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Maklakov, Alexei A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sexual Conflict: Male Control of Female Longevity2014In: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 24, no 5, p. R196-R198Article in journal (Other academic)
  • 4170.
    Åberg, Jan
    et al.
    Department of Ecology and Environmental Science, Umeå University.
    Wallin, Marcus B.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Evaluating a fast headspace method for measuring DIC and subsequent calculation of pCO2 in freshwater systems2014In: Inland Water Biology, ISSN 1995-0829, E-ISSN 1995-0837, Vol. 4, no 2, p. 157-166Article in journal (Refereed)
    Abstract [en]

    A variety of different sampling and analysis methods are found in the literature for determining carbon dioxide (CO2) in freshwaters, methods that rarely have been evaluated or compared. Here we present an evaluation of an acidified headspace method (AHS) in which the dissolved inorganic carbon (DIC) is measured from an acidified sample and the partial pressure (pCO2) is calculated from DIC using pH and water temperature. We include information on practical sampling, accuracy, and precision of the DIC/pCO2 determination and a storage test of samples. The pCO2 determined from the AHS method is compared to that obtained from the more widely used direct headspace method (DHS) in which CO2 is equilibrated between the water and gas phases at ambient pH. The method was tested under both controlled laboratory conditions as well as wintertime field sampling. The accuracy of the DIC detection was on average 99% based on prepared standard solutions. The pCO2 determination in lab, using the DHS method as a reference, showed no significant difference, although the discrepancy between the methods was larger in samples with <1000 µatm. The precision of the pCO2 determination was on average ±4.3%, which was slightly better than the DHS method (±6.7%). In the field, the AHS method determined on average 10% higher pCO2 than the DHS method, which was explained by the extreme winter conditions (below −20 °C) at sampling that affected the sampling procedure of the DHS method. Although samples were acidified to pH 2, respiration processes were still occurring (at a low rate), and we recommend that analyses are conducted within 3 days from sampling. The AHS method was found to be a robust method to determine DIC and pCO2 in acidic to pH-neutral freshwater systems. The simple and quick sampling procedure makes the method suitable for time-limited sampling campaigns and sampling in cold climate.

  • 4171.
    Ågren, Arvid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Eine Idee mit Biss2022In: Merkur, ISSN 0026-0096, Vol. 76, no 872, p. 75-82Article in journal (Other academic)
  • 4172.
    Ågren, Arvid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Structure, Evidence, and Heuristic: Evolutionary Biology, Economics, and the Philosophy of Their Relationship. Routledge Studies in the Philosophy of Science by Armin W. Schulz2022In: The Quarterly review of biology, ISSN 0033-5770, E-ISSN 1539-7718, Vol. 97, no 1, p. 50-50Article, book review (Other academic)
  • 4173.
    Ågren, Arvid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology. Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA..
    Haig, David
    Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA..
    McCOY, Dakota E.
    Harvard Univ, Dept Organism & Evolutionary Biol, Cambridge, MA 02138 USA.;Stanford Univ, Hopkins Marine Lab, Stanford, CA 94305 USA.;Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA.;Duke Univ, Dept Biol, Durham, NC 27708 USA..
    Meiosis solved the problem of gerrymandering2022In: Journal of Genetics, ISSN 0022-1333, E-ISSN 0973-7731, Vol. 101, no 2, article id 38Article in journal (Refereed)
    Abstract [en]

    Gerrymandering, the structuring of voting districts to favour certain politicians and political groups, undermines fair elections and presents a serious challenge to democracy. We introduce a solution to gerrymandering inspired by the biological process of cell division in sexually reproducing organisms, meiosis, in which the boundaries of electorates are frequently redrawn by randomizing algorithms. By demonstrating the deep parallels between meiosis and John Rawls's concept of a 'veil of ignorance', we also show how one of the biggest threats to the integrity of meiosis--selfish genetic elements, genes that promote their own transmission at the expense of organismal fitness--can inspire another potential advantage to frequent random redistricting.

  • 4174.
    Ågren, J. Arvid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Structure, Evidence, and Heuristic: Evolutionary Biology, Economics, and the Philosophy of Their Relationship. Routledge Studies in the Philosophy of Science by Armin W. Schulz. New York: Routledge (Taylor & Francis Group). $160.00. xi + 228 p.; ill.; index. ISBN: 978-0-367-46590-2 (hc); 978-1-003-03024-9 (eb). 20202022In: The Quarterly review of biology, ISSN 0033-5770, E-ISSN 1539-7718, Vol. 97, no 1, p. 50-50Article, book review (Other academic)
  • 4175.
    Ågren, J. Arvid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Patten, Manus M.
    Georgetown Univ, Dept Biol, Washington, DC 20057 USA.
    Genetic conflicts and the case for licensed anthropomorphizing2022In: Behavioral Ecology and Sociobiology, ISSN 0340-5443, E-ISSN 1432-0762, Vol. 76, no 12, article id 166Article, review/survey (Refereed)
    Abstract [en]

    The use of intentional language in biology is controversial. It has been commonly applied by researchers in behavioral ecology, who have not shied away from employing agential thinking or even anthropomorphisms, but has been rarer among researchers from more mechanistic corners of the discipline, such as population genetics. One research area where these traditions come into contact-and occasionally clash-is the study of genetic conflicts, and its history offers a good window to the debate over the use of intentional language in biology. We review this debate, paying particular attention to how this interaction has played out in work on genomic imprinting and sex chromosomes. In light of this, we advocate for a synthesis of the two approaches, a form of licensed anthropomorphizing. Here, agential thinking's creative potential and its ability to identify the fulcrum of evolutionary pressure are combined with the rigidity of formal mathematical modeling.

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  • 4176.
    Ågren, J. Arvid
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology. Cleveland Clin Fdn, Lerner Res Inst, Cleveland, OH 44195 USA..
    Scott, Jacob G.
    Cleveland Clin Fdn, Lerner Res Inst, Cleveland, OH 44195 USA.;Cleveland Clin, Dept Radiat Oncol, Cleveland, OH USA.;Case Western Reserve Sch Med, Cleveland, OH USA..
    Viruses, cancers, and evolutionary biology in the clinic: a commentary on Leeks et al. 20232023In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 36, no 11, p. 1587-1589Article in journal (Other academic)
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  • 4177.
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Pollinators, herbivores, and the evolution of floral traits2019In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 364, no 6436, p. 122-123Article in journal (Other academic)
  • 4178.
    Ågren, Jon
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Hellström, Frida
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Toräng, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ehrlén, Johan
    Stockholm Univ, Dept Ecol Environm & Plant Sci, SE-10691 Stockholm, Sweden.
    Mutualists and antagonists drive among-population variation in selection and evolution of floral display in a perennial herb2013In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 110, no 45, p. 18202-18207Article in journal (Refereed)
    Abstract [en]

    Spatial variation in the direction of selection drives the evolution of adaptive differentiation. However, few experimental studies have examined the relative importance of different environmental factors for variation in selection and evolutionary trajectories in natural populations. Here, we combine 8 y of observational data and field experiments to assess the relative importance of mutualistic and antagonistic interactions for spatial variation in selection and short-term evolution of a genetically based floral display dimorphism in the short-lived perennial herb Primula farinosa. Natural populations of this species include two floral morphs: long-scaped plants that present their flowers well above the ground and short-scaped plants with flowers positioned close to the ground. The direction and magnitude of selection on scape morph varied among populations, and so did the frequency of the short morph (median 19%, range 0–100%; n = 69 populations). A field experiment replicated at four sites demonstrated that variation in the strength of interactions with grazers and pollinators were responsible for among-population differences in relative fitness of the two morphs. Selection exerted by grazers favored the short-scaped morph, whereas pollinator-mediated selection favored the long-scaped morph. Moreover, variation in selection among natural populations was associated with differences in morph frequency change, and the experimental removal of grazers at nine sites significantly reduced the frequency of the short-scaped morph over 8 y. The results demonstrate that spatial variation in intensity of grazing and pollination produces a selection mosaic, and that changes in biotic interactions can trigger rapid genetic changes in natural plant populations.

  • 4179.
    Ågren, Jon
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Oakley, C. G.
    McKay, J. K.
    Lovell, J. T.
    Schemske, D. W.
    Genetic mapping of adaptation reveals fitness trade-offs in Arabidopsis thaliana2013In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 110, no 52, p. 21077-21087Article in journal (Refereed)
    Abstract [en]

    Organisms inhabiting different environments are often locally adapted, and yet despite a considerable body of theory, the genetic basis of local adaptation is poorly understood. Unanswered questions include the number and effect sizes of adaptive loci, whether locally favored loci reduce fitness elsewhere (i.e., fitness tradeoffs), and whether a lack of genetic variation limits adaptation. To address these questions, we mapped quantitative trait loci (QTL) for total fitness in 398 recombinant inbred lines derived from a cross between locally adapted populations of the highly selfing plant Arabidopsis thaliana from Sweden and Italy and grown for 3 consecutive years at the parental sites (>40,000 plants monitored). We show that local adaptation is controlled by relatively few genomic regions of small to modest effect. A third of the 15 fitness QTL we detected showed evidence of tradeoffs, which contrasts with the minimal evidence for fitness tradeoffs found in previous studies. This difference may reflect the power of our multiyear study to distinguish conditionally neutral QTL from those that reflect fitness tradeoffs. In Sweden, but not in Italy, the local genotype underlying fitness QTL was often maladaptive, suggesting that adaptation there is constrained by a lack of adaptive genetic variation, attributable perhaps to genetic bottlenecks during postglacial colonization of Scandinavia or to recent changes in selection regime caused by climate change. Our results suggest that adaptation to markedly different environments can be achieved through changes in relatively few genomic regions, that fitness tradeoffs are common, and that lack of genetic variation can limit adaptation.

  • 4180.
    Ågren, Jon
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Oakley, Christopher G.
    Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA. WWF Norway, Postboks 6784, N-0130 Oslo, Norway..
    Lundemo, Sverre
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Schemske, Douglas W.
    Michigan State Univ, Dept Plant Biol, E Lansing, MI 48824 USA.;Michigan State Univ, WK Kellogg Biol Stn, E Lansing, MI 48824 USA..
    Adaptive divergence in flowering time among natural populations of Arabidopsis thaliana: Estimates of selection and QTL mapping2017In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 71, no 3, p. 550-564Article in journal (Refereed)
    Abstract [en]

    To identify the ecological and genetic mechanisms of local adaptation requires estimating selection on traits, identifying their genetic basis, and evaluating whether divergence in adaptive traits is due to conditional neutrality or genetic trade-offs. To this end, we conducted field experiments for three years using recombinant inbred lines (RILs) derived from two ecotypes of Arabidopsis thaliana (Italy, Sweden), and at each parental site examined selection on flowering time and mapped quantitative trait loci (QTL). There was strong selection for early flowering in Italy, but weak selection in Sweden. Eleven distinct flowering time QTL were detected, and for each the Italian genotype caused earlier flowering. Twenty-seven candidate genes were identified, two of which (FLC and VIN3) appear under major flowering time QTL in Italy. Seven of eight QTL in Italy with narrow credible intervals colocalized with previously reported fitness QTL, in comparison to three of four in Sweden. The results demonstrate that the magnitude of selection on flowering time differs strikingly between our study populations, that the genetic basis of flowering time variation is multigenic with some QTL of large effect, and suggest that divergence in flowering time between ecotypes is due mainly to conditional neutrality.

  • 4181.
    Ågren, Jon
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Schemske, Douglas W.
    Deceit pollination in Begonia2000In: Monteverde: ecology and conservation of a tropical cloud forest, Oxford University Press, 2000, p. 279-281Chapter in book (Refereed)
  • 4182.
    Ågren, Jon
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Schemske, Douglas W.
    Reciprocal transplants demonstrate strong adaptive differentiation of the model organism Arabidopsis thaliana in its native range2012In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 194, no 4, p. 1112-1122Article in journal (Refereed)
    Abstract [en]

    To quantify adaptive differentiation in the model plant Arabidopsis thaliana, we conducted reciprocal transplant experiments for five years between two European populations, one near the northern edge of the native range (Sweden) and one near the southern edge (Italy). We planted seeds (years 13) and seedlings (years 45), and estimated fitness as the number of fruits produced per seed or seedling planted. In eight of the 10 possible site x year comparisons, the fitness of the local population was significantly higher than that of the nonlocal population (3.122.2 times higher at the southern site, and 1.73.6 times higher at the northern site); in the remaining two comparisons no significant difference was recorded. At both sites, the local genotype had higher survival than the nonlocal genotype, and at the Italian site, the local genotype also had higher fecundity. Across years, the relative survival of the Italian genotype at the northern site decreased with decreasing winter soil temperature. The results provide evidence of strong adaptive differentiation between natural populations of A similar to thaliana and indicate that differences in tolerance to freezing contributed to fitness variation at the northern site. In ongoing work, we explore the functional and genetic basis of this adaptive differentiation.

  • 4183.
    Ålund, Murielle
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Gametes and speciation: from prezygotic to postzygotic isolation2012Report (Other academic)
    Abstract [en]

    Speciation lies at the heart of evolutionary biology and researchers have been trying to understand the mechanisms leading to the evolution of reproductive isolation since over 250 years. Premating barriers (i.e. barriers preventing heterospecific individuals to mate with each other) and extrinsic postzygotic isolation (i.e. environmental factors affecting the fitness of hybrid individuals) have been studied in many taxa. However, little is known about what is happening at the gametic level, both before heterospecific fertilization (i.e. postmating prezygotic or gametic isolation) and in hybrid individuals (i.e. intrinsic postzygotic incompatibilities). In this essay, I will give an overview of the role gametes play in the evolution of reproductive isolation. I conclude that gametes and reproductive proteins evolve quickly, under strong influence of sexual and sexually antagonistic selection. Gametes are very diverse between species and sperm competition and female cryptic choice can lead to higher fertilization success of sperm from conspecific males. In the hybrid offspring, spermatogenesis can be easily disturbed by small differences in gene expression and this leads to a greater number of genes causing hybrid sterility compared to hybrid inviability among taxa. Following Haldane’s rule, the heterogametic sex is the first to be affected by hybrid incompatibilities, but different mechanisms seem to cause inviability and sterility and taxa with heterogametic males or heterogametic females might be affected differently. I end this review by focusing on one particular model system for studying speciation: the Ficedula flycatchers. Much is known about the ecological factors affecting speciation and hybridization between pied and collared flycatchers and new molecular data give insights into the genetics of speciation, but the role of gametes has not been studied in this system. Studies on gamete divergence and hybrid gamete production in the flycatchers will allow us to get a better idea of the role of gametes in speciation in a wild organism with homogametic males.

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  • 4184.
    Ålund, Murielle
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Cenzer, Meredith
    Univ Chicago, Dept Ecol & Evolut, Chicago, IL 60637 USA..
    Bierne, Nicolas
    Univ Montpellier, ISEM, CNRS, IRD, F-34095 Montpellier, France..
    Boughman, Janette W.
    Michigan State Univ, Dept Integrat Biol, E Lansing, MI 48824 USA..
    Cerca, Jose
    Univ Oslo, Ctr Ecol & Evolutionary Synth, Dept Biosci, CEES, N-0316 Oslo, Norway..
    Comerford, Mattheau S.
    UMass Boston, Biol Dept, Boston, MA 02125 USA..
    Culicchi, Alessandro
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Langerhans, Brian
    North Carolina State Univ, Dept Biol Sci, Raleigh, NC 27695 USA..
    Mcfarlane, S. Eryn
    Univ Wyoming, Dept Bot, Laramie, WY 82071 USA.;York Univ, Dept Biol, Toronto, ON M3J 1P3, Canada..
    Most, Markus H.
    Univ Innsbruck, Res Dept Limnol, A-6020 Innsbruck, Austria..
    North, Henry
    Univ Cambridge, Dept Zool, Cambridge CB2 3EJ, England..
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Ravinet, Mark
    Univ Nottingham, Sch Life Sci, Univ Pk, Nottingham NG7 2RD, England..
    Svanbäck, Richard
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Taylor, Scott A.
    Univ Colorado Boulder, Dept Ecol & Evolutionary Biol, Boulder, CO 80309 USA..
    Anthropogenic Change and the Process of Speciation2023In: Cold Spring Harbor Perspectives in Biology, E-ISSN 1943-0264, Vol. 15, no 12, article id a041455Article in journal (Refereed)
    Abstract [en]

    Anthropogenic impacts on the environment alter speciation processes by affecting both geographical contexts and selection patterns on a worldwide scale. Here we review evidence of these effects. We find that human activities often generate spatial isolation between populations and thereby promote genetic divergence but also frequently cause sudden secondary contact and hybridization between diverging lineages. Human-caused environmental changes produce new ecological niches, altering selection in diverse ways that can drive diversification; but changes also often remove niches and cause extirpations. Human impacts that alter selection regimes are widespread and strong in magnitude, ranging from local changes in biotic and abiotic conditions to direct harvesting to global climate change. Altered selection, and evolutionary responses to it, impacts early-stage divergence of lineages, but does not necessarily lead toward speciation and persistence of separate species. Altogether, humans both promote and hinder speciation, although new species would form very slowly relative to anthropogenic hybridization, which can be nearly instantaneous. Speculating about the future of speciation, we highlight two key conclusions: (1) Humans will have a large influence on extinction and "despeciation" dynamics in the short term and on early-stage lineage divergence, and thus potentially speciation in the longer term, and (2) long-term monitoring combined with easily dated anthropogenic changes will improve our understanding of the processes of speciation. We can use this knowledge to preserve and restore ecosystems in ways that promote (re-)diversification, increasing future opportunities of speciation and enhancing biodiversity.

  • 4185.
    Ålund, Murielle
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Department of Integrative Biology, Michigan State University, East Lansing, MI, USA;BEACON Center for the Study of Evolution in Action, Michigan State University, East Lansing, MI, USA.
    Harper, Brooke
    Department of Integrative Biology, Michigan State University, East Lansing, MI, USA.
    Kjærnested, Sigurlaug
    Department of Aquaculture &amp; Fish Biology, Hólar University College, Sauðárkrókur, Iceland.
    Ohl, Julian E.
    Faculty of Environment and Natural Resources, University of Iceland, Reykjavík, Iceland.
    Phillips, John G.
    Department of Integrative Biology, Michigan State University, East Lansing, MI, USA;BEACON Center for the Study of Evolution in Action, Michigan State University, East Lansing, MI, USA;Department of Biological Sciences, University of Idaho, Moscow, ID, USA.
    Sattler, Jessica
    Department of Biology, Miami University, Oxford, OH, USA.
    Thompson, Jared
    Department of Integrative Biology, Michigan State University, East Lansing, MI, USA.
    Varg, Javier Edo.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Department of Integrative Biology, Michigan State University, East Lansing, MI, USA.
    Wargenau, Sven
    Institute of Cell Dynamics and Imaging, University of Münster, Münster, Germany.
    Boughman, Janette W.
    Department of Integrative Biology, Michigan State University, East Lansing, MI, USA;BEACON Center for the Study of Evolution in Action, Michigan State University, East Lansing, MI, USA.
    Keagy, Jason
    Department of Ecosystem Science and Management, The Pennsylvania State University, University Park, PA, USA.
    Sensory environment affects Icelandic threespine stickleback's anti-predator escape behaviour2022In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 289, no 1972, article id 20220044Article in journal (Refereed)
    Abstract [en]

    Human-induced changes in climate and habitats push populations to adapt to novel environments, including new sensory conditions, such as reduced visibility. We studied how colonizing newly formed glacial lakes with turbidity-induced low-visibility affects anti-predator behaviour in Icelandic threespine sticklebacks. We tested nearly 400 fish from 15 populations and four habitat types varying in visibility and colonization history in their reaction to two predator cues (mechano-visual versus olfactory) in high versus low-visibility light treatments. Fish reacted differently to the cues and were affected by lighting environment, confirming that cue modality and light levels are important for predator detection and evasion. Fish from spring-fed lakes, especially from the highlands (likely more diverged from marine fish than lowland fish), reacted fastest to mechano-visual cues and were generally most active. Highland glacial fish showed strong responses to olfactory cues and, counter to predictions from the flexible stem hypothesis, the greatest plasticity in response to light levels. This study, leveraging natural, repeated invasions of novel sensory habitats, (i) illustrates rapid changes in anti-predator behaviour that follow due to adaptation, early life experience, or both, and (ii) suggests an additional role for behavioural plasticity enabling population persistence in the face of frequent changes in environmental conditions.

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  • 4186.
    Ålund, Murielle
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Immler, Simone
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Rice, Amber M.
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Low fertility of wild hybrid male flycatchers despite recent divergence2013In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 9, no 3, article id 20130169Article in journal (Refereed)
    Abstract [en]

    Postzygotic isolation may be important for maintaining species boundaries, particularly when premating barriers are incomplete. Little is known about the course of events leading from minor environmental mismatches affecting hybrid fitness to severe genetic incompatibilities causing sterility or inviability. We investigated whether reduced reproductive success of hybrid males was caused by suboptimal sperm traits or by more severe genetic incompatibilities in a hybrid zone of pied (Ficedula hypoleuca) and collared flycatchers (F. albicollis) on the island of Oland, Sweden. About 4 per cent hybridization is observed in this population and all female hybrids are sterile. We found no sperm in the ejaculates of most sampled hybrid males, and sperm with abnormal morphology in two hybrids. Furthermore, none of the hybrids sired any offspring because of high levels of hatching failure and extra-pair paternity in their nests. These results from a natural hybrid zone suggest that the spermatogenesis of hybrid males may become disrupted despite little genetic divergence between the parental species.

  • 4187.
    Ålund, Murielle
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Michigan State Univ, Dept Integrat Biol, Giltner Hall 362, E Lansing, MI 48825 USA.
    Persson Schmiterlöw, Siri
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    McFarlane, S. Eryn
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ Edinburgh, Inst Evolutionary Biol, Charlotte Auerbach Rd, Edinburgh EH9 3FL, Midlothian, Scotland.
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Optimal sperm length for high siring success depends on forehead patch size in collared flycatchers2018In: Behavioral Ecology, ISSN 1045-2249, E-ISSN 1465-7279, Vol. 29, no 6, p. 1436-1443Article in journal (Refereed)
    Abstract [en]

    Dominance over rivals, sexual attractiveness, and highly efficient ejaculates are 3 important contributors of male fertilization success but theories about how primary and secondary sexual characters may co-evolve largely remain to be tested. We investigated how variation in a sexual signal (forehead patch size) and sperm morphology jointly affected siring success of 70 males in a natural population of collared flycatchers. We show that the optimal sperm length to attain high relative fertilization success depended on the size of a male's secondary sexual character. Males with small forehead patches sired more offspring in their nest when they produced long sperm and vice-versa. These results are not compatible with theories based on simple relationships between display traits and sperm "quality" but imply that the optimal fertilization strategy (and hence optimal sperm traits) differs between males even in a predominantly socially monogamous population with moderate extra-pair paternity rates. Thus, a better knowledge of the complex chain of behavioural interactions between the sexes and their gametes is needed for a complete understanding of how sexual selection operates in nature.

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  • 4188.
    Ålund, Murielle
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Persson-Schmitterlöw, Siri
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    McFarlane, S. Eryn
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Revisiting the definition of “sperm quality”: selection on sperm length depends on a male’s attractiveness and dominance in wild collared flycatchersManuscript (preprint) (Other academic)
    Abstract [en]

    Dominance over rivals, sexual attractiveness and highly efficient ejaculates are all known to be essential for male fertilization success but the theories of how primary and secondary sexual characters may co-evolve largely remain to be tested. Here, we measure sperm morphology in 131 wild-caught collared flycatchers over a four-year period and investigate the links between male display traits, sperm characteristics and siring success among 425 offspring sired by 71 of these males. We show that the optimal sperm length to attain high relative fertilization success depends on the size of a male’s secondary sexual character. Males with small ornaments sire more offspring in their own nest when they produce long sperm and vice-versa. These results are not compatible with theories based on simple relationships between secondary sexual traits and sperm “quality” but imply that the optimal fertilization strategy (and hence optimal sperm traits) differ between males even in a predominantly socially monogamous population with moderate extra-pair copulation rates. Thus, a better knowledge of the complex chain of behavioural interactions between the sexes and their gametes is needed for a complete understanding of how sexual selection operates in nature.

  • 4189.
    Ålund, Murielle
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Segami, Carolina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Zhu, Yishu
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Menon, Navaneeth
    Jones, William
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Hybrid viability across life-stages in a natural contact zoneManuscript (preprint) (Other academic)
    Abstract [en]

    Hybrid inviability is an important post-zygotic reproductive barrier between species but emerging signs of intrinsic dysfunction can be difficult to study across the lifespan of natural hybrids. Here, we use a combination of long-term monitoring of individuals in a natural hybrid zone of Ficedula flycatchers together with information on extra-pair paternity and mitochondrial DNA identification with the main goal of detecting emerging signs of intrinsic hybrid inviability across the entire lifespan of these naturally hybridizing birds. We also evaluate possible evidence of Darwin’s corollary to Haldane’s rule, which predicts asymmetries in the degree of inviability between hybrids resulting from reciprocal crosses, due to incompatible genetic factors with sex-specific inheritance patterns. We found higher hatching failure among mixed-species pairs, which could indicate early developmental impairments associated with specific parental genetic combinations. Adult hybrids had a higher basal mortality rate than both parental species, and different age-specific mortality trajectories. There were some signs of differences in age-independent mortality rates between the reciprocal hybrid crosses, with hybrid individuals with a pied flycatcher mother experiencing slightly increased mortality rates later in life. Clashes between the maternally inherited mitochondrial genome and part of the paternally inherited nuclear genome in these hybrids, leading to reduced efficiency of the cellular energy metabolism, are good candidates underlying intrinsic postzygotic isolation in this system.

  • 4190.
    Ålund, Murielle
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Segami, Carolina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Duke Univ, Dept Biol, Durham, NC USA..
    Zhu, Yishu
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Menon, P. Navaneeth Krishna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ Basel, DUW Zool, Basel, Switzerland..
    Jones, William
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ Debrecen, Dept Evolutionary Zool & Human Biol, Debrecen, Hungary..
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Tracking hybrid viability across life stages in a natural avian contact zone2024In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 78, no 2, p. 267-283Article in journal (Refereed)
    Abstract [en]

    Hybrid inviability is an important post-zygotic reproductive barrier between species, but emerging signs of reduced viability can be difficult to study across the lifespan of natural hybrids. We use a combination of long-term monitoring, extra-pair paternity, and mitochondrial DNA identification in a natural hybrid zone of Ficedula flycatchers to detect emerging signs of intrinsic hybrid inviability across their entire lifespan. We evaluate possible evidence of Darwin's corollary to Haldane's rule, predicting asymmetries in inviability between hybrids resulting from reciprocal crosses, due to incompatible genetic factors with sex-specific inheritance patterns. We found higher hatching failure among mixed-species pairs, possibly indicating early developmental impairments associated with specific parental genetic combinations. Adult hybrids had a higher basal mortality rate than both parental species and different age-specific mortality trajectories. There were signs of differences in age-independent mortality rates between the reciprocal hybrid crosses: hybrids with a pied flycatcher mother experienced slightly increased mortality later in life. Using an exceptional dataset with many natural hybrids tracked across life stages, we provide evidence for several emerging signs of reduced hybrid viability. Incompatibilities between alleles located on autosomes and uniparentally inherited factors such as Z-linked and/or mitochondrial genes are strong candidates underlying intrinsic hybrid dysfunction in this system.

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  • 4191.
    Ålund, Murielle
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Whittington, Emma
    Center for Reproductive Evolution, 248 Life Sciences Complex, Syracuse, NY 13244, USA.
    Backström, Niclas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Borziak, Kirill
    Center for Reproductive Evolution, 248 Life Sciences Complex, Syracuse, NY 13244, USA.
    Jones, Williams
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    McFarlane, S. Eryn
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Mugal, Carina F.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Wang, Mi
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Wheatcroft, David
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Xu, Luohao
    University of Vienna, Austria.
    Ellegren, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Immler, Simone
    School of Biological Sciences, University of East Anglia, Norwich, Norfolk, NR4 7TJ, UK.
    Dorus, Steve
    Center for Reproductive Evolution, 248 Life Sciences Complex, Syracuse, NY 13244, USA.
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Reproductive -omics of a wild avian speciation model unveils candidate genes for gamete interactionManuscript (preprint) (Other academic)
    Abstract [en]

    The complex nature of interspecific interactions contributing to reproductive isolation means that we still know little about their molecular basis. Male reproductive traits are notorious for their fast evolution at the phenotypic and genotypic level, and divergence in components of the ejaculate can lead to incompatibilities between closely related species. Making use of recent advances of molecular tools and the extensive knowledge on the biology and ecology of young sister species, here the pied (Ficedula hypoleuca) and collared flycatcher (F. albicollis), allows the identification of candidate phenotypes and the underlying genotypes maintaining species boundaries. Pied flycatcher females can avoid costly production of sterile hybrids when mated to collared flycatchers by cryptically favouring conspecific sperm. Here, we describe the testes transcriptome and sperm proteome of both species, confirm the complexity of avian sperm development and functions and identify several candidate genes for interactions between sperm and the female reproductive tract, using multiple independent measures of divergence between the species. We show that divergence at the transcriptional and translational levels can potentially lead to the evolution of reproductive incompatibilities despite low levels of sequence divergence, and suggest that integrating several -omics techniques with knowledge of the biology of naturally hybridizing species will greatly improve our understanding of the molecular basis of speciation in the near future. 

  • 4192.
    Ålund née Podevin, Murielle
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sex, Sperm and Speciation: On sexual selection and fertility in hybridizing flycatchers2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Sexual reproduction entails complex co-evolution between the sexes, necessary for successful fertilization, ensuring individual and population-level fitness. Interfertility is the main criterion for species definition and understanding speciation requires detailed studies of reproductive barriers. However, many studies on reproductive barriers are constrained to infer evolutionary processes from patterns. In this thesis, I focus on a hybrid zone between collared and pied flycatchers (Ficedula albicollis and hypoleuca) on the island of Öland, and a trait that is essential for fertilization: sperm. Long-term monitoring of these species, combined with recent advances in molecular tools, allow me to study how complex on-going intersexual and interspecific interactions influence reproductive isolation in this young hybrid zone. I start by exploring the links between pre- and postmating sexual selection within collared flycatchers (paper I and II). I show that secondary sexual characters and indirect mate-choice benefits are tightly linked to physiology (paper I), and that a male’s attractiveness and dominance status dictate which sperm traits are optimal, as a male’s fertilization success depends on an interaction between sperm and display traits (paper II). I then report a source of strong postzygotic isolation between recently diverged collared and pied flycatchers: impaired spermatogenesis resulting in absence of mature sperm cells in hybrid males (paper III). I show however that pied flycatcher females, who are most exposed to hybridization, can mitigate these costs through mechanisms of cryptic female choice impairing heterospecific sperm performance, allowing them to bias paternity towards pure-species offspring (paper IV). Finally, by exploring the testes transcriptomes and sperm proteomes of both species, I highlight the importance of gene and protein regulation mechanisms in facilitating phenotypic divergence between these species (paper V). Thus, my thesis reveals complex interactions between primary and secondary sexual characters in a wild bird and suggests that mechanisms of sexual selection are tightly linked to essential physiological functions. I also show that genetic incompatibilities can evolve rapidly despite low genome-wide levels of divergence but that divergence in regulatory regions and proteins potentially allows fast evolution of molecular mechanisms impairing or preventing costly heterospecific fertilization. 

    List of papers
    1. Sexual selection affects climate adaptation in collared flycatchers
    Open this publication in new window or tab >>Sexual selection affects climate adaptation in collared flycatchers
    2017 (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    The role of sexual selection in climate adaptation is debated. We tested whether sexual selection has the potential to speed up adaptation to thermal conditions in a natural population of collared flycatchers. Based on a three-year cross-fostering experiment, we found that the size of a sexually selected trait predicted offspring metabolic rate: male collared flycatchers with large forehead patches sired offspring with low metabolic rate regardless of the ambient temperature. Thus, there was a stable significant relationship between forehead patch size of genetic fathers and offspring metabolic rate. Nestlings with high metabolic rate experienced a survival advantage when growing under warm temperatures, while the opposite was true in cold environments. Our study shows that females can modulate their offspring’s physiology through mate choice, and that sexual selection can thus affect climate adaptation.

    Keywords
    sexual selection, climate adaptation, resting metabolic rate, Ficedula flycatcher, secondary sexual character, physiology
    National Category
    Evolutionary Biology
    Identifiers
    urn:nbn:se:uu:diva-322788 (URN)
    Available from: 2017-07-30 Created: 2017-07-30 Last updated: 2017-07-30
    2. Revisiting the definition of “sperm quality”: selection on sperm length depends on a male’s attractiveness and dominance in wild collared flycatchers
    Open this publication in new window or tab >>Revisiting the definition of “sperm quality”: selection on sperm length depends on a male’s attractiveness and dominance in wild collared flycatchers
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Dominance over rivals, sexual attractiveness and highly efficient ejaculates are all known to be essential for male fertilization success but the theories of how primary and secondary sexual characters may co-evolve largely remain to be tested. Here, we measure sperm morphology in 131 wild-caught collared flycatchers over a four-year period and investigate the links between male display traits, sperm characteristics and siring success among 425 offspring sired by 71 of these males. We show that the optimal sperm length to attain high relative fertilization success depends on the size of a male’s secondary sexual character. Males with small ornaments sire more offspring in their own nest when they produce long sperm and vice-versa. These results are not compatible with theories based on simple relationships between secondary sexual traits and sperm “quality” but imply that the optimal fertilization strategy (and hence optimal sperm traits) differ between males even in a predominantly socially monogamous population with moderate extra-pair copulation rates. Thus, a better knowledge of the complex chain of behavioural interactions between the sexes and their gametes is needed for a complete understanding of how sexual selection operates in nature.

    Keywords
    sperm morphology, secondary sexual character, mating strategy, fertilization success, Ficedula flycatcher, extra-pair copulation
    National Category
    Evolutionary Biology
    Identifiers
    urn:nbn:se:uu:diva-326808 (URN)
    Available from: 2017-07-30 Created: 2017-07-30 Last updated: 2017-07-30
    3. Low fertility of wild hybrid male flycatchers despite recent divergence
    Open this publication in new window or tab >>Low fertility of wild hybrid male flycatchers despite recent divergence
    2013 (English)In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 9, no 3, article id 20130169Article in journal (Refereed) Published
    Abstract [en]

    Postzygotic isolation may be important for maintaining species boundaries, particularly when premating barriers are incomplete. Little is known about the course of events leading from minor environmental mismatches affecting hybrid fitness to severe genetic incompatibilities causing sterility or inviability. We investigated whether reduced reproductive success of hybrid males was caused by suboptimal sperm traits or by more severe genetic incompatibilities in a hybrid zone of pied (Ficedula hypoleuca) and collared flycatchers (F. albicollis) on the island of Oland, Sweden. About 4 per cent hybridization is observed in this population and all female hybrids are sterile. We found no sperm in the ejaculates of most sampled hybrid males, and sperm with abnormal morphology in two hybrids. Furthermore, none of the hybrids sired any offspring because of high levels of hatching failure and extra-pair paternity in their nests. These results from a natural hybrid zone suggest that the spermatogenesis of hybrid males may become disrupted despite little genetic divergence between the parental species.

    Keywords
    hybrid, sterility-infertility, flycatcher, sperm, postzygotic incompatibility
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:uu:diva-202341 (URN)10.1098/rsbl.2013.0169 (DOI)000318762300035 ()
    Available from: 2013-06-24 Created: 2013-06-24 Last updated: 2017-12-06Bibliographically approved
    4. Females discriminate against heterospecific sperm in a natural hybrid zone
    Open this publication in new window or tab >>Females discriminate against heterospecific sperm in a natural hybrid zone
    Show others...
    2016 (English)In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 70, no 8, p. 1844-1855Article in journal (Refereed) Published
    Abstract [en]

    When hybridization is maladaptive, species-specific mate preferences are selectively favored, but low mate availability may constrain species-assortative pairing. Females paired to heterospecifics may then benefit by copulating with multiple males and subsequently favoring sperm of conspecifics. Whether such mechanisms for biasing paternity toward conspecifics act as important reproductive barriers in socially monogamous vertebrate species remains to be determined. We use a combination of long-term breeding records from a natural hybrid zone between collared and pied flycatchers (Ficedula albicollis and F. hypoleuca), and an in vitro experiment comparing conspecific and heterospecific sperm performance in female reproductive tract fluid, to evaluate the potential significance of female cryptic choice. We show that the females most at risk of hybridizing (pied flycatchers) frequently copulate with multiple males and are able to inhibit heterospecific sperm performance. The negative effect on heterospecific sperm performance was strongest in pied flycatcher females that were most likely to have been previously exposed to collared flycatcher sperm. We thus demonstrate that a reproductive barrier acts after copulation but before fertilization in a socially monogamous vertebrate. While the evolutionary history of this barrier is unknown, our results imply that there is opportunity for it to be accentuated via a reinforcement-like process.

    Keywords
    Cryptic female choice, hybrid zones, postcopulatory prezygotic barriers, reinforcement, speciation, sexual selection
    National Category
    Evolutionary Biology
    Identifiers
    urn:nbn:se:uu:diva-303102 (URN)10.1111/evo.12986 (DOI)000381205700013 ()
    Funder
    Swedish Research Council, 621-2012-3722The Royal Swedish Academy of Sciences
    Available from: 2016-10-05 Created: 2016-09-15 Last updated: 2018-08-10Bibliographically approved
    5. Reproductive -omics of a wild avian speciation model unveils candidate genes for gamete interaction
    Open this publication in new window or tab >>Reproductive -omics of a wild avian speciation model unveils candidate genes for gamete interaction
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    The complex nature of interspecific interactions contributing to reproductive isolation means that we still know little about their molecular basis. Male reproductive traits are notorious for their fast evolution at the phenotypic and genotypic level, and divergence in components of the ejaculate can lead to incompatibilities between closely related species. Making use of recent advances of molecular tools and the extensive knowledge on the biology and ecology of young sister species, here the pied (Ficedula hypoleuca) and collared flycatcher (F. albicollis), allows the identification of candidate phenotypes and the underlying genotypes maintaining species boundaries. Pied flycatcher females can avoid costly production of sterile hybrids when mated to collared flycatchers by cryptically favouring conspecific sperm. Here, we describe the testes transcriptome and sperm proteome of both species, confirm the complexity of avian sperm development and functions and identify several candidate genes for interactions between sperm and the female reproductive tract, using multiple independent measures of divergence between the species. We show that divergence at the transcriptional and translational levels can potentially lead to the evolution of reproductive incompatibilities despite low levels of sequence divergence, and suggest that integrating several -omics techniques with knowledge of the biology of naturally hybridizing species will greatly improve our understanding of the molecular basis of speciation in the near future. 

    Keywords
    Reproductive isolation, cryptic female choice, sperm, proteomics, transcriptomics, Ficedula flycatchers
    National Category
    Evolutionary Biology
    Identifiers
    urn:nbn:se:uu:diva-326809 (URN)
    Available from: 2017-07-30 Created: 2017-07-30 Last updated: 2017-07-30
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  • 4193.
    Ödeen, Anders
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Håstad, Olle
    Department of Anatomy, Physiology and Biochemistry, Swedish University of Agricultural Sciences, S-75007 Uppsala, Sweden..
    The phylogenetic distribution of ultraviolet sensitivity in birds2013In: BMC Evolutionary Biology, E-ISSN 1471-2148, Vol. 13, p. 36-Article in journal (Refereed)
    Abstract [en]

    Background: Colour vision in birds can be categorized into two classes, the ultraviolet (UVS) and violet sensitive (VS). Their phylogenetic distributions have traditionally been regarded as highly conserved. However, the complicated nature of acquiring spectral sensitivities from cone photoreceptors meant that until recently, only a few species had actually been studied. Whether birds are UVS or VS can nowadays be inferred from a wide range of species via genomic sequencing of the UV/violet SWS1 cone opsin gene. Results: We present genomic sequencing results of the SWS1 gene from 21 avian orders. Amino acid residues signifying UV sensitivity are found in the two most important spectral tuning sites 86 and 90 of Pteroclidiformes and Coraciiformes, in addition to the major clades, Palaeognathae, Charadriiformes, Trogoniformes, Psittaciformes and Passeriformes, where they where previously known to occur. We confirm that the presumed UVS-conferring amino acid combination F86, C90 and M93 is common to Palaeognathae and unique to this clade, despite available spectrometric evidence showing the ostrich retina to be VS. Conclusions: By mapping our results together with data from previous studies on a molecular phylogeny we show that avian colour vision shifted between VS and UVS at least 14 times. Single nucleotide substitutions can explain all these shifts. The common ancestor of birds most likely had a VS phenotype. However, the ancestral state of the avian SWS1 opsin's spectral tuning sites cannot be resolved, since the Palaeognathae are F86, C90 while the Neognathae are ancestrally S86, S90. The phylogenetic distribution of UVS and VS colour vision in birds is so complex that inferences of spectral sensitivities from closely related taxa should be used with caution.

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  • 4194.
    Ödeen, Anders
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Håstad, Olle
    Alström, Per
    Evolution of ultraviolet vision in shorebirds (Charadriiformes)2010In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 6, p. 370-374Article in journal (Refereed)
    Abstract [en]

    Diurnal birds belong to one of two classes of colour vision. These are distinguished by the maximum absorbance wavelengths of the SWS1 visual pigment sensitive to violet (VS) and ultraviolet (UVS). Shifts between the classes have been rare events during avian evolution. Gulls (Laridae) are the only shorebirds (Charadriiformes) previously reported to have the UVS type of opsin, but too few species have been sampled to infer that gulls are unique among shorebirds or that Laridae is monomorphic for this trait. We have sequenced the SWS1 opsin gene in a broader sample of species. We confirm that cysteine in the key amino acid position 90, characteristic of the UVS class, has been conserved throughout gull evolution but also that the terns Anous minutus, A. tenuirostris and Gygis alba, and the skimmer Rynchops niger carry this trait. Terns, excluding Anous and Gygis, share the VS conferring serine in position 90 with other shorebirds but it is translated from a codon more similar to that found in UVS shorebirds. The most parsimonious interpretation of these findings, based on a molecular gene tree, is a single VS to UVS shift and a subsequent reversal in one lineage.

  • 4195.
    Ödeen, Anders
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal Ecology.
    Håstad, Olle
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology.
    Alström, Per
    Evolution of ultraviolet vision in the largest avian radiation: the passerines2011In: BMC Evolutionary Biology, E-ISSN 1471-2148, Vol. 11, p. 313-Article in journal (Refereed)
    Abstract [en]

    Background: Interspecific variation in avian colour vision falls into two discrete classes: violet sensitive (VS) and ultraviolet sensitive (UVS). They are characterised by the spectral sensitivity of the most shortwave sensitive of the four single cones, the SWS1, which is seemingly under direct control of as little as one amino acid substitution in the cone opsin protein. Changes in spectral sensitivity of the SWS1 are ecologically important, as they affect the abilities of birds to accurately assess potential mates, find food and minimise visibility of social signals to predators. Still, available data have indicated that shifts between classes are rare, with only four to five independent acquisitions of UV sensitivity in avian evolution. Results: We have classified a large sample of passeriform species as VS or UVS from genomic DNA and mapped the evolution of this character on a passerine phylogeny inferred from published molecular sequence data. Sequencing a small gene fragment has allowed us to trace the trait changing from one stable state to another through the radiation of the passeriform birds. Their ancestor is hypothesised to be UVS. In the subsequent radiation, colour vision changed between UVS and VS at least eight times. Conclusions: The phylogenetic distribution of SWS1 cone opsin types in Passeriformes reveals a much higher degree of complexity in avian colour vision evolution than what was previously indicated from the limited data available. Clades with variation in the colour vision system are nested among clades with a seemingly stable VS or UVS state, providing a rare opportunity to understand how an ecologically important trait under simple genetic control may co-evolve with, and be stabilised by, associated traits in a character complex.

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  • 4196.
    Ödeen, Anders
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal Ecology.
    Pruett-Jones, Stephen
    Driskell, Amy C.
    Armenta, Jessica K.
    Håstad, Olle
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Multiple shifts between violet and ultraviolet vision in a family of passerine birds with associated changes in plumage coloration2012In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 279, no 1732, p. 1269-1276Article in journal (Refereed)
    Abstract [en]

    Colour vision in diurnal birds falls into two discrete classes, signified by the spectral sensitivity of the violet- (VS) or ultraviolet-sensitive (UVS) short wavelength-sensitive type 1 (SWS1) single cone. Shifts between sensitivity classes are rare; three or four are believed to have happened in the course of avian evolution, one forming UVS higher passerines. Such shifts probably affect the expression of shortwave-dominated plumage signals. We have used genomic DNA sequencing to determine VS or UVS affinity in fairy-wrens and allies, Maluridae, a large passerine family basal to the known UVS taxa. We have also spectrophotometrically analysed male plumage coloration as perceived by the VS and UVS vision systems. Contrary to any other investigated avian genus, Malurus (fairy-wrens) contains species with amino acid residues typical of either VS or UVS cone opsins. Three bowerbird species (Ptilonorhynchidae) sequenced for outgroup comparison carry VS opsin genes. Phylogenetic reconstructions render one UVS gain followed by one or more losses as the most plausible evolutionary scenario. The evolution of avian ultraviolet sensitivity is hence more complex, as a single shift no longer explains its distribution in Passeriformes. Character correlation analysis proposes that UVS vision is associated with shortwave-reflecting plumage, which is widespread in Maluridae.

  • 4197.
    Öquist, Mats G.
    et al.
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU).
    Bishop, Kevin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Uppsala Centre for Sustainable Development, CSD Uppsala.
    Grelle, Achim
    Department of Ecology, Swedish University of Agricultural Sciences (SLU).
    Klemedtsson, Leif
    Department of Earth Sciences, Gothenburg University.
    Köhler, Stephan J.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU).
    Laudon, Hjalmar
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU).
    Lindroth, Anders
    Department of Physical Geography and Ecosystem Analysis, Lund University.
    Ottosson Löfvenius, Mikaell
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU).
    Wallin, Marcus B.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Nilsson, Mats B.
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU).
    The full annual carbon balance of boreal forestsis highly sensitive to precipitation2014In: Environmental Science and Technology Letters, ISSN 2328-8930, Vol. 1, no 7, p. 315-319Article in journal (Refereed)
    Abstract [en]

    The boreal forest carbon balance is predicted to be particularly sensitive to climate change. Carbon balance estimates of these biomes stem mainly from eddy-covariance measurements of net ecosystem exchange (NEE). However, a full net ecosystem carbon balance (NECB) must include the lateral carbon export (LCE) through discharge. We show that annual LCE at a boreal forest site ranged from 4 to 28%, averaging 11% (standard deviation of 8%), of annual NEE over 13 years. Annual LCE and NEE are strongly anticorrelated; years with weak NEE coincide with high LCE. The decreased NEE in response to increased precipitation is caused by a reduction in the amount of incoming radiation caused by clouds. If our finding is also valid for other sites, it implies that increased precipitation at high latitudes may shift forest NECB in large areas of the boreal biome. Our results call for future analysis of this dual effect of precipitation on NEE and LCE.

  • 4198.
    Örjes, Elliot
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Does size matter?: A study on pollen size distribution and pollen viability in Silene latifolia and S. dioica2021Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Pollen size dimorphism, i.e., when a plant produces more than one size of pollen, has been observed in several plant families but the underlying mechanisms have rarely been discussed. One of the hypotheses is that the smaller pollen produced by individuals with bimodal pollen size distributions are dead or non-viable. In this thesis, I use the campions Silene latifolia and S. dioica to study pollen dimorphism and pollen viability. To study the pollen dimorphism, pollen was collected from eight S. latifolia populations grown in a greenhouse and three wild S. dioica populations. The S. latifolia populations originated from France, Great Britain, Germany, Poland, Switzerland, Russia, Belgium and Romania while the S. dioica populations all came from around Uppsala. The pollen from each individual was analysed under a microscope to determine if the individual produced uni-/bimodal pollen. To test pollen viability, an in vitro germination experiment was conducted, using pollen tube length as a proxy for viability. Individuals with bimodal pollen size distributions were found in almost all populations of both species with frequencies ranging between 10 - 66%. Among the individuals with unimodal pollen size distributions, it was more common to produce larger pollen but, in some populations, there were unimodal individuals producing small pollen. The presence of individuals with different unimodal pollen size distributions as well as with bimodal pollen size distributions in the same population suggests that pollen size dimorphism might be governed by segregating alleles at one or several loci, contradicting earlier studies suggesting meiotic drive. In the viability test, the smaller pollen grew a longer tube and thus might have a higher pollen tube growth rate (PTGR) than the larger pollen. This, together with other studies showing that a high PTGR correlates with high siring success, indicates that small pollen might be highly viable. The smaller pollen may have higher pollen tube growth rate and should therefore have a higher siring success as it may be able to reach the ovules quicker and thus be more common in populations but is a rare phenotype. This might be due to large pollen being superior in other ways.

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  • 4199.
    Östman, Örjan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology.
    Abundance-occupancy relationships in metapopulations: examples of rock pool Daphnia2011In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 165, no 3, p. 687-697Article in journal (Refereed)
    Abstract [en]

    Intraspecific positive relationships between abundance and occupancy are observed for many species, suggesting that the same processes drive local and regional species dynamics. Two main groups of mechanisms explain this relationship: spatiotemporal variation in local population growth rates due to variation in habitat quality, or dispersal effects that increase occupancy of a species when locally abundant. Several studies show that spatiotemporal variation in population growth rates causes positive abundance-occupancy relationships, but few have shown dispersal effects. It is believed that such effects should be more evident for species whose dispersal is limited, e.g. metapopulations, but those studies are limited. This study investigates abundance-occupancy relationships in three Daphnia metapopulations in rock pools and the degree to which dispersal or habitat quality affect their local abundances and occurrence. Daphnia longispina and Daphnia magna showed positive abundance-occupancy relationships, but not Daphnia pulex. No single ecological factor could explain the abundance-occupancy relationships of any given species. Instead, dispersal processes and rock pool quality (mainly salinity and depth) seem to act together to shape the abundance-occupancy relationships. Such a conclusion is also supported by an immigration experiment in natural rock pools. This study suggests that although positive abundance-occupancy relationships may be commonly found for metapopulations, both dispersal processes and variation in habitat quality can be factors determining the abundance-occupancy relationship of metapopulations experiencing habitat heterogeneity.

  • 4200.
    Östman, Örjan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology.
    Interspecific competition affects genetic structure but not genetic diversity of Daphnia magna2011In: Ecosphere, ISSN 2150-8925, E-ISSN 2150-8925, Vol. 2, no 3, article id UNSP 34Article in journal (Refereed)
    Abstract [en]

    There are multiple forces structuring the genetic diversity of populations, and numerous studies have investigated the effects of the environment, space and stochastic processes. The effect of variation in interspecific interactions on genetic diversity and structure has rarely been assessed. Here, in a mescosm experiment, I studied clonal diversity and composition of the water-flea Daphnia magna in presence and absence of the sympatric interspecific competitors D. longispina and D. pulex. The results showed little effect of interspecific competition per se on clonal diversity of D. magna. Instead, the observed minimum population size was the most important factor for clonal diversity. But variation in interspecific competition had an effect on the clonal composition, and the presence of both interspecific competitors changed the clonal composition of D. magna. Thus, I conclude that interspecific competition had little effect on genetic diversity of D. magna but an evident effect on the genotypic composition, which may be important for the genetic diversity and structure on larger spatio-temporal scales.

8182838485 4151 - 4200 of 4206
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