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  • 251.
    Backström, Niclas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Saetre, Glenn-Peter
    Ellegren, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Inferring the demographic history of European Ficedula flycatcher populations2013In: BMC Evolutionary Biology, E-ISSN 1471-2148, Vol. 13, p. 2-Article in journal (Refereed)
    Abstract [en]

    Background: Inference of population and species histories and population stratification using genetic data is important for discriminating between different speciation scenarios and for correct interpretation of genome scans for signs of adaptive evolution and trait association. Here we use data from 24 intronic loci re-sequenced in population samples of two closely related species, the pied flycatcher and the collared flycatcher. Results: We applied Isolation-Migration models, assignment analyses and estimated the genetic differentiation and diversity between species and between populations within species. The data indicate a divergence time between the species of <1 million years, significantly shorter than previous estimates using mtDNA, point to a scenario with unidirectional gene-flow from the pied flycatcher into the collared flycatcher and imply that barriers to hybridisation are still permeable in a recently established hybrid zone. Furthermore, we detect significant population stratification, predominantly between the Spanish population and other pied flycatcher populations. Conclusions: Our results provide further evidence for a divergence process where different genomic regions may be at different stages of speciation. We also conclude that forthcoming analyses of genotype-phenotype relations in these ecological model species should be designed to take population stratification into account.

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  • 252.
    Backström, Niclas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Shipilina, Daria
    Bloom, Mozes
    Edwards, Scott
    Cis-regulatory sequence variation and association with Mycoplasma load in natural populations of the house finch (Carpodacus mexicanus)2013In: Ecology and Evolution, E-ISSN 2045-7758, Vol. 3, no 3, p. 655-666Article in journal (Refereed)
    Abstract [en]

    Characterization of the genetic basis of fitness traits in natural populations is important for understanding how organisms adapt to the changing environment and to novel events, such as epizootics. However, candidate fitness-influencing loci, such as regulatory regions, are usually unavailable in nonmodel species. Here, we analyze sequence data from targeted resequencing of the cis-regulatory regions of three candidate genes for disease resistance (CD74, HSP90α, and LCP1) in populations of the house finch (Carpodacus mexicanus) historically exposed (Alabama) and naïve (Arizona) to Mycoplasma gallisepticum. Our study, the first to quantify variation in regulatory regions in wild birds, reveals that the upstream regions of CD74 and HSP90α are GC-rich, with the former exhibiting unusually low sequence variation for this species. We identified two SNPs, located in a GC-rich region immediately upstream of an inferred promoter site in the gene HSP90α, that were significantly associated with Mycoplasma pathogen load in the two populations. The SNPs are closely linked and situated in potential regulatory sequences: one in a binding site for the transcription factor nuclear NFYα and the other in a dinucleotide microsatellite ((GC)6). The genotype associated with pathogen load in the putative NFYα binding site was significantly overrepresented in the Alabama birds. However, we did not see strong effects of selection at this SNP, perhaps because selection has acted on standing genetic variation over an extremely short time in a highly recombining region. Our study is a useful starting point to explore functional relationships between sequence polymorphisms, gene expression, and phenotypic traits, such as pathogen resistance that affect fitness in the wild.

  • 253.
    Backström, Niclas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Väli, Ulo
    Sex- and species-biased gene flow in a spotted eagle hybrid zone.2011In: BMC Evolutionary Biology, E-ISSN 1471-2148, Vol. 11Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Recent theoretical and empirical work points toward a significant role for sex-chromosome linked genes in the evolution of traits that induce reproductive isolation and for traits that evolve under influence of sexual selection. Empirical studies including recently diverged (Pleistocene), short-lived avian species pairs with short generation times have found that introgression occurs on the autosomes but not on the Z-chromosome. Here we study genetic differentiation and gene flow in the long-lived greater spotted eagle (Aquila clanga) and lesser spotted eagle (A. pomarina), two species with comparatively long generation times.

    RESULTS: Our data suggest that there is a directional bias in migration rates between hybridizing spotted eagles in eastern Europe. We find that a model including post divergence gene flow fits our data best for both autosomal and Z-chromosome linked loci but, for the Z-chromosome, the rate is reduced in the direction from A. pomarina to A. clanga.

    CONCLUSIONS: The fact that some introgression still occurs on the Z-chromosome between these species suggests that the differentiation process is in a more premature phase in our study system than in previously studied avian species pairs and that could be explained by a shorter divergence time and/or a longer average generation time in the spotted eagles. The results are in agreement with field observations and provide further insight into the role of sex-linked loci for the build-up of barriers to gene flow among diverging populations and species.

  • 254.
    Backström, Niclas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Zhang, Qu
    Edwards, Scott V.
    Evidence from a House Finch (Haemorhous mexicanus) Spleen Transcriptome for Adaptive Evolution and Biased Gene Conversion in Passerine Birds2013In: Molecular biology and evolution, ISSN 0737-4038, E-ISSN 1537-1719, Vol. 30, no 5, p. 1046-1050Article in journal (Refereed)
    Abstract [en]

    Identifying genes influenced by natural selection can provide information about lineage-specific adaptations, and transcriptomes generated by next-generation sequencing are a useful resource for identifying such genes. Here, we utilize a spleen transcriptome for the house finch (Haemorhous mexicanus), an emerging model for sexual selection and disease ecology, together with previously sequenced avian genomes (chicken, turkey, and zebra finch), to investigate lineage-specific adaptations within birds. An analysis of 4,398 orthologous genes revealed a significantly higher ratio of nonsynonymous to synonymous substitutions and significantly higher GC content in passerines than in galliforms, an observation deviating from strictly neutral expectations but consistent with an effect of biased gene conversion on the evolutionary rate in passerines. These data also showed that genes exhibiting signs of positive selection and fast evolution in passerines have functional roles related to fat metabolism, neurodevelopment, and ion binding.

  • 255.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Det är långt mer än doften som gör skvattram unik2022In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 116, no 1, p. 22-31Article in journal (Refereed)
  • 256.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Dynamik och evolution på de östafrikanska bergen2017In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 111, no 5, p. 228-239Article in journal (Refereed)
    Abstract [en]

    A brief overview of the conspicuous alpine flora and vegetation of the East African mountains is presented. 

  • 257.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ett etnobotaniskt livsverk2015In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 109, no 6, p. 346-347Article in journal (Refereed)
    Abstract [sv]

    Vagn J. Brøndegaard skrev mer än 1600 artiklar om allt som hade med relationen mellan växter och människor att göra. Många av dessa har nu ställts samman i två vackra volymer.

  • 258.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Gunnar Björkman och hans expedition till Lule lappmark 1924: Gunnar Björkman’s expedition to Swedish Lapland in 19242013In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 107, no 6, p. 354-358Article in journal (Other academic)
    Abstract [en]

    Drawings by Torsten Höjer from Gunnar Björkman's botanical expedition to Swedish Lapland in 1924 are presented with some biographical notes on Björkman. The paleontologist  Birger Bohlin also participated.

  • 259.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Mossflora över Sankta Helena2013In: Myrinia, ISSN 1102-4194, Vol. 23, p. 84-87Article in journal (Other academic)
    Abstract [en]

    A new bryophyte flora of St. Helena in the South Atlantic is presented. Of the known 110 species, 26 are (as presently known) endemic.

  • 260.
    Backéus, Ingvar
    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, Swedish Biodiversity Centre.
    Om São Tomé, begonior och öar i havet2018In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 112, no 1, p. 32-40Article in journal (Refereed)
    Abstract [en]

    A brief overview of the vegetation of São Tomë and Príncipe is presented. The several endemic and large species of Begonia on the islands are discussed in more detail.

  • 261.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Swedish Biodiversity Centre. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Sankta Helena: en hotad endemisk flora. 1. Den ursprungliga floran och vegetationen och den historiska utvecklingen2014In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 108, no 3-4, p. 206-218Article in journal (Other academic)
    Abstract [en]

    An overview of the endemic flora and the original vegetation of Saint Helena is given.

  • 262.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Swedish Biodiversity Centre. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Sankta Helena: en hotad endemisk flora. 2. situationen i dag2014In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 108, no 5, p. 232-244Article in journal (Refereed)
    Abstract [en]

    The present-day situation for the endemic flora of Saint Helena is described.

  • 263.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Växterna på Indiska oceanens öar kom över havet.2020In: Fauna & flora: en spegling av svensk natur, E-ISSN 0014-8903, Vol. 115, no 3, p. 34-48Article in journal (Refereed)
  • 264.
    Backéus, Ingvar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Swedish Biodiversity Centre. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Emanuelsson, Urban
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Swedish Biodiversity Centre.
    Karakin, Vladimir (Contributor)
    Russian Academy of Sciences, Far East Division, Vladivostok.
    von Bothmer, Roland (Contributor)
    Swedish University of Agriculture, Alnarp.
    The rural landscapes of Northeast Asia.2016Book (Other academic)
  • 265.
    Backéus, Ingvar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Gunnarsson, Urban
    Swedish Species Information Centre, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Strömquist, Lennart
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Human Geography.
    Bog vegetation re-mapped after 63 and 103 years: expansion of Rhynchospora alba (Studies on Skagershultsmossen 2)2023In: Mires and Peat, E-ISSN 1819-754X, Vol. 29, p. 1-16, article id 18Article in journal (Refereed)
    Abstract [en]

    The vegetation in an area of the ombrotrophic bog Skagershultsmossen, South-Central Sweden, was mapped in 2010. The same area was previously surveyed in 1907 and 1970. Only small changes were found in 1970, in contrast to the situation in 2010, when a large shift in the vegetation was observed. The previously dominating vegetation type, lawns dominated by Eriophorum vaginatum, had more or less disappeared and was replaced by carpet vegetation dominated by Rhynchospora alba, Sphagnum tenellum and S. balticum. Also, the carpets dominated by Scheuchzeria palustris had decreased to a large extent. There are several possible climatic explanations behind the changes, and we suggest that increased frost action linked to the reduction in snow cover may be important. The shift in the vegetation has most certainly led to a decrease in peat productivity and, hence, a reduction in carbon sequestration by the bog is assumed. Skagershultsmossen is an important reference site for future studies of long-term vegetation changes.

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  • 266.
    Backéus, Ingvar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    "Det har vi vetat hela tiden!": akademikerna och lövängen för hundra år sedan2019In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 113, no 3/4, p. 219-231Article in journal (Refereed)
    Abstract [en]

    Mown meadows with scattered trees were a characteristic of the old Swedish landscape.  It has been an established truth that the botanists, particularly R. Sernander and H. Hesselman, did not understand that the meadows would turn into forests when abandoned, whereas the human geographer M. Sjöbeck in several publications from 1927 onwards made this clear. This view was supported by, i.a,. L.-G. Romell.

     We have scrutinized the literature and the minutes of the Plant Biology Seminar in Uppsala from 1892 to 1944, in order to understand Sernander’s views. Hesselman considered the matter uncertain. Sernander probably understood the dynamics also before 1927, but his standpoint was influenced by a wish to restore the postglacial broadleaved forests of which he saw the meadows as degraded relicts. This could be done by leaving meadows for free development. Gradually he saw the need also to maintain meadows and the cultural landscape as such. Several other botanists, e.g. G. Samuelsson and G. Einar Du Rietz, already early on understood the dependence of meadows on human management. 

  • 267.
    Backéus, Ingvar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Var Sellingaffären kulmen på en sekellång botanisk konflikt?2018In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 112, no 6, p. 380-393Article in journal (Refereed)
    Abstract [en]

    The 1950s saw a series of miscarriages of justice against public persons in Sweden. In one of these, the Royal Swedish Academy of Sciences tried to force Olof Selling from his professorship in paleobotany at the Swedish Museum of Natural History, on the basis of mental illness, but this failed after a long and public calamity. In his book Naturen inför rätta [Nature facing trial], Keith Wijkander (2017) claims that Selling was the victimof a century-long conflict between botanists in Uppsala and Stockholm,and places Selling in the Uppsala camp. We try to give a more balanced picture of the relationships between plant ecology in Uppsala and Stockholm during the early 20th century. R. Sernander, L.-G. Romell and G. E. Du Rietz are among the main actors. The fierce debates between the two camps make this an interesting period in Swedish botany.

  • 268.
    Backéus, Ingvar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Skoglund, Jerry
    Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Skarpe, Christina
    Campus Evenstad, Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, Inland Norway University of Applied Sciences, Elverum, Norway.
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Diameter growth of trees in miombo and acacia woodland in an eroded landscape in NE Tanzania2022In: African Journal of Ecology, ISSN 0141-6707, E-ISSN 1365-2028, Vol. 60, no 3, p. 714-722Article in journal (Refereed)
    Abstract [en]

    Diameter increment of trees typical of miombo and acacia woodland was studied dur- ing a period of 20 years in Kondoa district, Tanzania. The study was performed in permanent plots in a severely degraded area subjected to considerable restoration efforts. A total of 15 species were selected from a database collected within a pro- ject for monitoring the landscape recovery. Growth performance of African woodland species was searched for in the literature for comparison, and a comprehensive list of citations was compiled. We found growth to fall within the range reported in earlier studies, although growth varied both between and within species. There are reports that the radial increments of trees are unimodal over their lifespan, but we found no clear support. In several species, the annual growth increased with stem diameter. Growth during the rainy ENSO year 1997/98 was pairwise compared with the preced- ing two years and was found to be significantly higher during the wet year, pointing to soil water as a limiting factor. We conclude that free development is an alternative to tree planting on marginal land.

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  • 269. Badou, Sylvestre A.
    et al.
    Furneaux, Brendan R.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    De Kesel, André
    Kalsoom, Faheema
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Houdanon, Roel D.
    Ryberg, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Yorou, Nourou S.
    Paxilloboletus gen. nov., a new lamellate bolete genus from tropical Africa2022In: Mycological progress, ISSN 1617-416X, E-ISSN 1861-8952, Vol. 21, no 1, p. 243-256Article in journal (Refereed)
    Abstract [en]

    This study presents Paxilloboletus gen. nov., a new lamellate bolete genus represented by two tropical African species, Paxilloboletus africanus sp. nov. and Paxilloboletus latisporus sp. nov. Although the new taxa strongly resemble Paxillus (Paxillaceae), they lack clamp connections and form a separate generic clade within the Boletaceae phylogeny. The new species are lookalikes, morphologically only separable by their spore morphology. Descriptions and illustrations of the new genus and new species are given, as well as comments on ecology, distribution, and morphological differences with other gilled Boletaceae.

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  • 270. Bagatini, Inessa Lacativa
    et al.
    Eiler, Alexander
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Bertilsson, Stefan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Klaveness, Dag
    Tessarolli, Leticia Piton
    Henriques Vieira, Armando Augusto
    Host-Specificity and Dynamics in Bacterial Communities Associated with Bloom-Forming Freshwater Phytoplankton2014In: PLOS ONE, E-ISSN 1932-6203, Vol. 9, no 1, p. e85950-Article in journal (Refereed)
    Abstract [en]

    Many freshwater phytoplankton species have the potential to form transient nuisance blooms that affect water quality and other aquatic biota. Heterotrophic bacteria can influence such blooms via nutrient regeneration but also via antagonism and other biotic interactions. We studied the composition of bacterial communities associated with three bloom-forming freshwater phytoplankton species, the diatom Aulacoseira granulata and the cyanobacteria Microcystis aeruginosa and Cylindrospermopsis raciborskii. Experimental cultures incubated with and without lake bacteria were sampled in three different growth phases and bacterial community composition was assessed by 454-Pyrosequencing of 16S rRNA gene amplicons. Betaproteobacteria were dominant in all cultures inoculated with lake bacteria, but decreased during the experiment. In contrast, Alphaproteobacteria, which made up the second most abundant class of bacteria, increased overall during the course of the experiment. Other bacterial classes responded in contrasting ways to the experimental incubations causing significantly different bacterial communities to develop in response to host phytoplankton species, growth phase and between attached and free-living fractions. Differences in bacterial community composition between cyanobacteria and diatom cultures were greater than between the two cyanobacteria. Despite the significance, major differences between phytoplankton cultures were in the proportion of the OTUs rather than in the absence or presence of specific taxa. Different phytoplankton species favoring different bacterial communities may have important consequences for the fate of organic matter in systems where these bloom forming species occur. The dynamics and development of transient blooms may also be affected as bacterial communities seem to influence phytoplankton species growth in contrasting ways.

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  • 271. Bagchi, Basabi
    et al.
    Corbel, Quentin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. University of Valencia.
    Khan, Imroze
    Payne, Ellen
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Banerji, Devshuvam
    Liljestrand-Rönn, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Martinossi-Allibert, Ivain
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Baur, Julian
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sayadi, Ahmed
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - BMC, Biochemistry.
    Immonen, Elina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Arnqvist, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Söderhäll, Irene
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Comparative Physiology.
    Berger, David
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sexual conflict drives micro- and macroevolution of sexual dimorphism in immunity2021In: BMC Biology, E-ISSN 1741-7007, Vol. 19, no 1, article id 114Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: Sexual dimorphism in immunity is believed to reflect sex differences in reproductive strategies and trade-offs between competing life history demands. Sexual selection can have major effects on mating rates and sex-specific costs of mating and may thereby influence sex differences in immunity as well as associated host-pathogen dynamics. Yet, experimental evidence linking the mating system to evolved sexual dimorphism in immunity are scarce and the direct effects of mating rate on immunity are not well established. Here, we use transcriptomic analyses, experimental evolution and phylogenetic comparative methods to study the association between the mating system and sexual dimorphism in immunity in seed beetles, where mating causes internal injuries in females.

    RESULTS: We demonstrate that female phenoloxidase (PO) activity, involved in wound healing and defence against parasitic infections, is elevated relative to males. This difference is accompanied by concomitant sex differences in the expression of genes in the prophenoloxidase activating cascade. We document substantial phenotypic plasticity in female PO activity in response to mating and show that experimental evolution under enforced monogamy (resulting in low remating rates and reduced sexual conflict relative to natural polygamy) rapidly decreases female (but not male) PO activity. Moreover, monogamous females had evolved increased tolerance to bacterial infection unrelated to mating, implying that female responses to costly mating may trade off with other aspects of immune defence, an hypothesis which broadly accords with the documented sex differences in gene expression. Finally, female (but not male) PO activity shows correlated evolution with the perceived harmfulness of male genitalia across 12 species of seed beetles, suggesting that sexual conflict has a significant influence on sexual dimorphisms in immunity in this group of insects.

    CONCLUSIONS: Our study provides insights into the links between sexual conflict and sexual dimorphism in immunity and suggests that selection pressures moulded by mating interactions can lead to a sex-specific mosaic of immune responses with important implications for host-pathogen dynamics in sexually reproducing organisms.

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  • 272.
    Baho, Didier
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Resistance and resilience of microbial communities - temporal and spatial insurance against perturbations2010Independent thesis Advanced level (degree of Master (One Year)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    Bacterial communities are fundamental components of many processes occurring in aquatic ecosystems, since through microbial activities substantial amount of matter and energy is transferred from a pool of DOC to higher trophic levels. Previous studies highlighted the beneficial effects of diversity on ecosystem functioning, however studies on the resistance and resilience in microbial communities are scarce. Similarly, studies focusing on factors that might improve resistance or resilience of communities such as the influence of refuges are equally missing, although an understanding of the underlying mechanisms could be very useful in the field of conservation management. In this study, chemostat cultures were used to investigate the influence of a spatial and a temporal refuge on bacterioplankton communities’ resistance and resilience measured in terms of functioning and community composition after applying a salinity pulse disturbance. Respiration rate and substrate utilization were used to estimate bacterial functioning while community composition was determined by using T-RFLP. The perturbation was found to affect bacterial functioning and community composition. Moreover our findings indicate that the resistance and resilience measured in terms of bacterial functioning and community composition were significantly influenced by the provision of refuges.  

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  • 273.
    Baho, Didier
    et al.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Peter, Hannes
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Tranvik, Lars J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Resistance and resilience of microbial communities: temporal and spatial insurance against perturbations2012In: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 14, no 9, p. 2283-2292Article in journal (Refereed)
    Abstract [en]

    Bacteria play fundamental roles for many ecosystem processes; however, little empirical evidence is available on how environmental perturbations affect their composition and function. We investigated how spatial and temporal refuges affect the resistance and resilience of a freshwater bacterioplankton community upon a salinity pulse perturbation in continuous cultures. Attachment to a surface avoided the flushing out of cells and enabled re-colonization of the liquid phase after the perturbation, hence serving as a temporal refuge. A spatial refuge was established by introduction of bacteria from an undisturbed reservoir upstream of the continuous culture vessel, acting analogous to a regional species pool in a metacommunity. The salinity pulse affected bacterial community composition and the rates of respiration and the pattern of potential substrate utilization as well as the correlation between composition and function. Compared with the no-refuge treatment, the temporal refuge shortened return to pre-perturbation conditions, indicating enhanced community resilience. Composition and function were less disturbed in the treatment providing a spatial refuge, suggesting higher resistance. Our results highlight that spatial and temporal dynamics in general and refuges in particular need to be considered for conceptual progress in how microbial metacommunities are shaped by perturbations.

  • 274.
    Bai, Yang
    et al.
    Shanghai Acad Environm Sci, Inst Appl Ecol, Shanghai 200233, Peoples R China..
    Jiang, Bo
    Changjiang Water Resources Protect Inst, Wuhan 430051, Peoples R China..
    Wang, Min
    Shanghai Acad Environm Sci, Inst Appl Ecol, Shanghai 200233, Peoples R China..
    Li, Hui
    Yunnan Univ, Sch Urban Construct & Management, Kunming 650091, Peoples R China..
    Alatalo, Juha M.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Qatar Univ, Coll Arts & Sci, Dept Biol & Environm Sci, POB 2713, Doha, Qatar..
    Huang, Shenfa
    Shanghai Acad Environm Sci, Inst Appl Ecol, Shanghai 200233, Peoples R China..
    New ecological redline policy (ERP) to secure ecosystem services in China2016In: Land use policy, ISSN 0264-8377, E-ISSN 1873-5754, Vol. 55, p. 348-351Article in journal (Refereed)
    Abstract [en]

    China is facing huge environmental problems, with its current rapid rate of urbanization and industrialization causing biodiversity loss, ecosystem degradation, and land resources degradation on a major scale. To overcome management conflicts and secure ecosystem services, China has proposed a new 'ecological redline policy' (ERP) using ecosystem services as a way to meet its targets. By giving environmental policy redline status, China is demonstrating strong commitment in its efforts to tackle environmental degradation and secure ecosystem services for the future. This is already having impact, as the Chinese Ministry of Environmental Protection and the National Development and Reform Commission are prepared to work together to implement the new environmental policy.

  • 275.
    Bailey, Richard I.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal Ecology.
    Innocenti, Paolo
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal Ecology.
    Morrow, Edward H.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal Ecology.
    Friberg, Urban
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal Ecology.
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal Ecology.
    Female Drosophila melanogaster Gene Expression and Mate Choice: The X Chromosome Harbours Candidate Genes Underlying Sexual Isolation2011In: PLOS ONE, E-ISSN 1932-6203, Vol. 6, no 2, p. e17358-Article in journal (Refereed)
    Abstract [en]

    Background: The evolution of female choice mechanisms favouring males of their own kind is considered a crucial step during the early stages of speciation. However, although the genomics of mate choice may influence both the likelihood and speed of speciation, the identity and location of genes underlying assortative mating remain largely unknown. Methods and Findings: We used mate choice experiments and gene expression analysis of female Drosophila melanogaster to examine three key components influencing speciation. We show that the 1,498 genes in Zimbabwean female D. melanogaster whose expression levels differ when mating with more (Zimbabwean) versus less (Cosmopolitan strain) preferred males include many with high expression in the central nervous system and ovaries, are disproportionately X-linked and form a number of clusters with low recombination distance. Significant involvement of the brain and ovaries is consistent with the action of a combination of pre- and postcopulatory female choice mechanisms, while sex linkage and clustering of genes lead to high potential evolutionary rate and sheltering against the homogenizing effects of gene exchange between populations. Conclusion: Taken together our results imply favourable genomic conditions for the evolution of reproductive isolation through mate choice in Zimbabwean D. melanogaster and suggest that mate choice may, in general, act as an even more important engine of speciation than previously realized.

  • 276. Bains, Ripudaman K.
    et al.
    Kovacevic, Mirna
    Plaster, Christopher A.
    Tarekegn, Ayele
    Bekele, Endashaw
    Bradman, Neil N.
    Thomas, Mark G.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Molecular diversity and population structure at the Cytochrome P450 3A5 gene in Africa2013In: BMC Genetics, E-ISSN 1471-2156, Vol. 14, p. 34-Article in journal (Refereed)
    Abstract [en]

    Background: Cytochrome P450 3A5 (CYP3A5) is an enzyme involved in the metabolism of many therapeutic drugs. CYP3A5 expression levels vary between individuals and populations, and this contributes to adverse clinical outcomes. Variable expression is largely attributed to four alleles, CYP3A5*1 (expresser allele); CYP3A5*3 (rs776746), CYP3A5*6 (rs10264272) and CYP3A5*7 (rs41303343) (low/non-expresser alleles). Little is known about CYP3A5 variability in Africa, a region with considerable genetic diversity. Here we used a multi-disciplinary approach to characterize CYP3A5 variation in geographically and ethnically diverse populations from in and around Africa, and infer the evolutionary processes that have shaped patterns of diversity in this gene. We genotyped 2538 individuals from 36 diverse populations in and around Africa for common low/non-expresser CYP3A5 alleles, and re-sequenced the CYP3A5 gene in five Ethiopian ethnic groups. We estimated the ages of low/non-expresser CYP3A5 alleles using a linked microsatellite and assuming a step-wise mutation model of evolution. Finally, we examined a hypothesis that CYP3A5 is important in salt retention adaptation by performing correlations with ecological data relating to aridity for the present day, 10,000 and 50,000 years ago. Results: We estimate that similar to 43% of individuals within our African dataset express CYP3A5, which is lower than previous independent estimates for the region. We found significant intra-African variability in CYP3A5 expression phenotypes. Within Africa the highest frequencies of high-activity alleles were observed in equatorial and Niger-Congo speaking populations. Ethiopian allele frequencies were intermediate between those of other sub-Saharan African and non-African groups. Re-sequencing of CYP3A5 identified few additional variants likely to affect CYP3A5 expression. We estimate the ages of CYP3A5*3 as similar to 76,400 years and CYP3A5*6 as similar to 218,400 years. Finally we report that global CYP3A5 expression levels correlated significantly with aridity measures for 10,000 [Spearmann's Rho= -0.465, p=0.004] and 50,000 years ago [Spearmann's Rho= -0.379, p=0.02]. Conclusions: Significant intra-African diversity at the CYP3A5 gene is likely to contribute to multiple pharmacogenetic profiles across the continent. Significant correlations between CYP3A5 expression phenotypes and aridity data are consistent with a hypothesis that the enzyme is important in salt-retention adaptation.

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  • 277.
    Baison, John
    et al.
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Parallellvagen 21, S-90736 Umea, Sweden.
    Vidalis, Amaryllis
    Tech Univ Munich, Sect Populat Epigenet & Epigen, Ctr Life & Food Sci Weihenstephan, Lichtenbergstr 2a, D-85748 Munich, Germany.
    Zhou, Linghua
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Parallellvagen 21, S-90736 Umea, Sweden.
    Chen, Zhi-Qiang
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Parallellvagen 21, S-90736 Umea, Sweden.
    Li, Zitong
    Univ Helsinki, Dept Biosci, Ecol Genet Res Unit, POB 65, FI-00014 Helsinki, Finland.
    Sillanpää, Mikko J.
    Univ Oulu, Dept Math Sci, Bioctr Oulu, Pentti Kaiteran Katu 1, Oulu, Finland.
    Bernhardsson, Carolina
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Parallellvagen 21, S-90736 Umea, Sweden;Umea Univ, Dept Ecol & Environm Sci, Linnaeus Vag 4-6, S-90736 Umea, Sweden.
    Scofield, Douglas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Forsberg, Nils
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Parallellvagen 21, S-90736 Umea, Sweden.
    Grahn, Thomas
    RISE Bioecon, Drottning Kristinas Vag 61, SE-11486 Stockholm, Sweden.
    Olsson, Lars
    RISE Bioecon, Drottning Kristinas Vag 61, SE-11486 Stockholm, Sweden.
    Karlsson, Bo
    Skogforsk, Ekebo 2250, SE-26890 Svalov, Sweden.
    Wu, Harry
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Parallellvagen 21, S-90736 Umea, Sweden.
    Ingvarsson, Pär K:
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology. Umea Univ, Dept Ecol & Environm Sci, Linnaeus Vag 4-6, S-90736 Umea, Sweden.
    Lundqvist, Sven-Olof
    RISE Bioecon, Drottning Kristinas Vag 61, SE-11486 Stockholm, Sweden;IIC, Rosenlundsgatan 48B, SE-11863 Stockholm, Sweden.
    Niittylä, Totte
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Parallellvagen 21, S-90736 Umea, Sweden.
    Garcia-Gil, M. Rosario
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Parallellvagen 21, S-90736 Umea, Sweden.
    Genome-wide association study identified novel candidate loci affecting wood formation in Norway spruce2019In: The Plant Journal, ISSN 0960-7412, E-ISSN 1365-313X, Vol. 100, no 1, p. 83-100Article in journal (Refereed)
    Abstract [en]

    Norway spruce is a boreal forest tree species of significant ecological and economic importance. Hence there is a strong imperative to dissect the genetics underlying important wood quality traits in the species. We performed a functional genome-wide association study (GWAS) of 17 wood traits in Norway spruce using 178 101 single nucleotide polymorphisms (SNPs) generated from exome genotyping of 517 mother trees. The wood traits were defined using functional modelling of wood properties across annual growth rings. We applied a Least Absolute Shrinkage and Selection Operator (LASSO-based) association mapping method using a functional multilocus mapping approach that utilizes latent traits, with a stability selection probability method as the hypothesis testing approach to determine a significant quantitative trait locus. The analysis provided 52 significant SNPs from 39 candidate genes, including genes previously implicated in wood formation and tree growth in spruce and other species. Our study represents a multilocus GWAS for complex wood traits in Norway spruce. The results advance our understanding of the genetics influencing wood traits and identifies candidate genes for future functional studies.

  • 278. Bakker, Jan P.
    et al.
    Hoffmann, Frank
    Ozinga, Wim A.
    Rosén, Eje
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Shading results in depletion of the soil seed bank2014In: Nordic Journal of Botany, ISSN 0107-055X, E-ISSN 1756-1051, Vol. 32, no 5, p. 674-679Article in journal (Refereed)
    Abstract [en]

    To what extent is the decline of characteristic dry alvar species related to the decline in the soil seed bank during scrub encroachment? We recorded the number of flower stems in the vegetation in relation to light attenuation along an encroachment series progressing from open alvar through small gaps inside dense scrub of Juniperus communis (cover of 60%) to intact dense scrub (cover of 100%) on the island of oland, Sweden. This measurement of potential reproduction (number of flower stems) was then compared to the number of species in the soil seed bank at each site along the alvar encroachment series. Scrub encroachment results in light attenuation between and under the shrubs. The total number of flower stems averaged over all species was similar between gaps and open alvar, but that of alvar species was significantly lower in the gaps, indicating that light attenuation could reduce their seed set. Shading in gaps is related to depletion of the soil seed bank and loss of alvar species, particularly those that do not form a persistent soil seed bank.

  • 279. Bakker, Jan P.
    et al.
    Rosén, Eje
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ozinga, Wim A.
    Bretfeld, Mario
    Feldt, Tobias
    Stahl, Julia
    Long-term effects of scrub clearance and litter removal on the re-establishment of dry alvar grassland species2012In: Annales Botanici Fennici, ISSN 0003-3847, E-ISSN 1797-2442, Vol. 49, no 1-2, p. 21-30Article in journal (Refereed)
    Abstract [en]

    Many characteristic dry alvar grassland species disappear after cessation of livestock grazing as a result of encroachment by Juniperus communis. We studied the re-establishment of these species after scrub clearance with and without the removal of the layer of litter and mosses in long-term (14 years) permanent plots. Most of the species belonging to the community species pool of dry alvar grassland species before clearance were found in permanent plots between 2 and 14 years after the clearance. A large part originated from vegetative spread of already occurring species in the established vegetation in the surroundings. Only a small part of the long-term persistent soil seed bank resulted in the re-establishment of alvar species. There was no significant difference in the traits soil seed bank, seed weight and long-distance dispersal by wind, dung or fur of animals of established and non-established species. Removal of litter and mosses positively affected the re-establishment of alvar species.

  • 280.
    Balanzategui, Daniel
    et al.
    GFZ German Res Ctr Geosci, Potsdam, Germany.;Humboldt Univ, Inst Geog, Berlin, Germany.;DAI German Archaeol Inst, Dept Nat Sci, Berlin, Germany..
    Nordhauss, Henry
    GFZ German Res Ctr Geosci, Potsdam, Germany..
    Heinrich, Ingo
    GFZ German Res Ctr Geosci, Potsdam, Germany.;Humboldt Univ, Inst Geog, Berlin, Germany.;DAI German Archaeol Inst, Dept Nat Sci, Berlin, Germany..
    Biondi, Franco
    Univ Nevada, Dept Nat Resources & Environm Sci, DendroLab, Reno, NV 89557 USA..
    Miley, Nicholas
    Univ Nevada, Dept Nat Resources & Environm Sci, DendroLab, Reno, NV 89557 USA..
    Hurley, Alexander G.
    GFZ German Res Ctr Geosci, Potsdam, Germany..
    Ziaco, Emanuele
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. GFZ German Res Ctr Geosci, Potsdam, Germany.
    Wood Anatomy of Douglas-Fir in Eastern Arizona and Its Relationship With Pacific Basin Climate2021In: Frontiers in Plant Science, E-ISSN 1664-462X, Vol. 12, article id 702442Article in journal (Refereed)
    Abstract [en]

    Dendroclimatic reconstructions, which are a well-known tool for extending records of climatic variability, have recently been expanded by using wood anatomical parameters. However, the relationships between wood cellular structures and large-scale climatic patterns, such as El Nino-Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO), are still not completely understood, hindering the potential for wood anatomy as a paleoclimatic proxy. To better understand the teleconnection between regional and local climate processes in the western United States, our main objective was to assess the value of these emerging tree-ring parameters for reconstructing climate dynamics. Using Confocal Laser Scanning Microscopy, we measured cell lumen diameter and cell wall thickness (CWT) for the period 1966 to 2015 in five Douglas-firs [Pseudotsuga menziesii (Mirb.) Franco] from two sites in eastern Arizona (United States). Dendroclimatic analysis was performed using chronologies developed for 10 equally distributed sectors of the ring and daily climatic records to identify the strongest climatic signal for each sector. We found that lumen diameter in the first ring sector was sensitive to previous fall-winter temperature (September 25(th) to January 23(rd)), while a precipitation signal (October 27(th) to February 13(th)) persisted for the entire first half of the ring. The lack of synchronous patterns between trees for CWT prevented conducting meaningful climate-response analysis for that anatomical parameter. Time series of lumen diameter showed an anti-phase relationship with the Southern Oscillation Index (a proxy for ENSO) at 10 to 14year periodicity and particularly in 1980-2005, suggesting that chronologies of wood anatomical parameters respond to multidecadal variability of regional climatic modes. Our findings demonstrate the potential of cell structural characteristics of southwestern United States conifers for reconstructing past climatic variability, while also improving our understanding of how large-scale ocean-atmosphere interactions impact local hydroclimatic patterns.

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  • 281. Balding, David
    et al.
    Weale, Michael
    Richards, Michael
    Thomas, Mark
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Genetic and isotopic analysis and the UK border agency2010In: Significance, Vol. 7, no 2, p. 58-61Article in journal (Refereed)
  • 282.
    Balk, Pauline
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Removal of organic matter by NaOCl: An improved method to characterize organic microbial food sources2024Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
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  • 283.
    Balmonte, John Paul
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology. Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27599 USA.
    Buckley, Andrew
    Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27599 USA.
    Hoarfrost, Adrienne
    Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27599 USA.
    Ghobrial, Sherif
    Univ New Hampshire, Inst Study Earth Oceans & Space, Durham, NH 03824 USA.
    Ziervogel, Kai
    Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27599 USA.
    Teske, Andreas
    Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27599 USA.
    Arnosti, Carol
    Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27599 USA.
    Community structural differences shape microbial responses to high molecular weight organic matter2019In: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 21, no 2, p. 557-571Article in journal (Refereed)
    Abstract [en]

    The extent to which differences in microbial community structure result in variations in organic matter (OM) degradation is not well understood. Here, we tested the hypothesis that distinct marine microbial communities from North Atlantic surface and bottom waters would exhibit varying compositional succession and functional shifts in response to the same pool of complex high molecular weight (HMW-OM). We also hypothesized that microbial communities would produce a broader spectrum of enzymes upon exposure to HMW-OM, indicating a greater potential to degrade these compounds than reflected by initial enzymatic activities. Our results show that community succession in amended mesocosms was congruent with cell growth, increased bacterial production and most notably, with substantial shifts in enzymatic activities. In all amended mesocosms, closely related taxa that were initially rare became dominant at time frames during which a broader spectrum of active enzymes were detected compared to initial timepoints, indicating a similar response among different communities. However, succession on the whole-community level, and the rates, spectra and progression of enzymatic activities, reveal robust differences among distinct communities from discrete water masses. These results underscore the crucial role of rare bacterial taxa in ocean carbon cycling and the importance of bacterial community structure for HMW-OM degradation.

  • 284.
    Balmonte, John Paul
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology. Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27515 USA.
    Hasler-Sheetal, Harald
    Univ Southern Denmark, Dept Biol, Odense, Denmark.
    Glud, Ronnie N.
    Univ Southern Denmark, Dept Biol, Odense, Denmark;Tokyo Univ Marine Sci & Technol, Dept Ocean & Environm Sci, Tokyo, Japan.
    Andersen, Thorbjörn J.
    Univ Copenhagen, Dept Geosci & Nat Resources Management, Sect Geog, Copenhagen, Denmark.
    Sejr, Mikael K.
    Aarhus Univ, Arctic Res Ctr, Aarhus, Denmark;Aarhus Univ, Dept Biosci, Silkeborg, Denmark.
    Middelboe, Mathias
    Univ Copenhagen, Marine Biol Sect, Helsingor, Denmark.
    Teske, Andreas
    Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27515 USA.
    Arnosti, Carol
    Univ N Carolina, Dept Marine Sci, Chapel Hill, NC 27515 USA.
    Sharp contrasts between freshwater and marine microbial enzymatic capabilities, community composition, and DOM pools in a NE Greenland fjord2020In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 65, no 1, p. 77-95Article in journal (Refereed)
    Abstract [en]

    Increasing glacial discharge can lower salinity and alter organic matter (OM) supply in fjords, but assessing the biogeochemical effects of enhanced freshwater fluxes requires understanding of microbial interactions with OM across salinity gradients. Here, we examined microbial enzymatic capabilities-in bulk waters (nonsize-fractionated) and on particles (>= 1.6 mu m)-to hydrolyze common OM constituents (peptides, glucose, polysaccharides) along a freshwater-marine continuum within Tyrolerfjord-Young Sound. Bulk peptidase activities were up to 15-fold higher in the fjord than in glacial rivers, whereas bulk glucosidase activities in rivers were twofold greater, despite fourfold lower cell counts. Particle-associated glucosidase activities showed similar trends by salinity, but particle-associated peptidase activities were up to fivefold higher-or, for several peptidases, only detectable-in the fjord. Bulk polysaccharide hydrolase activities also exhibited freshwater-marine contrasts: xylan hydrolysis rates were fivefold higher in rivers, while chondroitin hydrolysis rates were 30-fold greater in the fjord. Contrasting enzymatic patterns paralleled variations in bacterial community structure, with most robust compositional shifts in river-to-fjord transitions, signifying a taxonomic and genetic basis for functional differences in freshwater and marine waters. However, distinct dissolved organic matter (DOM) pools across the salinity gradient, as well as a positive relationship between several enzymatic activities and DOM compounds, indicate that DOM supply exerts a more proximate control on microbial activities. Thus, differing microbial enzymatic capabilities, community structure, and DOM composition-interwoven with salinity and water mass origins-suggest that increased meltwater may alter OM retention and processing in fjords, changing the pool of OM supplied to coastal Arctic microbial communities.

  • 285.
    Balmonte, John Paul
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology. Univ North Carolina Chapel Hill, Dept Marine Sci, Chapel Hill, NC 27514 USA.;Univ Southern Denmark, Dept Biol, HADAL & Nordcee, Odense, Denmark..
    Simon, Meinhard
    Carl von Ossietzky Univ Oldenburg, Inst Chem & Biol Marine Environm, Oldenburg, Germany..
    Giebel, Helge-Ansgar
    Carl von Ossietzky Univ Oldenburg, Inst Chem & Biol Marine Environm, Oldenburg, Germany..
    Arnosti, Carol
    Univ North Carolina Chapel Hill, Dept Marine Sci, Chapel Hill, NC 27514 USA..
    A sea change in microbial enzymes: Heterogeneous latitudinal and depth-related gradients in bulk water and particle-associated enzymatic activities from 30 degrees S to 59 degrees N in the Pacific Ocean2021In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 66, no 9, p. 3489-3507Article in journal (Refereed)
    Abstract [en]

    Heterotrophic microbes initiate the degradation of high molecular weight organic matter using extracellular enzymes. Our understanding of differences in microbial enzymatic capabilities, especially among particle-associated taxa and in the deep ocean, is limited by a paucity of hydrolytic enzyme activity measurements. Here, we measured the activities of a broad range of hydrolytic enzymes (glucosidases, peptidases, polysaccharide hydrolases) in epipelagic to bathypelagic bulk water (nonsize-fractionated), and on particles (>= 3 mu m) along a 9800 km latitudinal transect from 30 degrees S in the South Pacific to 59 degrees N in the Bering Sea. Individual enzyme activities showed heterogeneous latitudinal and depth-related patterns, with varying biotic and abiotic correlates. With increasing latitude and decreasing temperature, lower laminarinase activities sharply contrasted with higher leucine aminopeptidase (leu-AMP) and chondroitin sulfate hydrolase activities in bulk water. Endopeptidases (chymotrypsins, trypsins) exhibited patchy spatial patterns, and their activities can exceed rates of the widely measured exopeptidase, leu-AMP. Compared to bulk water, particle-associated enzymatic profiles featured a greater relative importance of endopeptidases, as well as a broader spectrum of polysaccharide hydrolases in some locations, and latitudinal and depth-related trends that are likely consequences of varying particle fluxes. As water depth increased, enzymatic spectra on particles and in bulk water became narrower, and diverged more from one another. These distinct latitudinal and depth-related gradients of enzymatic activities underscore the biogeochemical consequences of emerging global patterns of microbial community structure and function, from surface to deep waters, and among particle-associated taxa.

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  • 286.
    Balslev, Henrik
    et al.
    Aarhus Univ, Dept Biosci, Sect Ecoinformat & Biodivers, DK-8000 Aarhus, Denmark.
    Kristiansen, Soren M.
    Aarhus Univ, Dept Geosci, DK-8000 Aarhus, Denmark.
    Muscarella, Robert
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Aarhus Univ, Dept Biosci, Sect Ecoinformat & Biodivers, DK-8000 Aarhus, Denmark.
    Palm community transects and soil properties in western Amazonia2019In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 100, no 12, article id e02841Article in journal (Refereed)
    Abstract [en]

    Western Amazonia is a global biodiversity hotspot that encompasses extensive variation in geologic, climatic, and biotic features. Palms (Arecaceae) are among the most diverse and iconic groups of plants in the region with more than 150 species that exhibit extraordinary variation of geographical distributions, regional abundance patterns, and life history strategies and growth forms, and provide myriad ecosystem services. Understanding the ecological and evolutionary drivers that underpin palm distribution and abundance patterns may shed light on the evolution and ecology of the tropical forest biomes more generally. Edaphic conditions, in particular, are increasingly recognized as critical drivers of tropical plant diversity and distributions but data deficiencies inhibit our understanding of plant-soil relationships at broad scales, especially in the tropics. We present data from 546, 0.25-ha (5 x 500 m) georeferenced transects located throughout western Amazonia where all individual palms were identified, counted, and assigned to a life-history stage. Several environmental covariates were recorded along each transect and surface soil samples were collected from multiple points in N = 464 of transects. Altogether, the transects include 532,602 individuals belonging to 135 species. Variation among transects in terms of palm species richness and abundance is associated with major habitat types and soil properties. The soil properties including pH, acidity, all macronutrients for all samples, and texture, carbon, nitrogen, and micronutrients for some transects vary substantially across the study area, providing insight to broad-scale variation of tropical surface soils. The data provided here will help advance our understanding of plant distributions and abundance patterns, and associations with soil conditions. No copyright restrictions are associated with this data set but please cite this paper if data are used for publication.

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  • 287.
    Baltazar-Soares, Miguel
    et al.
    Univ Turku, Dept Biol, Turku 20500, Finland..
    Karell, Patrik
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Lund Univ, Dept Biol, Sect Evolutionary Ecol, Lund, Sweden.;Nov Univ Appl Sci, Dept Bioecon, Ekenas, Finland..
    Wright, Dominic
    Linköping Univ, IFM Biol, Linköping, Sweden..
    Nilsson, Jan-Åke
    Lund Univ, Dept Biol, Sect Evolutionary Ecol, Lund, Sweden..
    Brommer, Jon E.
    Univ Turku, Dept Biol, Turku 20500, Finland..
    Genomic basis of melanin-associated phenotypes suggests colour-specific environmental adaptations in tawny owls2024In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 33, no 4, article id e17247Article in journal (Refereed)
    Abstract [en]

    Feathers comprise a series of evolutionary innovations but also harbour colour, a key biological trait known to co-vary with life history or complex traits. Those relationships are particularly true in melanin-based pigmentation species due to known pleiotropic effects of the melanocortin pathway - originating from melanin-associated phenotypes. Here, we explore the molecular basis of melanin colouration and expected co-variation at the molecular level in the melanin-based, colour polymorphic system of the tawny owl (Strix aluco). An extensive body of literature has revealed that grey and brown tawny owl colour morphs differ in a series of life history and behavioural traits. Thus, it is plausible to expect co-variation also at molecular level between colour morphs. To investigate this possibility, we assembled the first draft genome of the species against which we mapped ddRADseq reads from 220 grey and 150 brown morphs - representing 10 years of pedigree data from a population in Southern Finland - and explored genome-wide associations with colour phenotype. Our results revealed putative molecular signatures of cold adaptation strongly associated with the grey phenotype, namely, a non-synonymous substitution in MCHR1, plus 2 substitutions in non-coding regions of FTCD and FAM135A whose genotype combinations obtained a predictive power of up to 100% (predicting grey colour). These suggest a molecular basis of cold environment adaptations predicted to be grey-morph specific. Our results potentially reveal part of the molecular machinery of melanin-associated phenotypes and provide novel insights towards understanding the functional genomics of colour polymorphism in melanin-based pigmented species.

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    fulltext
  • 288.
    Barbosa, Pedro M.
    et al.
    Univ Calif Santa Barbara, Earth Res Inst, Santa Barbara, CA 93106 USA; Univ Fed Rio de Janeiro, Inst Biol, Dept Ecol, Rio De Janeiro, Brazil.
    Melack, John M.
    Univ Calif Santa Barbara, Earth Res Inst, Santa Barbara, CA 93106 USA.
    Amaral, João H. F.
    Univ Calif Santa Barbara, Earth Res Inst, Santa Barbara, CA 93106 USA; Inst Nacl de Pesquisas da Amazonia, Lab Ecossistemas Aquat, Manaus, Amazonas, Brazil.
    Linkhorst, Annika
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Forsberg, Bruce R.
    Inst Nacl de Pesquisas da Amazonia, Lab Ecossistemas Aquat, Manaus, Amazonas, Brazil; Vermont Dept Environm Conservat, Montpelier, VT USA.
    Large Seasonal and Habitat Differences in Methane Ebullition on the Amazon Floodplain2021In: Journal of Geophysical Research - Biogeosciences, ISSN 2169-8953, E-ISSN 2169-8961, Vol. 126, no 7, article id e2020JG005911Article in journal (Refereed)
    Abstract [en]

    Tropical floodplains are an important source of methane (CH4) to the atmosphere, and ebullitive fluxes are likely to be important. We report direct measurements of CH4 ebullition in common habitats on the Amazon floodplain over two years based on floating chambers that allowed detection of bubbles, and submerged bubble traps. Ebullition was highly variable in space and time. Of the 840 floating chamber measurements (equivalent to 8,690 min of 10-min deployments), 22% captured bubbles. Ebullitive CH4 fluxes, measured using bubble traps deployed for a total of approximately 230 days, ranged from 0 to 109 mmol CH4 m−2 d−1, with a mean of 4.4 mmol CH4 m−2 d−1. During falling water, a hydroacoustic echosounder detected bubbles in 24% of the 70-m segments over 34 km. Ebullitive flux increased as the water level fell faster during falling water periods. In flooded forests, highest ebullitive fluxes occurred during falling water, while in open water and herbaceous plant habitats, higher ebullitive fluxes were measured during low water periods. The contribution of diffusive plus ebullitive CH4 flux represented by ebullition varied from 1% (high and rising water in open water of the lake) to 93% (falling water in flooded forests) based on bubble traps. Combining ebullitive and diffusive fluxes among habitats in relation to variations in water depth and areal coverage of aquatic habitats provides the basis for improved floodplain-wide estimates of CH4 evasion.

    Plain Language Summary

    Methane is a trace gas that contributes to global warming, and wetlands are major natural sources. High concentrations of methane in sediments can lead to large releases to the atmosphere via bubbling (called ebullition). The Amazon basin is known to be an important source of CH4 to the atmosphere. We measured CH4 ebullition over two years in flooded forest, macrophytes and open water habitats in an Amazon floodplain using floating chambers that allowed detection of bubbles, and bubble traps; we also used hydroacoustics to detect bubbles in the water column. We found high spatial and temporal variability in all habitats, with ebullitive fluxes tending to be higher when water level was low or falling. While ebullition was often the major route of evasion of methane to the atmosphere, it varied from only about 1% to 93% of the diffusive plus ebullitive flux. The episodic nature and spatial variations of ebullition introduce considerable uncertainty in estimates of ebullitive CH4 flux. Our results have important implications for the regionalization of CH4 fluxes for Amazon floodplains and inland waters elsewhere, and emphasize the inter-related temporal and spatial variations in habitats and fluxes especially in aquatic systems with large seasonal variations in extent.

  • 289.
    Barnaby, Jonathan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology.
    Cooperative Breeding in the Southern Anteater-Chat: Sexual Disparity, Survival and Dispersal2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Group-living sets the scene for complex social behaviours such as cooperative breeding, and exploring the factors that shape group-living is crucial in understanding these behaviours. This thesis explores the ecology of a population of the facultative cooperative breeding southern anteater-chat (Myrmecocichla formicivora), a group-living bird species endemic to southern Africa. It reveals a breeding system based around a breeding pair and up to three auxiliary males. Despite equal numbers of males and females produced as fledglings there was a surplus of adult males, which remained philopatric. Dispersal was strongly female biased. Females dispersed within their first year, they dispersed further than males, and they lost the benefits of the natal site. The sex skew in the population suggested that these factors drive differential mortality, with juvenile females having much lower annual survival than juvenile males. Adult survival was higher, with female survival only slightly lower than male survival. Dispersal distances suggested that males selected the breeding location, nearer to their natal site. There was no evidence of surplus non-breeding females. On the loss of a breeding female there was no replacement until new females entered the population, yet if a breeding male disappeared the female promptly re-paired with a male from another group. There was no indication of birds floating in the population, and if males were orphaned or widowed they joined other groups as unrelated helpers in preference to floating. There was no sign of inter-group or individual aggression among chats, and unrelated helpers were peacefully accepted into groups, suggesting mutual benefits. In fact all birds in a group helped raise offspring of the breeding pair, and groups with more helpers fledged more offspring, which implies that both direct and indirect fitness benefits can be gained through joining a group and helping. There was surprisingly little inheritance of breeding position by auxiliaries, and strikingly low levels of extra-pair paternity. This study suggests that the Southern anteater-chat group structure arises through male philopatry due to a shortage of breeding females, the benefits of remaining on the natal site and helping, and the potentially high costs of living alone.

    List of papers
    1. Group-living in the southern anteater-chat Myrmecocichla formicivora.
    Open this publication in new window or tab >>Group-living in the southern anteater-chat Myrmecocichla formicivora.
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Group-living sets the scene for complex social behaviours such as cooperative breeding, and exploring the factors that shape group-living is crucial in understanding these behaviours. Here we describe some aspects of the ecology of a population of the facultative cooperative breeding southern anteater-chat (Myrmecocichla formicivora), a group living bird species endemic to southern Africa. We used data from a four year study of individually marked birds, with pedigrees completed using microsatellite genotyping. Southern anteater-chats live in groups of 2-5 individuals - a breeding pair and up to three additional none-breeders. These auxiliary birds were either retained offspring or unrelated individuals, and all birds in a group assisted by feeding at the nest. Our population had a skewed sex ratio of approximately 58% males to 42% females, yet the sex ratio of fledglings was equal, suggesting sex-biased mortality. Helpers were predominantly retained male offspring; however 21% of helpers were unrelated to either of the breeding pair. Southern anteater-chats appear to be non-territorial, with an apparent lack of aggression both within and between groups. Our study confirms that the southern anteater-chat is a facultative cooperative breeder, with both pair breeders and groups with helpers capable of fledging youngsters. We provide evidence suggesting that the breeding system of the southern anteater-chat is based on prompt female dispersal, and male philopatry due to an apparent shortage of mates, potential benefits of the natal site and possible high costs of floating. It appears that ecological constraints promoting delayed dispersal are reinforced by benefits gained from remaining philopatric.

    Keywords
    Southern anteater-chat, cooperative breeding, social evolution, behavioural ecology, delayed dispersal, family living, Africa
    National Category
    Evolutionary Biology
    Research subject
    Biology with specialization in Population Biology
    Identifiers
    urn:nbn:se:uu:diva-179071 (URN)
    Available from: 2012-08-13 Created: 2012-08-07 Last updated: 2012-09-05
    2. Sex specific survival in the southern anteater-chat Mymecocichla formicivora.
    Open this publication in new window or tab >>Sex specific survival in the southern anteater-chat Mymecocichla formicivora.
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Survival is a key factor behind life-history variation both between and within species. It is also a major influence on sociality in species which delay dispersal and live in family groups. Knowledge of differential survival rates between males and females and juveniles and adults give insights into the costs and benefits of different behavioural and life-history strategies. Here we investigate patterns of survival in a population of the southern anteater-chat (Myrmecocichla formicivora), a facultative cooperatively breeding passerine of southern Africa. Using data from a 9-year mark-capture-recapture study, we examined juvenile and adult sex related variation in survival, and the role of environmental variables (rainfall, temperature) for survival patterns in the population. Annual adult survival probability (mean ± SE) was 0.71 ± 0.03 for males and 0.60 ± 0.04 for females. Juvenile survival was lower for each sex, with juvenile female survival (0.36 ± 0.04) being 35% lower than juvenile male survival (0.55 ± 0.04). Using these estimates we calculated the mean life span (MLS) in years for male southern anteater-chat to be 4.0 ± 0.7, considerably higher than for females at 2.0 ± 0.4. These figures closely matched the population-age structure of the study area, and could explain the high male biased sex skew of adult birds in this population. Higher annual mean temperature was associated with higher survival, whereas higher annual rainfall was associated with lower survival for both sex and age classes. Female survival, particularly female juvenile survival, may be reduced due to prompt dispersal and longer dispersal distances, and the additional costs of breeding early in life. Differential survival can promote male philopatry and this in turn could well encourage the cooperative breeding we see in the southern anteater-chat.

    Keywords
    Southern anteater-chat, cooperative breeding, social evolution, behavioural ecology, delayed dispersal, family living, Africa
    National Category
    Evolutionary Biology
    Research subject
    Biology with specialization in Population Biology
    Identifiers
    urn:nbn:se:uu:diva-179072 (URN)
    Available from: 2012-08-13 Created: 2012-08-07 Last updated: 2012-09-05
    3. The rarer sex - female natal dispersal and breeder replacement in the southern anteater-chat Myrmecocichla formicivora.
    Open this publication in new window or tab >>The rarer sex - female natal dispersal and breeder replacement in the southern anteater-chat Myrmecocichla formicivora.
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Sex biased dispersal is a crucial factor in understanding the mechanism of family dynamics in many cooperative breeders. Female biased dispersal occurs in many cooperatively breeding birds. It is often associated with females dispersing earlier and further, and a male biased sex skew in the population. Here we investigated female dispersal in the southern anteater-chat, a facultative cooperatively breeding passerine of southern Africa. Our study population had a male biased sex skew, and females had lower annual survival than males. Dispersal was strongly female biased, with females dispersing within their first year whereas many males remained philopatric beyond the next breeding season. Breeding females were on average younger than breeding males, and also dispersed further. Each breeding group contained only one female. No females were found floating in the population, and all females were associated with one or more males in a breeding group. It appears that all females disperse in their first year directly to a breeding position. If a female disappeared in the breeding season they were not replaced until new females matured and dispersed the following season, yet if a male breeder disappeared during the breeding season he was almost immediately replaced, indicating that there are no surplus females.

    Keywords
    Southern anteater-chat, cooperative breeding, social evolution, behavioural ecology, delayed dispersal, family living, Africa
    National Category
    Evolutionary Biology
    Research subject
    Biology with specialization in Population Biology
    Identifiers
    urn:nbn:se:uu:diva-179073 (URN)
    Available from: 2012-08-13 Created: 2012-08-07 Last updated: 2012-09-05
    4. From helping to breeding – male choice in the southern anteater-chats Myrmecocichla formicivora.
    Open this publication in new window or tab >>From helping to breeding – male choice in the southern anteater-chats Myrmecocichla formicivora.
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    Dispersal choice is important in understanding population structure and dynamics. Here we examine male choice in the facultative cooperative breeding southern anteater-chat Myrmecocichla formicivora based on a four year study in South Africa. The sex ratio in our study population was male biased, with many males remaining philopatric. All groups consisted of one or more adult males associated with one adult female. We found a significant positive effect of auxiliary number on group productivity (both number of young fledged, and first year survival), while controlling for potentially confounding variables (territory and breeder identity). The majority of auxiliaries, 54%, were related to both birds in the breeding pair, with another 25% related to one member of the pair, and 21% related to neither of the breeders. There was no evidence of males floating within our study population, and it appears that if males lose their family due to mortality they join other groups as unrelated non-breeding auxiliaries rather than float. No aggression was observed between individual southern anteater-chats, and unrelated group members helped rear offspring in the group they had joined. Despite the presence of, and helping by unrelated group members there was very little evidence of breeding position inheritance (1/24 auxiliaries unrelated to the breeding female) or extra-pair paternity (2.4% of fledglings). This study suggests that the southern anteater-chat group structure arises through male philopatry due to a lack of breeding females and potentially high costs of living alone.

    Keywords
    Southern anteater-chat, cooperative breeding, social evolution, behavioural ecology, delayed dispersal, family living, Africa
    National Category
    Evolutionary Biology
    Research subject
    Biology with specialization in Population Biology
    Identifiers
    urn:nbn:se:uu:diva-179074 (URN)
    Available from: 2012-08-13 Created: 2012-08-07 Last updated: 2012-09-05
    5. Development of a suit of microsatellite markers for the southern anteater-chat Myrmecocichla formicivora.
    Open this publication in new window or tab >>Development of a suit of microsatellite markers for the southern anteater-chat Myrmecocichla formicivora.
    (English)Manuscript (preprint) (Other academic)
    Abstract [en]

    We tested the cross amplification of 37 microsatellite markers for their suitability in genotyping the southern anteater-chat Myrmecocichla formicivora, an opportunistic cooperatively breeding passerine bird endemic to southern Africa. Fourteen microsatellite markers were identified as having suitable characteristics, with minor deviation from Hardy-Weinberg equilibrium and little evidence of null alleles. These 14 Primer pairs were combined in 4 multiplexes and run on 183 individual samples from our study population of southern anteater-chat on Benfontein Nature Reserve, near Kimberley in central South Africa. The loci ranged from 3-34 alleles per locus, and observed heterozygosity ranged from 0.45 -0.93. We then tested these 14 microsatellites for their use in examining paternity in a population of southern anteater-chat being studied on Benfontein Nature Reserve, near Kimberley in South Africa. Of the population of 183 individuals (the 2011 population) 93% of the offspring could be allocated a mother, 97% a father, and 87% a parent pair with 95% confidence. The remainder could be allocated at the 80% confidence level. Where mothers could be assigned from observations this was in 100% agreement with the microsatellite results, giving us good support for the accurate assignment of parentage in our population.

    Keywords
    Southern anteater-chat, cooperative breeding, social evolution, microsatellites, genotyping, cross-amplification, behavioural ecology, delayed dispersal, family living, Africa
    National Category
    Evolutionary Biology
    Research subject
    Biology with specialization in Population Biology
    Identifiers
    urn:nbn:se:uu:diva-179075 (URN)
    Available from: 2012-08-13 Created: 2012-08-07 Last updated: 2012-09-05
    Download full text (pdf)
    fulltext
  • 290.
    Barnaby, Jonathan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology.
    Ekman, Jan
    From helping to breeding – male choice in the southern anteater-chats Myrmecocichla formicivora.Manuscript (preprint) (Other academic)
    Abstract [en]

    Dispersal choice is important in understanding population structure and dynamics. Here we examine male choice in the facultative cooperative breeding southern anteater-chat Myrmecocichla formicivora based on a four year study in South Africa. The sex ratio in our study population was male biased, with many males remaining philopatric. All groups consisted of one or more adult males associated with one adult female. We found a significant positive effect of auxiliary number on group productivity (both number of young fledged, and first year survival), while controlling for potentially confounding variables (territory and breeder identity). The majority of auxiliaries, 54%, were related to both birds in the breeding pair, with another 25% related to one member of the pair, and 21% related to neither of the breeders. There was no evidence of males floating within our study population, and it appears that if males lose their family due to mortality they join other groups as unrelated non-breeding auxiliaries rather than float. No aggression was observed between individual southern anteater-chats, and unrelated group members helped rear offspring in the group they had joined. Despite the presence of, and helping by unrelated group members there was very little evidence of breeding position inheritance (1/24 auxiliaries unrelated to the breeding female) or extra-pair paternity (2.4% of fledglings). This study suggests that the southern anteater-chat group structure arises through male philopatry due to a lack of breeding females and potentially high costs of living alone.

  • 291.
    Barnaby, Jonathan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology.
    Ekman, Jan
    The rarer sex - female natal dispersal and breeder replacement in the southern anteater-chat Myrmecocichla formicivora.Manuscript (preprint) (Other academic)
    Abstract [en]

    Sex biased dispersal is a crucial factor in understanding the mechanism of family dynamics in many cooperative breeders. Female biased dispersal occurs in many cooperatively breeding birds. It is often associated with females dispersing earlier and further, and a male biased sex skew in the population. Here we investigated female dispersal in the southern anteater-chat, a facultative cooperatively breeding passerine of southern Africa. Our study population had a male biased sex skew, and females had lower annual survival than males. Dispersal was strongly female biased, with females dispersing within their first year whereas many males remained philopatric beyond the next breeding season. Breeding females were on average younger than breeding males, and also dispersed further. Each breeding group contained only one female. No females were found floating in the population, and all females were associated with one or more males in a breeding group. It appears that all females disperse in their first year directly to a breeding position. If a female disappeared in the breeding season they were not replaced until new females matured and dispersed the following season, yet if a male breeder disappeared during the breeding season he was almost immediately replaced, indicating that there are no surplus females.

  • 292.
    Barnaby, Jonathan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology.
    Fletcher, Kevin
    Ekman, Jan
    Development of a suit of microsatellite markers for the southern anteater-chat Myrmecocichla formicivora.Manuscript (preprint) (Other academic)
    Abstract [en]

    We tested the cross amplification of 37 microsatellite markers for their suitability in genotyping the southern anteater-chat Myrmecocichla formicivora, an opportunistic cooperatively breeding passerine bird endemic to southern Africa. Fourteen microsatellite markers were identified as having suitable characteristics, with minor deviation from Hardy-Weinberg equilibrium and little evidence of null alleles. These 14 Primer pairs were combined in 4 multiplexes and run on 183 individual samples from our study population of southern anteater-chat on Benfontein Nature Reserve, near Kimberley in central South Africa. The loci ranged from 3-34 alleles per locus, and observed heterozygosity ranged from 0.45 -0.93. We then tested these 14 microsatellites for their use in examining paternity in a population of southern anteater-chat being studied on Benfontein Nature Reserve, near Kimberley in South Africa. Of the population of 183 individuals (the 2011 population) 93% of the offspring could be allocated a mother, 97% a father, and 87% a parent pair with 95% confidence. The remainder could be allocated at the 80% confidence level. Where mothers could be assigned from observations this was in 100% agreement with the microsatellite results, giving us good support for the accurate assignment of parentage in our population.

  • 293.
    Barnaby, Jonathan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology.
    Fletcher, Kevin
    Ekman, Jan
    Group-living in the southern anteater-chat Myrmecocichla formicivora. Manuscript (preprint) (Other academic)
    Abstract [en]

    Group-living sets the scene for complex social behaviours such as cooperative breeding, and exploring the factors that shape group-living is crucial in understanding these behaviours. Here we describe some aspects of the ecology of a population of the facultative cooperative breeding southern anteater-chat (Myrmecocichla formicivora), a group living bird species endemic to southern Africa. We used data from a four year study of individually marked birds, with pedigrees completed using microsatellite genotyping. Southern anteater-chats live in groups of 2-5 individuals - a breeding pair and up to three additional none-breeders. These auxiliary birds were either retained offspring or unrelated individuals, and all birds in a group assisted by feeding at the nest. Our population had a skewed sex ratio of approximately 58% males to 42% females, yet the sex ratio of fledglings was equal, suggesting sex-biased mortality. Helpers were predominantly retained male offspring; however 21% of helpers were unrelated to either of the breeding pair. Southern anteater-chats appear to be non-territorial, with an apparent lack of aggression both within and between groups. Our study confirms that the southern anteater-chat is a facultative cooperative breeder, with both pair breeders and groups with helpers capable of fledging youngsters. We provide evidence suggesting that the breeding system of the southern anteater-chat is based on prompt female dispersal, and male philopatry due to an apparent shortage of mates, potential benefits of the natal site and possible high costs of floating. It appears that ecological constraints promoting delayed dispersal are reinforced by benefits gained from remaining philopatric.

  • 294.
    Barnaby, Jonathan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology.
    Griesser, Michael
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Population and Conservation Biology.
    The role of nepotism, cooperation, and competition in the avian families2010Book (Refereed)
    Abstract [en]

    A large number of bird species live in stable groups, and this sets the scene for complex social behaviours, such as cooperative breeding. The vast majority of groups consist of families which arise when young postpone dispersal and remain with their parents beyond independence. However, the factors selecting for the evolution of families and thus also cooperative breeding among birds, are still a challenging puzzle. The currently accepted key explanation for the evolution of families and cooperative breeding focuses on dispersal constraints. While constraints successfully explain within‐population dispersal decisions, they fail as an ultimate explanation because offspring in the majority of species face some sort of dispersal constraint, yet still disperse promptly. Recent alternative explanations focus on the role of philopatry and nepotism, and emphasise a key role of life‐history for the evolution of families. Phylogenetic analyses and field studies have indicated that living in family groups is far more widespread among long‐lived species than short‐lived ones. A long lifespan gives parents the opportunity to invest in their offspring for a prolonged period, while this option is less viable for short‐lived species. Thus, living with nepotistic parents provides offspring with direct fitness benefits that can select for the evolution of family living beyond independence. Nevertheless this generalisation is brought into question since many long‐lived bird species do not live in family groups. An alternative approach attempts to explain family living through the variation in territory quality. Here the incentive to remain with the parents is created by the availability of resources on the natal territory independent of parental nepotism. However, there is not only cooperation, conflicts are also common place in families. Living with independent, sexually mature offspring can lead to conflicts through a change in resource availability or the death of aparent. Therefore families can be expected to be dynamic societies where both parent and offspring decisions depend on each other, and family maintenance depends upon the current ecological conditions. Based on  this background, here we review recent studies that have investigated the processes that facilitate family formation, and which highlight both cooperation and conflict that arises from living in family groups. We examine the strengths of current models and explore ideas for a more coherent framework in which to understand prolonged family association in birds. We argue that two paths lead to family living, depending on the life-history. In medium-short lived species where the postponement of independent reproduction comes at a high cost, offspring can benefit from an association with their parents until the next breeding season. In longer-lived species, offspring actually benefit from postponing the onset of independent reproduction, making family living beyond the first year of life an adaptive strategy, and giving the option for cooperative breeding. These processes are illustrated by 5 species-specific case studies. We then finally suggest a number of key questions to developing a deeper understanding of the evolution of family living in birds.

  • 295.
    Barnaby, Jonathan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Population and Conservation Biology.
    Herrmann, Eric
    Ekman, Jan
    Sex specific survival in the southern anteater-chat Mymecocichla formicivora. Manuscript (preprint) (Other academic)
    Abstract [en]

    Survival is a key factor behind life-history variation both between and within species. It is also a major influence on sociality in species which delay dispersal and live in family groups. Knowledge of differential survival rates between males and females and juveniles and adults give insights into the costs and benefits of different behavioural and life-history strategies. Here we investigate patterns of survival in a population of the southern anteater-chat (Myrmecocichla formicivora), a facultative cooperatively breeding passerine of southern Africa. Using data from a 9-year mark-capture-recapture study, we examined juvenile and adult sex related variation in survival, and the role of environmental variables (rainfall, temperature) for survival patterns in the population. Annual adult survival probability (mean ± SE) was 0.71 ± 0.03 for males and 0.60 ± 0.04 for females. Juvenile survival was lower for each sex, with juvenile female survival (0.36 ± 0.04) being 35% lower than juvenile male survival (0.55 ± 0.04). Using these estimates we calculated the mean life span (MLS) in years for male southern anteater-chat to be 4.0 ± 0.7, considerably higher than for females at 2.0 ± 0.4. These figures closely matched the population-age structure of the study area, and could explain the high male biased sex skew of adult birds in this population. Higher annual mean temperature was associated with higher survival, whereas higher annual rainfall was associated with lower survival for both sex and age classes. Female survival, particularly female juvenile survival, may be reduced due to prompt dispersal and longer dispersal distances, and the additional costs of breeding early in life. Differential survival can promote male philopatry and this in turn could well encourage the cooperative breeding we see in the southern anteater-chat.

  • 296. Barnes, Ian
    et al.
    Duda, Anna
    Pybus, Oliver G.
    Thomas, Mark G.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Ancient urbanization predicts genetic resistance to tuberculosis2011In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 65, no 3, p. 842-848Article in journal (Refereed)
    Abstract [en]

    A link between urban living and disease is seen in recent and historical records, but the presence of this association in prehistory has been difficult to assess. If the transition to urban living does result in an increase in disease-based mortality, we might expect to see evidence of increased disease resistance in longer-term urbanized populations, as the result of natural selection. To test this, we determined the frequency of an allele (SLC11A1 1729 + 55del4) associated with natural resistance to intracellular pathogens such as tuberculosis and leprosy. We found a highly significantly correlation with duration of urban settlement-populations with a long history of living in towns are better adapted to resisting these infections. This correlation remains strong when we correct for autocorrelation in allele frequencies due to shared population history. Our results therefore support the interpretation that infectious disease loads became an increasingly important cause of human mortality after the advent of urbanization, highlighting the importance of population density in determining human health and the genetic structure of human populations.

  • 297. Barrett, S. C. H.
    et al.
    Ness, R. W.
    Vallejo-Marin, M.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Evolutionary pathways to self-fertilization in a tristylous plant species2009In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 183, no 3, p. 546-556Article in journal (Refereed)
    Abstract [en]

    P>Evolutionary transitions from outcrossing to selfing occur commonly in heterostylous genera. The morphological polymorphisms that characterize heterostyly provide opportunities for different pathways for selfing to evolve. Here, we investigate the origins and pathways by which selfing has evolved in tristylous Eichhornia paniculata by providing new evidence based on morphology, DNA sequences and genetic analysis. The primary pathway from outcrossing to selfing involves the stochastic loss of the short-styled morph (S-morph) from trimorphic populations, followed by the spread of selfing variants of the mid-styled morph (M-morph). However, the discovery of selfing variants of the long-styled morph (L-morph) in Central America indicates a secondary pathway and distinct origin for selfing. Comparisons of multi-locus nucleotide sequences from 27 populations sampled from throughout the geographical range suggest multiple transitions to selfing. Genetic analysis of selfing variants of the L- and M-morphs demonstrates recessive control of the loss of herkogamy, although the number of factors appears to differ between the forms. Early stages in the establishment of selfing involve developmental instability in the formation of flowers capable of autonomous self-pollination. The relatively simple genetic control of herkogamy reduction and frequent colonizing episodes may often create demographic conditions favouring transitions to selfing in E. paniculata. New Phytologist (2009) 183: 546-556doi: 10.1111/j.1469-8137.2009.02937.x.

  • 298. Barros, Nathan
    et al.
    Cole, Jonathan J.
    Tranvik, Lars J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Prairie, Yves T.
    Bastviken, David
    Huszar, Vera L. M.
    del Giorgio, Paul
    Roland, Fabio
    Carbon emission from hydroelectric reservoirs linked to reservoir age and latitude2011In: Nature Geoscience, ISSN 1752-0894, E-ISSN 1752-0908, Vol. 4, no 9, p. 593-596Article in journal (Refereed)
    Abstract [en]

    Hydroelectric reservoirs cover an area of 3.4 x 10(5) km(2) and comprise about 20% of all reservoirs. In addition, they contain large stores of formerly terrestrial organic carbon. Significant amounts of greenhouse gases are emitted(2), especially in the early years following reservoir creation, but the global extent of these emissions is poorly known. Previous estimates of emissions from all types of reservoir indicate that these human-made systems emit 321 Tg of carbon per year (ref. 4). Here we assess the emissions of carbon dioxide and methane from hydroelectric reservoirs, on the basis of data from 85 globally distributed hydroelectric reservoirs that account for 20% of the global area of these systems. We relate the emissions to reservoir age, location biome, morphometric features and chemical status. We estimate that hydroelectric reservoirs emit about 48 Tg C as CO(2) and 3 Tg C as CH(4), corresponding to 4% of global carbon emissions from inland waters. Our estimates are smaller than previous estimates on the basis of more limited data. Carbon emissions are correlated to reservoir age and latitude, with the highest emission rates from the tropical Amazon region. We conclude that future emissions will be highly dependent on the geographic location of new hydroelectric reservoirs.

  • 299.
    Barsh, Gregory S.
    et al.
    Stanford University.
    Anderson, Tovi M.
    Stanford University.
    Vonholdt, Bridgett M.
    University of California.
    Candille, Sophie I.
    Stanford University.
    Musiani, Marco
    University of Calgary.
    Stahler, Daniel R.
    University of California.
    Leonard, Jennifer
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Padhukasahasram, Badri
    Cornell University.
    Randi, Ettore
    Instituto Nazionale per la Fauna Selvatica.
    Bustamante, Carlos D.
    Cornell University.
    Ostrander, Elaine A.
    National Human Genome Research Institute, Bethesda.
    Tang, Hua
    Stanford University.
    Wayne, Robert K.
    University of California.
    How the Gray Wolf Got Its Color - Response2009In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 325, no 5936, p. 34-34Article in journal (Refereed)
  • 300.
    Bartels, Pia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Ecology across Boundaries: Food web coupling among and within ecosystems2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Cross-boundary movements of energy and material are ubiquitous. Freshwater ecosystems receive nutrients, dissolved, and particulate organic matter from adjacent terrestrial ecosystems, whereas terrestrial ecosystems mainly receive prey organisms and detritus deposited by physical processes such as floods from freshwater ecosystems. Within lakes, fish are considered as integrators between habitats due to their high mobility, although they often occupy either near-shore littoral or open-water pelagic habitats and develop habitat-specific morphologies. Such intra-population divergence in morphological traits might limit the use of multiple habitats.

    In this thesis, I first focused on quantity and quality of reciprocal fluxes of particulate organic matter between freshwater and terrestrial ecosystems and responses of recipient consumers. Freshwater ecosystems generally received higher amounts of externally-produced resources than terrestrial ecosystems. Despite this discrepancy, aquatic and terrestrial consumer responses were similar, likely due to the differences in resource quality. Second, I investigated the potential of particulate organic carbon (POC) supporting benthic food webs in lakes; a pathway that has largely been neglected in previous studies. I found that POC can substantially subsidize the benthic food web and that the effects on the benthic food web were transferred to the pelagic habitat, thus emphasizing the importance of benthic pathways for pelagic production. Third, I examined how water transparency can affect intra-population divergence in perch (Perca fluviatilis). I observed that increased water transparency can considerably increase morphological divergence between littoral and pelagic populations likely due to its effects on foraging. Finally, I investigated the effects of such intra-population divergence on littoral-pelagic food web coupling. I found that low morphological divergence corresponded with high overlap in resource use, whereas strong morphological divergence resulted in low overlap in resource use. Here littoral populations mainly utilized littoral resources and pelagic populations primarily utilized pelagic resources, indicating that habitat coupling might be strongly limited when intra-population divergence is high.

    In conclusion, although different ecosystems seem separated by distinct physical boundaries, these boundaries are often crossed. However, the development of habitat-specific adaptive traits might limit movement between apparently contiguous habitats.

    List of papers
    1. Reciprocal subsidies between freshwater and terrestrial ecosystems structure consumer-resource dynamics
    Open this publication in new window or tab >>Reciprocal subsidies between freshwater and terrestrial ecosystems structure consumer-resource dynamics
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    2012 (English)In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 93, no 5, p. 1173-1182Article in journal (Refereed) Published
    Abstract [en]

    Cross-ecosystem movements of material and energy, particularly reciprocal resource fluxes across the freshwater-land interface, have received major attention. Freshwater ecosystems may receive higher amounts of subsidies (i.e., resources produced outside the focal ecosystem) than terrestrial ecosystems, potentially leading to increased secondary production in freshwaters. Here we used a meta-analytic approach to quantify the magnitude and direction of subsidy inputs across the freshwater-land interface and to determine subsequent responses in recipient animals. Terrestrial and freshwater ecosystems differed in the magnitude of subsidies they received, with aquatic ecosystems generally receiving higher subsidies than terrestrial ecosystems. Surprisingly, and despite the large discrepancy in magnitude, the contribution of these subsidies to animal carbon inferred from stable isotope composition did not differ between freshwater and terrestrial ecosystems, likely due to the differences in subsidy quality. The contribution of allochthonous subsidies was highest to primary consumers and predators, suggesting that bottom-up and top-down effects may be affected considerably by the input of allochthonous resources. Future work on subsidies will profit from a food web dynamic approach including indirect trophic interactions and propagating effects.

    National Category
    Ecology
    Identifiers
    urn:nbn:se:uu:diva-160772 (URN)10.1890/11-1210.1 (DOI)000304368100022 ()
    Available from: 2011-10-31 Created: 2011-10-31 Last updated: 2017-12-08Bibliographically approved
    2. Terrestrial subsidies to lake food webs: An experimental approach
    Open this publication in new window or tab >>Terrestrial subsidies to lake food webs: An experimental approach
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    2012 (English)In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 168, no 3, p. 807-818Article in journal (Refereed) Published
    Abstract [en]

    Cross-ecosystem movements of material and energy are ubiquitous. Aquatic ecosystems typically receive material that also includes organic matter from the surrounding catchment. Terrestrial-derived (allochthonous) organic matter can enter aquatic ecosystems in dissolved or particulate form. Several studies have highlighted the importance of dissolved organic carbon to aquatic consumers, but less is known about allochthonous particulate organic carbon (POC). Similarly, most studies showing the effects of allochthonous organic carbon (OC) on aquatic consumers have investigated pelagic habitats; the effects of allochthonous OC on benthic communities are less well studied. Allochthonous inputs might further decrease primary production through light reduction, thereby potentially affecting autotrophic resource availability to consumers. Here, an enclosure experiment was carried out to test the importance of POC input and light availability on the resource use in a benthic food web of a clear-water lake. Corn starch (a C-4 plant) was used as a POC source due to its insoluble nature and its distinct carbon stable isotope value (delta C-13). The starch carbon was closely dispersed over the bottom of the enclosures to study the fate of a POC source exclusively available to sediment biota. The addition of starch carbon resulted in a clear shift in the isotopic signature of surface-dwelling herbivorous and predatory invertebrates. Although the starch carbon was added solely to the sediment surface, the carbon originating from the starch reached zooplankton. We suggest that allochthonous POC can subsidize benthic food webs directly and can be further transferred to pelagic systems, thereby highlighting the importance of benthic pathways for pelagic habitats.

    Keywords
    Allochthonous, Cross-ecosystem, Autochthonous, Aquatic-terrestrial linkage, Benthic
    National Category
    Ecology
    Identifiers
    urn:nbn:se:uu:diva-160774 (URN)10.1007/s00442-011-2141-7 (DOI)000301706800020 ()
    Available from: 2011-10-31 Created: 2011-10-31 Last updated: 2020-01-28Bibliographically approved
    3. Water transparency drives intra-population divergence in Eurasian perch (Perca fluviatilis)
    Open this publication in new window or tab >>Water transparency drives intra-population divergence in Eurasian perch (Perca fluviatilis)
    2012 (English)In: PLOS ONE, E-ISSN 1932-6203, Vol. 7, no 8, p. e43641-Article in journal (Refereed) Published
    Abstract [en]

    Trait combinations that lead to a higher efficiency in resource utilization are important drivers of divergent natural selection and adaptive radiation. However, variation in environmental features might constrain foraging in complex ways and therefore impede the exploitation of critical resources. We tested the effect of water transparency on intra-population divergence in morphology of Eurasian perch (Perca fluviatilis) across seven lakes in central Sweden. Morphological divergence between near-shore littoral and open-water pelagic perch substantially increased with increasing water transparency. Reliance on littoral resources increased strongly with increasing water transparency in littoral populations, whereas littoral reliance was not affected by water transparency in pelagic populations. Despite the similar reliance on pelagic resources in pelagic populations along the water transparency gradient, the utilization of particular pelagic prey items differed with variation in water transparency in pelagic populations. Pelagic perch utilized cladocerans in lakes with high water transparency and copepods in lakes with low water transparency. We suggest that under impaired visual conditions low utilization of littoral resources by littoral perch and utilization of evasive copepods by pelagic perch may lead to changes in morphology. Our findings indicate that visual conditions can affect population divergence in predator populations through their effects on resource utilization.

    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:uu:diva-158689 (URN)10.1371/journal.pone.0043641 (DOI)000308063700123 ()
    Available from: 2011-09-13 Created: 2011-09-13 Last updated: 2022-01-28Bibliographically approved
    4. Intra-population niche separation mediated by water transparency limits habitat coupling
    Open this publication in new window or tab >>Intra-population niche separation mediated by water transparency limits habitat coupling
    (English)Manuscript (preprint) (Other academic)
    National Category
    Ecology
    Identifiers
    urn:nbn:se:uu:diva-160776 (URN)
    Available from: 2011-10-31 Created: 2011-10-31 Last updated: 2013-02-11
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