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  • 201.
    Alatalo, Juha M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Little, Chelsea J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Jagerbrand, Annika K.
    Molau, Ulf
    Dominance hierarchies, diversity and species richness of vascular plants in an alpine meadow: contrasting short and medium term responses to simulated global change2014In: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, Vol. 2, p. e406-Article in journal (Refereed)
    Abstract [en]

    We studied the impact of simulated global change on a high alpine meadow plant community. Specifically, we examined whether short-term (5 years) responses are good predictors for medium-term (7 years) changes in the system by applying a factorial warming and nutrient manipulation to 20 plots in Latnjajaure, subarctic Sweden. Seven years of experimental warming and nutrient enhancement caused dramatic shifts in dominance hierarchies in response to the nutrient and the combined warming and nutrient enhancement treatments. Dominance hierarchies in the meadow moved from a community being dominated by cushion plants, deciduous, and evergreen shrubs to a community being dominated by grasses, sedges, and forbs. Short-termresponses were shown to be inconsistent in their ability to predict medium-term responses for most functional groups, however, grasses showed a consistent and very substantial increase in response to nutrient addition over the seven years. The non-linear responses over time point out the importance of longer-term studies with repeated measurements to be able to better predict future changes. Forecasted changes to temperature and nutrient availability have implications for trophic interactions, and may ultimately influence the access to and palatability of the forage for grazers. Depending on what anthropogenic change will be most pronounced in the future (increase in nutrient deposits, warming, or a combination of them both), different shifts in community dominance hierarchies may occur. Generally, this study supports the productivity-diversity relationship found across arctic habitats, with community diversity peaking in mid-productivity systems and degrading as nutrient availability increases further. This is likely due the increasing competition in plant-plant interactions and the shifting dominance structure with grasses taking over the experimental plots, suggesting that global change could have high costs to biodiversity in the Arctic.

  • 202.
    Alatalo, Juha M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Little, Chelsea J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Jagerbrand, Annika K.
    Molau, Ulf
    Vascular plant abundance and diversity in an alpine heath under observed and simulated global change2015In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, article id 10197Article in journal (Refereed)
    Abstract [en]

    Global change is predicted to cause shifts in species distributions and biodiversity in arctic tundra. We applied factorial warming and nutrient manipulation to a nutrient and species poor alpine/arctic heath community for seven years. Vascular plant abundance in control plots increased by 31%. There were also notable changes in cover in the nutrient and combined nutrient and warming treatments, with deciduous and evergreen shrubs declining, grasses overgrowing these plots. Sedge abundance initially increased significantly with nutrient amendment and then declined, going below initial values in the combined nutrient and warming treatment. Nutrient addition resulted in a change in dominance hierarchy from deciduous shrubs to grasses. We found significant declines in vascular plant diversity and evenness in the warming treatment and a decline in diversity in the combined warming and nutrient addition treatment, while nutrient addition caused a decline in species richness. The results give some experimental support that species poor plant communities with low diversity may be more vulnerable to loss of species diversity than communities with higher initial diversity. The projected increase in nutrient deposition and warming may therefore have negative impacts on ecosystem processes, functioning and services due to loss of species diversity in an already impoverished environment.

  • 203.
    Alatalo, Juha M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ostapenko, Oksana V.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    The Swedish system: The image cracking when taking a closer look2014In: Geoforum, ISSN 0016-7185, E-ISSN 1872-9398, Vol. 53, p. 82-83Article, review/survey (Refereed)
    Abstract [en]

    Sweden has a high international profile regarding social issues and projects an image as one of the best countries in the world in terms of social indicators. Here we argue for a revised view as the reality is that Swedish system is very segregated, particularly in terms of (1) relative lack of women in positions of high influence, (2) it is the worst country in the EU28 regarding long-term unemployment for people born outside the country, and (3) it has a education system that after a number of reforms is involved in a "race towards the bottom" to profit from students. At the same time Sweden undervalues foreign academic qualifications and getting work largely depends on "who you know", not "what you know".

  • 204. Alatalo, R. V.
    et al.
    Eriksson, D.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Larsson, K.
    EXPLOITATION COMPETITION INFLUENCES THE USE OF FORAGING SITES BY TITS - EXPERIMENTAL-EVIDENCE1987In: Ecology, Vol. 68, no 2, p. 284-290Article in journal (Refereed)
  • 205. Alatalo, R. V.
    et al.
    Eriksson, D.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Larsson, K.
    Exploitation competition influences the use of foraging sites by tits: experimental evidence.1987In: Ecology, Vol. 68, no 2, p. 284-290Article in journal (Refereed)
  • 206. Alatalo, R. V.
    et al.
    Eriksson, D.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    HYBRIDIZATION BETWEEN PIED AND COLLARED FLYCATCHERS - SEXUAL SELECTION AND SPECIATION THEORY1990In: Journal of Evolutionary Biology, Vol. 3, no 5-6, p. 375-389Article in journal (Refereed)
  • 207. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    GENETIC COMPONENT OF MORPHOLOGICAL-DIFFERENTIATION IN COAL TITS UNDER COMPETITIVE RELEASE1988In: Evolution, Vol. 42, no 1, p. 200-203Article in journal (Refereed)
  • 208. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Linden, M.
    Lundberg, A.
    INTERSPECIFIC COMPETITION AND NICHE SHIFTS IN TITS AND THE GOLDCREST - AN EXPERIMENT1985In: Journal of Animal Ecology, Vol. 54, no 3, p. 977-984Article in journal (Refereed)
  • 209. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Linden, M.
    Lundberg, A.
    Interspecific competition and niche shifts in tits and the goldcrest: an experiment.1985In: Journal of Animal Ecology, Vol. 54, no 3, p. 977-984Article in journal (Refereed)
  • 210. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    Breeding success and hybridization of collared flycatcher Ficedula albicollis, and pied flycatcher, Ficedula hypoleuca on Oland 19811982In: Calidris, Vol. 11, no 2, p. 103-108Article in journal (Refereed)
  • 211. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    ( Breeding success and hybridization of collared flycatcher, Ficedula albicollis, and pied flycatcher, Ficedula hypoleuca, on Oland 1981). | Hackningsframgang och forekomst av halsbandsflugsnappare Ficedula albicollis, svartvit flugsnappare Ficedula hypoleuca samt blandpar pa Oland 1981.1982In: Calidris, Vol. 2, no 82, p. 103-108Article in journal (Refereed)
  • 212. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    DO FEMALES PREFER OLDER MALES IN POLYGYNOUS BIRD SPECIES1986In: American Naturalist, Vol. 127, no 2, p. 241-245Article in journal (Refereed)
  • 213. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    EXTRA-PAIR PATERNITY AND HERITABILITY ESTIMATES OF TARSUS LENGTH IN PIED AND COLLARED FLYCATCHERS1989In: Oikos, Vol. 56, no 1, p. 54-58Article in journal (Refereed)
  • 214. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    Extra-pair paternity and heritability estimates of tarsus length in pied and collared flycatchers1989In: Oikos, Vol. 56, no 1, p. 54-58Article in journal (Refereed)
  • 215. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    High frequency of cuckoldry in pied and collared flycatchers.1984In: Oikos, Vol. 42, no 1, p. 41-47Article in journal (Refereed)
  • 216. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    Hybridization and breeding success of collared and pied flycatchers on the island of Gotland.1982In: Auk, Vol. 99, no 2, p. 285-291Article in journal (Refereed)
  • 217. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    HYBRIDIZATION AND BREEDING SUCCESS OF COLLARED AND PIED FLYCATCHERS ON THE ISLAND OF GOTLAND1982In: Auk, Vol. 99, no 2, p. 285-291Article in journal (Refereed)
  • 218. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    Interspecific competition and niche changes in tits ( Parus spp.): evaluation of nonexperimental data.1986In: American Naturalist, Vol. 127, no 6, p. 819-834Article in journal (Refereed)
  • 219. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    INTERSPECIFIC COMPETITION AND NICHE CHANGES IN TITS (PARUS SPP) - EVALUATION OF NONEXPERIMENTAL DATA1986In: American Naturalist, Vol. 127, no 6, p. 819-834Article in journal (Refereed)
  • 220. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    MALE COLORATION AND SPECIES RECOGNITION IN SYMPATRIC FLYCATCHERS1994In: Proceedings of the Royal Society B-Biological Sciences, Vol. 256, no 1346, p. 113-118Article in journal (Refereed)
  • 221. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    PHENOTYPIC SELECTION ON HERITABLE SIZE TRAITS - ENVIRONMENTAL VARIANCE AND GENETIC RESPONSE1990In: American Naturalist, Vol. 135, no 3, p. 464-471Article in journal (Refereed)
  • 222. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    WHY DO YOUNG PASSERINE BIRDS HAVE SHORTER WINGS THAN OLDER BIRDS1984In: Ibis, Vol. 126, no 3, p. 410-415Article in journal (Refereed)
  • 223. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    Ulfstrand, S.
    HABITAT SHIFT OF THE WILLOW TIT PARUS MONTANUS IN THE ABSENCE OF THE MARSH TIT PARUS PALUSTRIS1985In: Ornis Scandinavica, Vol. 16, no 2, p. 121-128Article in journal (Refereed)
  • 224. Alatalo, R. V.
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Lundberg, A.
    Ulfstrand, S.
    Habitat shift of the willow tit Parus montanus in the absence of the marsh tit Parus palustris.1985In: Ornis Scandinavica, Vol. 16, no 2, p. 121-128Article in journal (Refereed)
  • 225.
    Alatalo, Rauno V
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Lundberg, Arne
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Sundberg, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Can Female Preference Explain Sexual Dichromatism In The Pied Flycatcher, Ficedula-Hypoleuca1990In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 39, p. 244-252Article in journal (Refereed)
    Abstract [en]

    How important female choice is for the evolution of male secondary sexual characteristics is controversial. Two field and one laboratory experiment, using the pied flycatcher, were performed to test the female choice aspect of sexual selection. In addition, non-manipulative data from 5 years are presented. The observational data suggest a slight preference for dark males by females but in field experiments in which males had territories at random sites (i.e. they did not choose a territory) or the colour of concurrently arriving males was altered, there was no preference for darker ones. Similarly, oestradiol-treated females did not prefer black or brown males in the laboratory. Thus, there is little support for the idea that female choice has been an important mechanism in the evolution of sexual dichromatism in the pied flycatcher.

  • 226.
    Alavioon, Ghazal
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Haploid selection in animals: Exploring the fitness consequences and underlying mechanisms2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    A consequence of sexual reproduction in eukaryotes is the evolution of a biphasic life cycle with alternating diploid and haploid gametic phases. While our focus in evolutionary biology is on selection during the diploid phase, we know relatively little about selection occurring during the haploid gametic stage. This is particularly true in predominantly diploid animals, where gene expression and hence selection have long been thought to be absent in haploid cells like gametes and particularly sperm. During my PhD, I tested the idea of selection during the haploid gametic phase using zebrafish Danio rario as a study species. I combined a large-scale selection experiment over three generations with fitness assays and next-generation sequencing to assess the importance of haploid selection. We measured offspring fitness in all three generations.  In addition, we compared gene expression in brain and testes of F1 and F3 adult male from each treatment by RNA sequencing. We found that offspring sired by longer-lived sperm showed higher survival rate and higher early- and late-life reproductive fitness compared to offspring sired by shorter-lived sperm. We also found differentially expressed genes between the two treatments with functions in metabolic and developmental pathways. These findings suggest that the observed fitness differences to be caused by small expression changes in many basic genes. We also tested for a genetic underpinning of the selected sperm phenotypes and identified allelic differences across the entire genome. Finally, we investigated the additive genetic component and parental effect of different sperm phenotypes. We found generally low additive genetic variation and high parental effects on sperm performance traits. In conclusion, this thesis provides evidence that the phenotypic variation among intact fertile sperm within an ejaculate affects offspring fitness throughout life and provides a clear link between sperm phenotype and offspring fitness and between sperm phenotype and sperm genotype.

    List of papers
    1. Haploid selection within a single ejaculate increases offspring fitness
    Open this publication in new window or tab >>Haploid selection within a single ejaculate increases offspring fitness
    Show others...
    2017 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, no 30, p. 8053-8058Article in journal (Refereed) Published
    Abstract [en]

    An inescapable consequence of sex in eukaryotes is the evolution of a biphasic life cycle with alternating diploid and haploid phases. The occurrence of selection during the haploid phase can have far-reaching consequences for fundamental evolutionary processes including the rate of adaptation, the extent of inbreeding depression, and the load of deleterious mutations, as well as for applied research into fertilization technology. Although haploid selection is well established in plants, current dogma assumes that in animals, intact fertile sperm within a single ejaculate are equivalent at siring viable offspring. Using the zebrafish Danio rerio, we show that selection on phenotypic variation among intact fertile sperm within an ejaculate affects offspring fitness. Longer-lived sperm sired embryos with increased survival and a reduced number of apoptotic cells, and adult male offspring exhibited higher fitness. The effect on embryo viability was carried over into the second generation without further selection and was equally strong in both sexes. Sperm pools selected by motile phenotypes differed genetically at numerous sites throughout the genome. Our findings clearly link within-ejaculate variation in sperm phenotype to offspring fitness and sperm genotype in a vertebrate and have major implications for adaptive evolution.

    National Category
    Evolutionary Biology
    Identifiers
    urn:nbn:se:uu:diva-320335 (URN)10.1073/pnas.1705601114 (DOI)000406189900080 ()28698378 (PubMedID)
    Funder
    Swedish Research CouncilEU, European Research Council
    Available from: 2017-04-19 Created: 2017-04-19 Last updated: 2018-05-07Bibliographically approved
    2. Within-ejaculate selection for sperm longevity reduces male reproductive ageing
    Open this publication in new window or tab >>Within-ejaculate selection for sperm longevity reduces male reproductive ageing
    Show others...
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Males produce numerous sperm in the single ejaculate that greatly outnumber their potential egg targets. Recent studies found that phenotypic variation among sperm in the single ejaculate of a male reflects the phenotype and the genotype of the resulting offspring. Specifically, within-ejaculate sperm selection (WESS) for sperm longevity increased the performance of the resulting offspring in several key life-history traits in early-life. Because increased early-life reproductive performance often correlates with rapid ageing, it is possible that WESS increases early-life fitness at the cost of accelerated senescence. Alternatively, WESS can improve offspring quality throughout the life cycle, including reduced age-specific deterioration. We found that WESS for sperm longevity reduced age-specific deterioration of male fertility and embryo survival, while there is no effect on fertilization success. Remarkably, we found opposing effect of WESS on female fecundity, where selection for sperm longevity resulted in increased early-life performance followed by a slow decline, while unselected controls started low but increased their fecundity with age. Intriguingly, WESS also reduced the age-specific decline in fertilization success in females, suggesting that selection for sperm longevity improves at least some aspects of female reproductive ageing. These results demonstrate that within-ejaculate variation in sperm phenotype contributes to individual variation in animal life histories in the two sexes and have important implications for assisted fertilization programs in livestock and humans. 

    Keywords
    Ageing, Reproductive Success, Sperm Selection, Sperm Competition, Senescence
    National Category
    Evolutionary Biology
    Research subject
    Biology with specialization in Evolutionary Genetics
    Identifiers
    urn:nbn:se:uu:diva-350186 (URN)
    Available from: 2018-05-07 Created: 2018-05-07 Last updated: 2018-05-07
    3. The fitness consequences of selection among sperm within an ejaculate across generations
    Open this publication in new window or tab >>The fitness consequences of selection among sperm within an ejaculate across generations
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    The evolution of a biphasic life cycle with alternating diploid and haploid phases is a necessary consequence of sexual reproduction in eukaryotes. Selection in each of the phases may have far reaching consequences for many evolutionary processes. While our focus in evolutionary biology lies mainly on selection during the diploid phase, we know relatively little about the role and consequences of selection occurring during the haploid gametic stage. This is particularly true in predominantly diploid animals where the haploid gametic phase is very short. To test the importance of haploid selection in animals, we performed a large-scale selection experiment with selection acting on haploid sperm. We selected on sperm longevity within an ejaculate and tested the effects of such selection over three generation. We performed fitness assays for every generation and found that offspring sired by longer-lived sperm generally exhibit higher fitness from early development into adulthood compared to offspring sired by their shorter-lived sibling sperm in all three generations. These fitness effects were carried over into the second generation without further selection in all three generations. Moreover, using RNA sequencing, we assessed differences in tissue specific gene expression between the offspring sired by the two sperm phenotypes in generation F1 and F3. The transcriptomes in both tissues differed significantly between the two treatments. Many very basic housekeeping genes involved in metabolism and development showed small differences in expression in both tissues. Our study provides solid evidence for the far-reaching consequences of selection on different sperm within a single ejaculate in three consecutive generations, and offers exciting new insights into the possible underlying mechanisms. Our results further highlight the importance of selection at the haploid gametic stages for fundamental evolutionary processes and assisted fertilization technologies.

    Keywords
    Haploid selection, sperm selection, offspring fitness, gene expression
    National Category
    Evolutionary Biology
    Research subject
    Biology with specialization in Evolutionary Genetics
    Identifiers
    urn:nbn:se:uu:diva-350190 (URN)
    Available from: 2018-05-07 Created: 2018-05-07 Last updated: 2018-05-07
    4. Sperm performance traits exhibit low additive genetic component and strong parental effects in external fertilizer
    Open this publication in new window or tab >>Sperm performance traits exhibit low additive genetic component and strong parental effects in external fertilizer
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Despite their key role in determining reproductive success and with that Darwinian fitness, the heritability and underlying additive genetic variance of reproductive traits is still not fully understood. While some traits show relatively high genetic variance, others show very low genetic variance, which is particularly true for complex non-morphological traits. In line with these general patterns, morphological sperm traits show surprisingly high heritability, whereas heritability reported for sperm quality and performance traits generally is lower. A possible explanation for this is the general notion that more fitness related traits show lower levels of additive genetic variance and heritability. We investigated the additive genetic variance and heritability of sperm swimming velocity, the percentage of motile sperm, sperm concentration in the ejaculate and sperm longevity in the externally fertilizing zebrafish Danio rerio. All sperm traits showed low but significant additive genetic variance and high parental components. While the additive genetic variance was significant it was lower than reported in many other studies. A possible explanation for this is that in externally fertilizing species, sperm traits are the prime determinant of fertilization success and high plasticity is crucial for swift adaptations to changes in the environmental conditions such as competition but also water temperature and currents. Given that this is the first study looking into the heritability of sperm traits in an external fertilizer it will be interesting to understand, whether this is true for other externally fertilizing species and taxa.

    Keywords
    additive genetic, parental effect, sperm traits, reproduction
    National Category
    Evolutionary Biology
    Research subject
    Biology with specialization in Evolutionary Genetics
    Identifiers
    urn:nbn:se:uu:diva-350191 (URN)
    Available from: 2018-05-07 Created: 2018-05-07 Last updated: 2018-06-01
  • 227.
    Alavioon, Ghazal
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Baños-Villalba, Adrian
    University Pablo de Olavide, Ctra.
    Schielzeth, Holger
    Friedrich Schiller University Jena.
    Immler, Simone
    University of East Anglia.
    Sperm performance traits exhibit low additive genetic component and strong parental effects in external fertilizerManuscript (preprint) (Other academic)
    Abstract [en]

    Despite their key role in determining reproductive success and with that Darwinian fitness, the heritability and underlying additive genetic variance of reproductive traits is still not fully understood. While some traits show relatively high genetic variance, others show very low genetic variance, which is particularly true for complex non-morphological traits. In line with these general patterns, morphological sperm traits show surprisingly high heritability, whereas heritability reported for sperm quality and performance traits generally is lower. A possible explanation for this is the general notion that more fitness related traits show lower levels of additive genetic variance and heritability. We investigated the additive genetic variance and heritability of sperm swimming velocity, the percentage of motile sperm, sperm concentration in the ejaculate and sperm longevity in the externally fertilizing zebrafish Danio rerio. All sperm traits showed low but significant additive genetic variance and high parental components. While the additive genetic variance was significant it was lower than reported in many other studies. A possible explanation for this is that in externally fertilizing species, sperm traits are the prime determinant of fertilization success and high plasticity is crucial for swift adaptations to changes in the environmental conditions such as competition but also water temperature and currents. Given that this is the first study looking into the heritability of sperm traits in an external fertilizer it will be interesting to understand, whether this is true for other externally fertilizing species and taxa.

  • 228.
    Alavioon, Ghazal
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Cabrera, Andrea
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    LeChatelier, Magali
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Maklakov, Alexei A.
    University of East Anglia.
    Immler, Simone
    University of East Anglia.
    Within-ejaculate selection for sperm longevity reduces male reproductive ageingManuscript (preprint) (Other academic)
    Abstract [en]

    Males produce numerous sperm in the single ejaculate that greatly outnumber their potential egg targets. Recent studies found that phenotypic variation among sperm in the single ejaculate of a male reflects the phenotype and the genotype of the resulting offspring. Specifically, within-ejaculate sperm selection (WESS) for sperm longevity increased the performance of the resulting offspring in several key life-history traits in early-life. Because increased early-life reproductive performance often correlates with rapid ageing, it is possible that WESS increases early-life fitness at the cost of accelerated senescence. Alternatively, WESS can improve offspring quality throughout the life cycle, including reduced age-specific deterioration. We found that WESS for sperm longevity reduced age-specific deterioration of male fertility and embryo survival, while there is no effect on fertilization success. Remarkably, we found opposing effect of WESS on female fecundity, where selection for sperm longevity resulted in increased early-life performance followed by a slow decline, while unselected controls started low but increased their fecundity with age. Intriguingly, WESS also reduced the age-specific decline in fertilization success in females, suggesting that selection for sperm longevity improves at least some aspects of female reproductive ageing. These results demonstrate that within-ejaculate variation in sperm phenotype contributes to individual variation in animal life histories in the two sexes and have important implications for assisted fertilization programs in livestock and humans. 

  • 229.
    Alavioon, Ghazal
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Garcia, Andrea Cabrera
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    LeChatelier, Magali
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Maklakov, Alex A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ East Anglia, Sch Biol Sci, Norwich Res Pk, Norwich, Norfolk, England.
    Immler, Simone
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology. Univ East Anglia, Sch Biol Sci, Norwich Res Pk, Norwich, Norfolk, England.
    Selection for longer lived sperm within ejaculate reduces reproductive ageing in offspring2019In: EVOLUTION LETTERS, ISSN 2056-3744, Vol. 3, no 2, p. 198-206Article in journal (Refereed)
    Abstract [en]

    Males produce numerous sperm in a single ejaculate that greatly outnumber their potential egg targets. Recent studies found that phenotypic and genotypic variation among sperm in a single ejaculate of a male affects the fitness and performance of the resulting offspring. Specifically, within-ejaculate sperm selection for sperm longevity increased the performance of the resulting offspring in several key life-history traits in early life. Because increased early-life reproductive performance often correlates with rapid ageing, it is possible that within-ejaculate sperm selection increases early-life fitness at the cost of accelerated senescence. Alternatively, within-ejaculate sperm selection could improve offspring quality throughout the life cycle, including reduced age-specific deterioration. We tested the two alternative hypotheses in an experimental setup using zebrafish Danio rerio. We found that within-ejaculate sperm selection for sperm longevity reduced age-specific deterioration of fecundity and offspring survival but had no effect on fertilization success in males. Remarkably, we found an opposing effect of within-ejaculate sperm selection on female fecundity, where selection for sperm longevity resulted in increased early-life performance followed by a slow decline, while females sired by unselected sperm started low but increased their fecundity with age. Intriguingly, within-ejaculate sperm selection also reduced the age-specific decline in fertilization success in females, suggesting that selection for sperm longevity improves at least some aspects of female reproductive ageing. These results demonstrate that within-ejaculate variation in sperm phenotype contributes to individual variation in animal life histories in the two sexes and may have important implications for assisted fertilization programs in livestock and humans.

  • 230.
    Alavioon, Ghazal
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Hotzy, Cosima
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Nakhro, Khriezhanuo
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Rudolf, Sandra
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Scofield, Douglas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Zajitschek, Susanne
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology. Spanish Natl Res Council, Donana Biol Stn, Seville 41092, Spain.
    Maklakov, Alex A
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ East Anglia, Sch Biol Sci, Norwich NR4 7TJ, Norfolk, England.
    Immler, Simone
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology. Univ East Anglia, Sch Biol Sci, Norwich NR4 7TJ, Norfolk, England.
    Haploid selection within a single ejaculate increases offspring fitness2017In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, no 30, p. 8053-8058Article in journal (Refereed)
    Abstract [en]

    An inescapable consequence of sex in eukaryotes is the evolution of a biphasic life cycle with alternating diploid and haploid phases. The occurrence of selection during the haploid phase can have far-reaching consequences for fundamental evolutionary processes including the rate of adaptation, the extent of inbreeding depression, and the load of deleterious mutations, as well as for applied research into fertilization technology. Although haploid selection is well established in plants, current dogma assumes that in animals, intact fertile sperm within a single ejaculate are equivalent at siring viable offspring. Using the zebrafish Danio rerio, we show that selection on phenotypic variation among intact fertile sperm within an ejaculate affects offspring fitness. Longer-lived sperm sired embryos with increased survival and a reduced number of apoptotic cells, and adult male offspring exhibited higher fitness. The effect on embryo viability was carried over into the second generation without further selection and was equally strong in both sexes. Sperm pools selected by motile phenotypes differed genetically at numerous sites throughout the genome. Our findings clearly link within-ejaculate variation in sperm phenotype to offspring fitness and sperm genotype in a vertebrate and have major implications for adaptive evolution.

  • 231.
    Alavioon, Ghazal
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Roy M, Francis
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Wyszkowska, Julia
    Jagiellonian University.
    Immler, Simone
    University of East Anglia.
    The fitness consequences of selection among sperm within an ejaculate across generationsManuscript (preprint) (Other academic)
    Abstract [en]

    The evolution of a biphasic life cycle with alternating diploid and haploid phases is a necessary consequence of sexual reproduction in eukaryotes. Selection in each of the phases may have far reaching consequences for many evolutionary processes. While our focus in evolutionary biology lies mainly on selection during the diploid phase, we know relatively little about the role and consequences of selection occurring during the haploid gametic stage. This is particularly true in predominantly diploid animals where the haploid gametic phase is very short. To test the importance of haploid selection in animals, we performed a large-scale selection experiment with selection acting on haploid sperm. We selected on sperm longevity within an ejaculate and tested the effects of such selection over three generation. We performed fitness assays for every generation and found that offspring sired by longer-lived sperm generally exhibit higher fitness from early development into adulthood compared to offspring sired by their shorter-lived sibling sperm in all three generations. These fitness effects were carried over into the second generation without further selection in all three generations. Moreover, using RNA sequencing, we assessed differences in tissue specific gene expression between the offspring sired by the two sperm phenotypes in generation F1 and F3. The transcriptomes in both tissues differed significantly between the two treatments. Many very basic housekeeping genes involved in metabolism and development showed small differences in expression in both tissues. Our study provides solid evidence for the far-reaching consequences of selection on different sperm within a single ejaculate in three consecutive generations, and offers exciting new insights into the possible underlying mechanisms. Our results further highlight the importance of selection at the haploid gametic stages for fundamental evolutionary processes and assisted fertilization technologies.

  • 232. Albach, Dirk
    et al.
    Meudt, Heidi
    Oxelman, Bengt
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Department of Evolution, Genomics and Systematics. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Department of Evolution, Genomics and Systematics, Systematic Botany. Systematisk Botanik.
    Piecing together the "new" Plantaginaceae.2005In: American Journal of Botany, Vol. 92, p. 297-315Article in journal (Refereed)
  • 233. Alberts, Susan C.
    et al.
    Altmann, Jeanne
    Brockman, Diane K.
    Cords, Marina
    Fedigan, Linda M.
    Pusey, Anne
    Stoinski, Tara S.
    Strier, Karen B.
    Morris, William F.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Bronikowski, Anne M.
    Reproductive aging patterns in primates reveal that humans are distinct2013In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 110, no 33, p. 13440-13445Article in journal (Refereed)
    Abstract [en]

    Women rarely give birth after similar to 45 y of age, and they experience the cessation of reproductive cycles, menopause, at similar to 50 y of age after a fertility decline lasting almost two decades. Such reproductive senescence in mid-lifespan is an evolutionary puzzle of enduring interest because it should be inherently disadvantageous. Furthermore, comparative data on reproductive senescence from other primates, or indeed other mammals, remains relatively rare. Here we carried out a unique detailed comparative study of reproductive senescence in seven species of nonhuman primates in natural populations, using long-term, individual-based data, and compared them to a population of humans experiencing natural fertility and mortality. In four of seven primate species we found that reproductive senescence occurred before death only in a small minority of individuals. In three primate species we found evidence of reproductive senescence that accelerated throughout adulthood; however, its initial rate was much lower than mortality, so that relatively few individuals experienced reproductive senescence before death. In contrast, the human population showed the predicted and well-known pattern in which reproductive senescence occurred before death for many women and its rate accelerated throughout adulthood. These results provide strong support for the hypothesis that reproductive senescence in midlife, although apparent in natural-fertility, natural-mortality populations of humans, is generally absent in other primates living in such populations.

  • 234.
    Alcalde, Joaquín
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    The effects of endocrine disruptor cocktails on bleak (Alburnus alburnus) behavior, growth, and morphology2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 235.
    Alcantara, JM
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Evolutionary Biology.
    Rey, PJ
    Valera, F
    Sanchez-Lafuente, AM
    Factors shaping the seedfall pattern of a bird-dispersed plant2000In: ECOLOGY, ISSN 0012-9658, Vol. 81, no 7, p. 1937-1950Article in journal (Refereed)
    Abstract [en]

    The spatial distribution of seeds can influence several parameters of the natural regeneration of plant populations. Factors shaping seedfall patterns have been typically explored from the tree perspective (seed shadow) or from the population perspective

  • 236.
    Alessi, Nicola
    et al.
    Free Univ Bozen Bolzano, Fac Sci & Technol, Bozen Bolzano, Italy.
    Tesitel, Jakub
    Masaryk Univ, Dept Bot, Brno, Czech Republic.
    Zerbe, Stefan
    Free Univ Bozen Bolzano, Fac Sci & Technol, Bozen Bolzano, Italy.
    Spada, Francesco
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Sapienza Univ Roma, Dept Environm Biol, Rome, Italy.
    Agrillo, Emiliano
    Sapienza Univ Roma, Dept Environm Biol, Rome, Italy.
    Wellstein, Camilla
    Free Univ Bozen Bolzano, Fac Sci & Technol, Bozen Bolzano, Italy.
    Ancient refugia and present-day habitat suitability of native laurophylls in Italy2019In: Journal of Vegetation Science, ISSN 1100-9233, E-ISSN 1654-1103, Vol. 30, no 3, p. 564-574Article in journal (Refereed)
    Abstract [en]

    Questions European native laurophyllous species are interesting for their biogeography and evolutionary history, as well as for their responses to global changes. We identified Italian native laurophylls on the basis of morphology, biogeographical history and ecological niche to study whether these species are in equilibrium with the present-day climate. Furthermore, we localized Quaternary refugia and areas of potential spread of native laurophylls using distribution patterns of realized and potential aggregations of native laurophylls, respectively. Location Italy. Methods We extracted data for 17 087 forest plots from a phytosociological database. Detrended Correspondence Analysis of these plots with overlay of climatic and environmental variables was performed to identify native laurophylls, i.e., evergreen broad-leaved species of late Tertiary radiation, occupying a warm and humid niche. Potential ranges of laurophylls were calculated using Beals' index of sociological favourability. The realized/potential range-size ratio was calculated for each single laurophyll to understand whether it is in equilibrium with the present-day climate. Distribution patterns of realized and potential aggregations of laurophylls were mapped. Results Ordination analysis provided a selection of 11 species as Italian native laurophylls. Most of them occupied less than half of their estimated potential range. Realized aggregations richest in native laurophylls were localized in the central Apennines. However, the Italian forests showed high potential for native laurophylls with the richest potential aggregations in the whole Apennines and in the southern Alps. Conclusions Most of the Italian native laurophylls showed non-equilibrium with the current climate, suggesting that late-Quaternary events could better explain their present-day distribution than on-going climate change. Furthermore, their refugia in central Italy suggest the persistence in sites with temperate climate during Quaternary environmental changes. The high suitability of Italian forests for laurophylls, along with global changes, suggests possible future spreading of these species.

  • 237.
    Alessi, Nicola
    et al.
    Free Univ Bozen Bolzano, Fac Sci & Technol, Pzza Univ 5, I-39100 Bozen Bolzano, Italy.
    Wellstein, Camilla
    Free Univ Bozen Bolzano, Fac Sci & Technol, Pzza Univ 5, I-39100 Bozen Bolzano, Italy.
    Spada, Francesco
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Sapienza Univ Roma, Dept Environm Biol, Lgo Cristina di Svezia 24, I-00165 Rome.
    Zerbe, Stefan
    Free Univ Bozen Bolzano, Fac Sci & Technol, Pzza Univ 5, I-39100 Bozen Bolzano, Italy.
    Phytocoenological approach to the ecology of Laurus nobilis L. in Italy2018In: Rendiconti Lincei SCIENZE FISICHE E NATURALI, ISSN 2037-4631, E-ISSN 1720-0776, Vol. 29, no 2, p. 343-354Article in journal (Refereed)
    Abstract [en]

    Laurus nobilis L. (Laurel) is considered one of the most emblematic epigones of the late-Tertiary laurophyllous biome, persisting within the Mediterranean vegetation. Describing its present ecology and coenology is crucial to understand its biogeographical history as well as to develop consistent conservation and management practices in the context of the European Habitat Directive. We used recently available vegetation and environmental databases to investigate the coenological amplitude of Laurus in Italy, and to elucidate significant aspects of its persistence in the country. The coenological amplitude was assessed using the clustering method. Ordination techniques and regression trees were used to understand which environmental factors influence, respectively, the occurrence and the abundance of the species and, therefore, characterize its niche. Our results show a wide coenological amplitude of Laurus with respect to other laurophyllous species, growing within a wide range of forest communities. While the occurrence of the species is limited by winter temperature and favored by precipitation seasonality, changes in its abundance show a more refined pattern. In this latter case, two main groups of Laurus populations were differentiated based on water availability. The first group depends on abundant precipitations during the year while the second one buffers the summer aridity with soils rich in nutrients and moisture. Our findings provide crucial knowledge on Laurus habitats in Italy. However, discrepancies between our results and guidelines of the European Habitat Directive arose. The results presented here allow scientifically sound procedures for the regional conservation and management program.

  • 238.
    Alexandersson, R
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Evolutionary Biology.
    Johnson, SD
    Pollinator-mediated selection on flower-tube length in a hawkmoth-pollinated Gladiolus2002In: Proceedings of the Royal Society of London B, Vol. 269, p. 631-636Article in journal (Refereed)
  • 239.
    Alexiou, Athanasios
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Sets of Genes Predict Survival of Glioblastoma Patients2016Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 240.
    Alexis, Laura
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Alftrén, Ida
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Elvmarker, Josefin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Mach, Klara-Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Nyman, Rebecca
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    DETEKTERA MERA!: - En studie av LigandTracer® och andra vanliga detektionstekniker för interaktion inom antikroppsutveckling2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Ridgeview Instruments AB är ett företag, med säte i Uppsala, som bland annat utvecklar mjukvara för detektionsanalys och detektionsinstrumenten LigandTracer®. Instrumenten detekterar cellinteraktioner i realtid och tillhandahåller information om hur interaktion mellan undersökt ligand och receptor sker. LigandTracer® används bland annat vid cancerstudier och affinitetsstudier av antikroppsinbindning till antigener på celler.

     

    LigandTracer® och teknologin bakom den har studerats för att hitta de främsta styrkorna samt utvecklingsområden i jämförelse med andra detektionstekniker. Dessa tekniker är surface plasmon resonance, BioLayer Interferometry, quartz crystal microbalance samt surface acoustic wave. Främsta styrkan hos detektion med LigandTracer® är att stor mängd data som beskriver interaktionerna erhålls. Information av denna typ är viktig för att få en helhetsbild av cellers ytprotein. Därför kan instrumenten exempelvis användas som kvalitetssäkrande steg i antikroppsprocessen. LigandTracer® kan även användas för studier av hela celler och vävnader. Utöver detta finns styrkor som minimerar det laborativa arbetet, så som tvättar i prepareringssteg. Detta gör att både tid och reagens sparas.

     

    En utvecklingsmöjlighet för LigandTracer® är egenskapen att kunna detektera fler antikroppar och cellinjer samtidigt. Då mjukvaran TraceDrawer™ är ett viktigt tillbehör för utvärderingen av detektionen, skulle utveckling med avseende på celldynamiken och receptorernas rörelsemönster kunna förbättra instrumenten ytterligare.

  • 241.
    Alfjorden, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Experimental Spironucleus infections in Atlantic salmon (Salmo salar): Hidden secrets of the life cycle of Spironucleus salmonicida revealed2018Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    We have performed experimental infections of Atlantic salmon (Salmo salar) from the Baltic Sea region with the protozoan parasite Spironucleus salmonicida. By this infection trial we have been able to show that the life cycle may use an alternative route of transmission. Instead of the commonly used faecal-oral route, the parasites can also be excreted directly into the surrounding water from the mucous layer of the skin or from an ulcerated skin lesion. Three different stages of the infection were identified: one intestinal, one blood stage and one tissue stage. New putative life-cycle forms of S. salmonicida cells detected by ex-vivo cell-cultures. Similar cells were also observed in imprints from skin lesions sampled during the experimental infection trials. The cells differed morphologically, from normal trophozoite cells and indicate an alternative cell-cycle when exposed to salmonid host cells.

    The full text will be freely available from 2023-12-31 19:13
  • 242. Algesten, Grete
    et al.
    Brydsten, Lars
    Jonsson, Per
    Kortelainen, Pirkko
    Löfgren, Stefan
    Rahm, Lars
    Räike, Antti
    Sobek, Sebastian
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution.
    Tranvik, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution.
    Wikner, Johan
    Jansson, Mats
    Organic carbon budget for the Gulf of Bothnia2006In: Journal of Marine Systems, ISSN 0924-7963, E-ISSN 1879-1573, Vol. 63, no 3-4, p. 155-161Article in journal (Refereed)
    Abstract [en]

    We calculated input of organic carbon to the unproductive, brackish water basin of the Gulf of Bothnia from rivers, point sources and the atmosphere. We also calculated the net exchange of organic carbon between the Gulf of Bothnia and the adjacent marine system, the Baltic Proper. We compared the input with sinks for organic carbon; permanent incorporation in sediments and mineralization and subsequent evasion of CO2 to the atmosphere. The major fluxes were riverine input (1500 Gg C year(-1)), exchange with the Baltic Proper (depending on which of several possible DOC concentration differences between the basins that was used in the calculation, the flux varied between an outflow of 466 and an input of 950 Gg C year(-1)), sediment burial (1100 Gg C year) and evasion to the atmosphere (3610 Gg C year(-1)). The largest single net flux was the emission of CO2 to the atmosphere, mainly caused by bacterial mineralization of organic carbon. Input and output did not match in our budget which we ascribe uncertainties in the calculation of the exchange of organic carbon between the Gulf of Bothnia and the Baltic Proper, and the fact that CO2 emission, which in our calculation represented 1 year (2002) may have been overestimated in comparison with long-term means. We conclude that net heterotrophy of the Gulf of Bothnia was due to input of organic carbon from both the catchment and from the Baltic Proper and that the future degree of net heterotrophy will be sensible to both catchment export of organic carbon and to the ongoing eutrophication of the Baltic Proper.

  • 243. Algesten, Grete
    et al.
    Sobek, Sebastian
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    Bergström, Ann-Kristin
    Jonsson, Anders
    Tranvik, Lars J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    Jansson, Mats
    Contribution of sediment respiration to summer CO2 emission from low productive boreal and subarctic lakes2005In: Microbial Ecology, ISSN 0095-3628, E-ISSN 1432-184X, Vol. 50, no 4, p. 529-535Article in journal (Refereed)
    Abstract [en]

    We measured sediment production of carbon dioxide (CO2) and methane (CH4) and the net flux of CO2 across the surfaces of 15 boreal and subarctic lakes of different humic contents. Sediment respiration measurements were made in situ under ambient light conditions. The flux of CO2 between sediment and water varied between an uptake of 53 and an efflux of 182 mg C m−2 day−1 from the sediments. The mean respiration rate for sediments in contact with the upper mixed layer (SedR) was positively correlated to dissolved organic carbon (DOC) concentration in the water (r 2 = 0.61). The net flux of CO2 across the lake surface [net ecosystem exchange (NEE)] was also closely correlated to DOC concentration in the upper mixed layer (r 2 = 0.73). The respiration in the water column was generally 10-fold higher per unit lake area compared to sediment respiration. Lakes with DOC concentrations <5.6 mg L−1 had net consumption of CO2 in the sediments, which we ascribe to benthic primary production. Only lakes with very low DOC concentrations were net autotrophic (<2.6 mg L−1) due to the dominance of dissolved allochthonous organic carbon in the water as an energy source for aquatic organisms. In addition to previous findings of allochthonous organic matter as an important driver of heterotrophic metabolism in the water column of lakes, this study suggests that sediment metabolism is also highly dependent on allochthonous carbon sources.

  • 244. Algesten, Grete
    et al.
    Sobek, Sebastian
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    Bergström, Ann-Kristin
    Ågren, Anneli
    Tranvik, Lars J.
    Jansson, Mats
    Role of lakes for organic carbon cycling in the boreal zone2004In: Global Change Biology, Vol. 10, p. 141-147Article in journal (Refereed)
  • 245. Algesten, Grete
    et al.
    Wikner, Johan
    Sobek, Sebastian
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology. Limnologi.
    Tranvik, Lars J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology. Limnologi.
    Jansson, Mats
    Seasonal variation of CO2 saturation in the Gulf of Bothnia: indications of marine net heterotrophy2004In: Global Biogeochemical Cycles, ISSN 1944-9224 EISSN, Vol. 18, no 4, p. GB4021-Article in journal (Refereed)
    Abstract [en]

    [1] Seasonal variation of pCO2 and primary and bacterioplankton production were measured in the Gulf of Bothnia during an annual cycle. Surface water was supersaturated with CO2 on an annual basis, indicating net heterotrophy and a source of CO2 to the atmosphere. However, the Gulf of Bothnia oscillated between being a sink and a source of CO2 over the studied period, largely decided by temporal variation in bacterial respiration (BR) and primary production (PP) in the water column above the pycnocline. The calculated annual respiration-production balance (BR-PP) was very similar to the estimated CO2 emission from the Gulf of Bothnia, which indicates that these processes were major determinants of the exchange of CO2 between water and atmosphere. The southern basin (the Bothnian Sea) had a lower net release of CO2 to the atmosphere than the northern Bothnian Bay (7.1 and 9.7 mmol C m−2 d−1, respectively), due to higher primary production, which to a larger extent balanced respiration in this basin.

  • 246. Alho, J. S.
    et al.
    Herczeg, G.
    Laugen, A. T.
    Raesaenen, K.
    Laurila, Anssi
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology.
    Merila, J.
    Allen's rule revisited: quantitative genetics of extremity length in the common frog along a latitudinal gradient2011In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 24, no 1, p. 59-70Article in journal (Refereed)
    Abstract [en]

    Ecogeographical rules linking climate to morphology have gained renewed interest because of climate change. Yet few studies have evaluated to what extent geographical trends ascribed to these rules have a genetic, rather than environmentally determined, basis. This applies especially to Allen's rule, which states that the relative extremity length decreases with increasing latitude. We studied leg length in the common frog (Rana temporaria) along a 1500 km latitudinal gradient utilizing wild and common garden data. In the wild, the body size-corrected femur and tibia lengths did not conform to Allen's rule but peaked at mid-latitudes. However, the ratio of femur to tibia length increased in the north, and the common garden data revealed a genetic cline consistent with Allen's rule in some trait and treatment combinations. While selection may have shortened the leg length in the north, the genetic trend seems to be partially masked by environmental effects.

  • 247. Alho, Jussi S.
    et al.
    Herczeg, Gabor
    Söderman, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution.
    Laurila, Anssi
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution.
    Jönsson, K. Ingemar
    Merilä, Juha
    Increasing melanism along a latitudinal gradient in a widespread amphibian: local adaptation, ontogenic or environmental plasticity?2010In: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 10, no 1, p. 317-Article in journal (Refereed)
    Abstract [en]
    Background: The thermal benefits of melanism in ectothermic animals are widely recognized, but relatively little is known about population differentiation in the degree of melanism along thermal gradients, and the relative contributions of genetic vs. environmental components into the level of melanism expressed. We investigated variation in the degree of melanism in the common frog (Rana temporaria; an active heliotherm thermoregulator) by comparing the degree of melanism (i) among twelve populations spanning over 1500 km long latitudinal gradient across the Scandinavian Peninsula and (ii) between two populations from latitudinal extremes subjected to larval temperature treatments in a common garden experiment. Results: We found that the degree of melanism increased steeply in the wild as a function of latitude. Comparison of the degree of population differentiation in melanism (P-ST) and neutral marker loci (F-ST) revealed that the P-ST >F-ST, indicating that the differences cannot be explained by random genetic drift alone. However, the latitudinal trend observed in the wild was not present in the common garden data, suggesting that the cline in nature is not attributable to direct genetic differences. Conclusions: As straightforward local adaptation can be ruled out, the observed trend is likely to result from environment-driven phenotypic plasticity or ontogenetic plasticity coupled with population differences in age structure. In general, our results provide an example how phenotypic plasticity or even plain ontogeny can drive latitudinal clines and result in patterns perfectly matching the genetic differences expected under adaptive hypotheses.
  • 248. Ali, N.
    et al.
    Junaid, M.
    Ahmad, D.
    urRahman, M.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Katzenmeier, G.
    Antibacterial and antifungal activity of solvent extracts from Plumeria obtusa Linn2014In: Tropical Biomedicine, ISSN 0127-5720, Vol. 31, no 4, p. 607-615Article in journal (Refereed)
    Abstract [en]

    Extracts of Plumeria obtusa are widely used in ethnomedicine and have been investigated for a variety of biological activities; however, the antimicrobial activity of P. obtusa flowers is poorly characterized. In this study, the antimicrobial activities of different solvents (petroleum ether, ethyl acetate, chloroform, isobutanol and ethanol) extracts from flowers of P. obtusa were investigated by a disc diffusion method against Gram-positive bacteria, Gram-negative bacteria and a fungus. All extracts exhibited growth inhibition of all microorganisms at variable degrees as measured by relative zones of inhibition, however, the petroleum ether extract was ineffective against Klebsiella pneumonia and ethyl acetate and isobutanol extracts were ineffective against Pseudomonas aeruginosa. The most susceptible Gram-positive bacterium was Bacillus subtilis while the most resistant Gram-positive bacterium was Staphylococcus aureus. Erwinia carotovora was the most susceptible Gram-negative bacterium while P. aeruginosa was highly resistant among the Gram-negative bacteria. In this study, for the first time, we investigated the antimicrobial activity of several different solvent extracts from flowers of P. obtusa against a broad spectrum of human-pathogenic microorganisms. These compounds warrant further investigation by isolation and structural elucidation with the aim to find novel and affordable bioactive compounds for the treatment of infectious diseases.

  • 249.
    Ali, Raja Hashim
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Bogusz, Marcin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Whelan, Simon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    A graph-based approach for improving the homologyinference in multiple sequence alignmentsManuscript (preprint) (Other academic)
    Abstract [en]

    Multiple sequence alignment (MSA) is ubiquitous in evolutionary studies and other areas ofbioinformatics. In nearly all cases MSAs are taken to be a known and xed quantity on which toperform downstream analysis despite extensive evidence that MSA accuracy and uncertainty aectsresults. Mistakes in the MSA are known to cause a wide range of problems for downstream evolutionaryinference, ranging from false inference of positive selection to long branch attraction artifacts. The mostpopular approach to dealing with this problem is to remove (lter) specic columns in the MSA thatare thought to be prone to error, either through proximity to gaps or through some scoring function.Although popular, this approach has had mixed success and several studies have even suggested thatltering might be detrimental to phylogenetic studies. Here we present a dierent approach to dealingwith MSA accuracy and uncertainty through a graph-based approach implemented in the freely availablesoftware Divvier. The aim of Divvier is to identify clusters of characters that have strong statisticalevidence of shared homology, based on the output of a pair hidden Markov model. These clusters canthen be used to either lter characters out the MSA, through a process we call partial ltering, or torepresent each of the clusters in a new column, through a process we call divvying up. We validateour approach through its performance on real and simulated benchmarks, nding Divvier substantiallyoutperforms all other ltering software for treating MSAs by retaining more true positive homology callsand removing more false positive homology calls. We also nd that Divvier, in contrast to other lteringtools, can alleviate long branch attraction artifacts induced by MSA and reduces the variation in treeestimates caused by MSA uncertainty.

  • 250. Alizadehheidari, M.
    et al.
    Frykholm, K.
    Fritzsche, J.
    Wigenius, J.
    Modesti, M.
    Persson, Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Computational and Systems Biology.
    Westerlund, F.
    Probing the Physical Properties of a DNA-Protein Complex Using Nanofluidic Channels2013In: European Biophysics Journal, ISSN 0175-7571, E-ISSN 1432-1017, Vol. 42, p. S134-S134Article in journal (Other academic)
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