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  • 51. Andres, J A
    et al.
    Arnqvist, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Genetic divergence of the seminal signal-receptor system in houseflies: the footprints of sexually antagonistic coevolution?2001In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 268, no 1465, p. 399-405Article in journal (Refereed)
  • 52. Antoniazza, Sylvain
    et al.
    Burri, Reto
    Fumagalli, Luca
    Goudet, Jérôme
    Roulin, Alexandre
    Local adaptation maintains clinal variation in melanin-based coloration of European barn owls (Tyto alba).2010In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 64, no 7, p. 1944-1954Article in journal (Refereed)
    Abstract [en]

    Ecological parameters vary in space, and the resulting heterogeneity of selective forces can drive adaptive population divergence. Clinal variation represents a classical model to study the interplay of gene flow and selection in the dynamics of this local adaptation process. Although geographic variation in phenotypic traits in discrete populations could be remainders of past adaptation, maintenance of adaptive clinal variation requires recurrent selection. Clinal variation in genetically determined traits is generally attributed to adaptation of different genotypes to local conditions along an environmental gradient, although it can as well arise from neutral processes. Here, we investigated whether selection accounts for the strong clinal variation observed in a highly heritable pheomelanin-based color trait in the European barn owl by comparing spatial differentiation of color and of neutral genes among populations. Barn owl's coloration varies continuously from white in southwestern Europe to reddish-brown in northeastern Europe. A very low differentiation at neutral genetic markers suggests that substantial gene flow occurs among populations. The persistence of pronounced color differentiation despite this strong gene flow is consistent with the hypothesis that selection is the primary force maintaining color variation among European populations. Therefore, the color cline is most likely the result of local adaptation.

  • 53. Aplin, Lucy M.
    et al.
    Farine, Damien R.
    Morand-Ferron, Julie
    Cockburn, Andrew
    Thornton, Alex
    Sheldon, Ben C.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics.
    Experimentally induced innovations lead to persistent culture via conformity in wild birds2015In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 518, no 7540, p. 538-541Article in journal (Refereed)
    Abstract [en]

    In human societies, cultural norms arise when behaviours are transmitted through social networks via high-fidelity social learning'. However, a paucity of experimental studies has meant that there is no comparable understanding of the process by which socially transmitted behaviours might spread and persist in animal populations'''. Here we show experimental evidence of the establishment of foraging traditions in a wild bird population. We introduced alternative novel foraging techniques into replicated wild sub-populations of great tits (Parus major) and used automated tracking to map the diffusion, establishment and long-term persistence of the seeded innovations. Furthermore, we used social network analysis to examine the social factors that influenced diffusion dynamics. From only two trained birds in each sub-population, the information spread rapidly through social network ties, to reach an average of 75% of individuals, with a total of 414 knowledgeable individuals performing 57,909 solutions over all replicates. The sub-populations were heavily biased towards using the technique that was originally introduced, resulting in established local traditions that were stable over two generations, despite a high population turnover. Finally, we demonstrate a strong effect of social conformity, with individuals disproportionately adopting the most frequent local variant when first acquiring an innovation, and continuing to favour social information over personal information. Cultural conformity is thought to be a key factor in the evolution of complex culture in humans''. In providing the first experimental demonstration of conformity in a wild non-primate, and of cultural norms in foraging techniques in any wild animal, our results suggest a much broader taxonomic occurrence of such an apparently complex cultural behaviour.

  • 54.
    Appelgren, Anais S. C.
    et al.
    Univ Bern, Inst Ecol & Evolut, Evolutionary Ecol Lab, Baltzerstr 6, Bern, Switzerland;Univ Lyon, CNRS, F-69000 Lyon, France;LBBE UMR 5558, Dept Biometry & Evolutionary Biol, Batiment Gregor Mendel,43 Blvd 11 Novembre 1918, F-69622 Villeurbanne, France;Univ Lyon 1, Dept Biometry & Evolutionary Biol, LBBE UMR 5558, Batiment Gregor Mendel,43 Blvd 11 Novembre 1918, F-69622 Villeurbanne, France;Univ Montpellier, Ctr IRD, Agropolis, MIVEGEC,CNRS,IRD, 911 Ave,BP 64501, F-34000 Montpellier, France.
    Saladin, Verena
    Univ Bern, Inst Ecol & Evolut, Evolutionary Ecol Lab, Baltzerstr 6, Bern, Switzerland.
    Richner, Heinz
    Univ Bern, Inst Ecol & Evolut, Evolutionary Ecol Lab, Baltzerstr 6, Bern, Switzerland.
    Doligez, Blandine
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ Lyon, CNRS, F-69000 Lyon, France;LBBE UMR 5558, Dept Biometry & Evolutionary Biol, Batiment Gregor Mendel,43 Blvd 11 Novembre 1918, F-69622 Villeurbanne, France;Univ Lyon 1, Dept Biometry & Evolutionary Biol, LBBE UMR 5558, Batiment Gregor Mendel,43 Blvd 11 Novembre 1918, F-69622 Villeurbanne, France.
    McCoy, Karen D.
    Univ Montpellier, Ctr IRD, Agropolis, MIVEGEC,CNRS,IRD, 911 Ave,BP 64501, F-34000 Montpellier, France.
    Gene flow and adaptive potential in a generalist ectoparasite2018In: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 18, article id 99Article in journal (Refereed)
    Abstract [en]

    Background: In host-parasite systems, relative dispersal rates condition genetic novelty within populations and thus their adaptive potential. Knowledge of host and parasite dispersal rates can therefore help us to understand current interaction patterns in wild populations and why these patterns shift over time and space. For generalist parasites however, estimates of dispersal rates depend on both host range and the considered spatial scale. Here, we assess the relative contribution of these factors by studying the population genetic structure of a common avian ectoparasite, the hen flea Ceratophyllus gallinae, exploiting two hosts that are sympatric in our study population, the great tit Paws major and the collared flycatcher Ficedula albicollis. Previous experimental studies have indicated that the hen flea is both locally maladapted to great tit populations and composed of subpopulations specialized on the two host species, suggesting limited parasite dispersal in space and among hosts, and a potential interaction between these two structuring factors. Results: C gallinae fleas were sampled from old nests of the two passerine species in three replicate wood patches and were genotyped at microsatellite markers to assess population genetic structure at different scales (among individuals within a nest among nests and between host species within a patch and among patches). As expected, significant structure was found at all spatial scales and between host species, supporting the hypothesis of limited dispersal in this parasite. Clustering analyses and estimates of relatedness further suggested that inbreeding regularly occurs within nests. Patterns of isolation by distance within wood patches indicated that flea dispersal likely occurs in a stepwise manner among neighboring nests. From these data, we estimated that gene flow in the hen flea is approximately half that previously described for its great tit hosts. Conclusion: Our results fall in line with predictions based on observed patterns of adaptation in this host-parasite system, suggesting that parasite dispersal is limited and impacts its adaptive potential with respect to its hosts. More generally, this study sheds light on the complex interaction between parasite gene flow, local adaptation and host specialization within a single host-parasite system.

  • 55.
    Arbuthnott, Devin
    et al.
    Univ British Columbia, Dept Zool, 4200-6270 Univ Blvd, Vancouver, BC V6T 1Z4, Canada.;Univ British Columbia, Biodivers Res Ctr, 4200-6270 Univ Blvd, Vancouver, BC V6T 1Z4, Canada..
    Mautz, Brian S.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Rundle, Howard D.
    Univ Ottawa, Dept Biol, Ottawa, ON, Canada..
    Rugged fitness landscapes and by-product adaptation in experimental populations of Drosophila melanogaster2018In: Evolutionary Ecology Research, ISSN 1522-0613, E-ISSN 1937-3791, Vol. 19, no 1, p. 15-28Article in journal (Refereed)
    Abstract [en]

    Background: While the concept of the fitness landscape is central to evolutionary theory, empirical characterizations of fitness landscapes have remained difficult. Recently, a number of laboratory experiments using microbes have suggested that fitness landscapes are often rugged, though there is some variation across environments and species. However, there have been very few characterizations of fitness landscapes in sexual organisms, making it unclear whether the conclusions from studies of microbes are applicable to other groups. Questions: Are fitness landscapes smooth or rugged in simplified laboratory environments for sexual organisms? How does landscape topography influence patterns of adaptation? Methods: We conducted a series of experiments using replicate populations of Drosophila melanogaster adapted to either cadmium-or ethanol-enriched food to characterize the fitness and phenotypes of these populations in a simplified laboratory environment (ethanol-enriched media). Results: We found that replicate populations adapted to different laboratory environments have diverged phenotypically in physiology, mating behaviour, and offspring production in alternate environments. However, both ethanol-and cadmium-adapted populations show high fitness in the ethanol-enriched environment relative to their founding population, and cadmium-adapted males actually outcompete ethanol-adapted males for mates in an ethanol environment. Conclusions: Our data indicate that the simplified ethanol-enriched medium represents a rugged fitness landscape, and that alternately adapted populations occupy different fitness peaks on this landscape. Because cadmium-adapted populations were never exposed to ethanol previously, it appears that these populations adapted to ethanol as a by-product of adaptation to their cadmium-enriched environment. Therefore, even in simplified laboratory environments, we find evidence for rugged fitness landscapes, and the overlap of fitness peaks on the phenotypic landscape allowed for by-product adaptation.

  • 56.
    Arct, Aneta
    et al.
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Sudyka, Joanna
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Podmoka, Edyta
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Drobniak, Szymon M.
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Cichon, Mariusz
    Jagiellonian Univ, Inst Environm Sci, Gronostajowa 7, PL-30387 Krakow, Poland..
    Heterozygosity-fitness correlations in blue tit nestlings (Cyanistis caeruleus) under contrasting rearing conditions2017In: Evolutionary Ecology, ISSN 0269-7653, E-ISSN 1573-8477, Vol. 31, no 5, p. 803-814Article in journal (Refereed)
    Abstract [en]

    Understanding the relation between genetic variation and fitness remains a key question in evolutionary biology. Although heterozygosity has been reported to correlate with many fitness-related traits, the strength of the heterozygosity-fitness correlations (HFCs) is usually weak and it is still difficult to assess the generality of these associations in natural populations. It has been suggested that HFCs may become meaningful only under particular environmental conditions. Moreover, existing evidence suggests that HFCs may also differ between sexes. The aim of this study was to investigate correlations between heterozygosity in neutral markers (microsatellites) and fitness-related traits in a natural population of blue tits (Cyanistes caeruleus). Additionally, we tested whether sex and environmental conditions may influence the magnitude and direction of HFCs. We found a positive relationship between heterozygosity and body mass of 14 days post-hatching nestlings, but only among females. Our results suggest that the correlation between heterozygosity and nestling body mass observed among female offspring could be attributed to within-brood effects. We failed to find any evidence that environmental conditions as simulated by brood size manipulation affect HFCs.

  • 57. Arnegard, Matthew E.
    et al.
    McGee, Matthew D.
    Matthews, Blake
    Marchinko, Kerry B.
    Conte, Gina L.
    Kabir, Sahriar
    Bedford, Nicole
    Bergek, Sara
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Chan, Yingguang Frank
    Jones, Felicity C.
    Kingsley, David M.
    Peichel, Catherine L.
    Schluter, Dolph
    Genetics of ecological divergence during speciation2014In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 511, no 7509, p. 307-311Article in journal (Refereed)
    Abstract [en]

    Ecological differences often evolve early in speciation as divergent natural selection drives adaptation to distinct ecological niches, leading ultimately to reproductive isolation. Although this process is a major generator of biodiversity, its genetic basis is still poorly understood. Here we investigate the genetic architecture of niche differentiation in a sympatric species pair of threespine stickleback fish by mapping the environment-dependent effects of phenotypic traits on hybrid feeding and performance under semi-natural conditions. We show that multiple, unlinked loci act largely additively to determine position along the major niche axis separating these recently diverged species. We also find that functional mismatch between phenotypic traits reduces the growth of some stickleback hybrids beyond that expected from an intermediate phenotype, suggesting a role for epistasis between the underlying genes. This functional mismatch might lead to hybrid incompatibilities that are analogous to those underlying intrinsic reproductive isolation but depend on the ecological context.

  • 58.
    Arnqvist, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Comparative evidence for the evolution of genitalia by sexual selection1998In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 393, no 6687, p. 784-786Article in journal (Refereed)
  • 59.
    Arnqvist, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Cryptic female choice2014In: The Evolution of Insect Mating Systems / [ed] D. Shuker and L. Simmons, Oxford: Oxford University Press, 2014, p. 204-220Chapter in book (Other academic)
  • 60.
    Arnqvist, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    MULTIPLE MATING IN A WATER STRIDER - MUTUAL BENEFITS OR INTERSEXUAL CONFLICT1989In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 38, p. 749-756Article in journal (Refereed)
  • 61.
    Arnqvist, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sensory exploitation and sexual conflict2006In: Philosophical Transactions of the Royal Society of London. Biological Sciences, ISSN 0962-8436, E-ISSN 1471-2970, Vol. 361, no 1466, p. 375-386Article in journal (Refereed)
  • 62.
    Arnqvist, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sex wars: Genes, bacteria, and biased sex ratios2003In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 424, no 6949, p. 616-617Article in journal (Refereed)
  • 63.
    Arnqvist, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sexual conflict and sexual selection: Lost in the chase2004In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 58, no 6, p. 1383-1388Article in journal (Refereed)
  • 64.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Andres, Jose A.
    The effects of experimentally induced polyandry on female reproduction in a monandrous mating system2006In: Ethology, ISSN 0179-1613, E-ISSN 1439-0310, Vol. 112, no 8, p. 748-756Article in journal (Refereed)
  • 65.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Danielsson, I
    Copulatory behavior, genital morphology, and male fertilization success in water striders1999In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 53, no 1, p. 147-156Article in journal (Refereed)
  • 66.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Danielsson, I
    Postmating sexual selection: the effects of male body size and recovery period on paternity and egg production rate in a water strider1999In: Behavioral Ecology, ISSN 1045-2249, E-ISSN 1465-7279, Vol. 10, no 4, p. 358-365Article in journal (Refereed)
  • 67.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Edvardsson, M
    Friberg, U
    Nilsson, T
    Sexual conflict promotes speciation in insects2000In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 97, no 19, p. 10460-10464Article in journal (Refereed)
  • 68.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Fricke, C
    Arnqvist, G
    Patterns of divergence in the effects of mating on female reproductive performance in flour beetles2002In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 56, no 1, p. 111-120Article in journal (Refereed)
  • 69.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Johansson, F
    Ontogenetic reaction norms of predator-induced defensive morphology in dragonfly larvae1998In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 79, no 6, p. 1847-1858Article in journal (Refereed)
  • 70.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Jones, T M
    Elgar, M A
    Insect behaviour: Reversal of sex roles in nuptial feeding2003In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 424, no 6947, p. 387-387Article in journal (Refereed)
  • 71.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Kirkpatrick, M
    The evolution of infidelity in socially monogamous passerines: The strength of direct and indirect selection on extrapair copulation behavior in females2005In: American Naturalist, ISSN 0003-0147, E-ISSN 1537-5323, Vol. 165, no 5, p. S26-S37Article in journal (Refereed)
  • 72.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Martensson, T
    Measurement error in geometric morphometrics: Empirical strategies to assess and reduce its impact on measures of shape1998In: Acta Zoologica Academiae Scientiarum Hungaricae, ISSN 1217-8837, E-ISSN 2064-2474, Vol. 44, no 1-2, p. 73-96Article in journal (Refereed)
  • 73.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Nilsson, T
    The evolution of polyandry: multiple mating and female fitness in insects2000In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 60, p. 145-164Article, review/survey (Refereed)
  • 74.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Nilsson, T
    Katvala, M
    Mating rate and fitness in female bean weevils2005In: Behavioral Ecology, ISSN 1045-2249, E-ISSN 1465-7279, Vol. 16, no 1, p. 123-127Article in journal (Refereed)
  • 75.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Rowe, L
    Antagonistic coevolution between the sexes in a group of insects2002In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 415, no 6873, p. 787-789Article in journal (Refereed)
  • 76.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Rowe, L
    Correlated evolution of male and female morphologies in water striders2002In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 56, no 5, p. 936-947Article in journal (Refereed)
  • 77.
    Arnqvist, Göran
    et al.
    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.
    Immonen, Elina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Hotzy, Cosima
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Rankin, Daniel
    Univ Zurich, Inst Evolutionary Biol & Environm Studies, Zurich, Switzerland..
    Tuda, Midori
    Kyushu Univ, Dept Bioresource Sci, Lab Insect Nat Enemies, Fukuoka 8128581, Japan.;Kyushu Univ, Inst Biol Control, Fac Agr, Fukuoka 8128581, Japan..
    Hjelmen, Carl E.
    Texas A&M Univ, Dept Entomol, College Stn, TX 77843 USA..
    Johnston, J. Spencer
    Texas A&M Univ, Dept Entomol, College Stn, TX 77843 USA..
    Genome size correlates with reproductive fitness in seed beetles2015In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 282, no 1815, article id 20151421Article in journal (Refereed)
    Abstract [en]

    The ultimate cause of genome size (GS) evolution in eukaryotes remains a major and unresolved puzzle in evolutionary biology. Large-scale comparative studies have failed to find consistent correlations between GS and organismal properties, resulting in the 'C-value paradox'. Current hypotheses for the evolution of GS are based either on the balance between mutational events and drift or on natural selection acting upon standing genetic variation in GS. It is, however, currently very difficult to evaluate the role of selection because within-species studies that relate variation in life-history traits to variation in GS are very rare. Here, we report phylogenetic comparative analyses of GS evolution in seed beetles at two distinct taxonomic scales, which combines replicated estimation of GS with experimental assays of life-history traits and reproductive fitness. GS showed rapid and bidirectional evolution across species, but did not show correlated evolution with any of several indices of the relative importance of genetic drift. Within a single species, GS varied by 4-5% across populations and showed positive correlated evolution with independent estimates of male and female reproductive fitness. Collectively, the phylogenetic pattern of GS diversification across and within species in conjunction with the pattern of correlated evolution between GS and fitness provide novel support for the tenet that natural selection plays a key role in shaping GS evolution.

  • 78.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Stojkovic, Biljana
    Department of Evolutionary Biology, Institute for Biological Research, University of Belgrade, Belgrade, Serbia.; Institute of Zoology, Faculty of Biology, University of Belgrade, Belgrade, Serbia.
    Rönn, Johanna L.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Immonen, Elina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    The pace-of-life: A sex-specific link between metabolic rate and life history in bean beetles2017In: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 31, no 12, p. 2299-2309Article in journal (Refereed)
    Abstract [en]
    1. Metabolic rate (MR) is a key functional trait simply because metabolism converts resources into population growth rate. Yet, our empirical understanding of the sources of within species variation in MR, as well as of its life history and ecological correlates, is rather limited. Here, we assess whether MR lies at the root of a syndrome of correlated rate-dependent life-history traits in an insect.
    2. Selection for early (E) or late (L) age-at-reproduction for >160 generations in the bean beetle Acanthoscelides obtectus has produced beetles that differ markedly in juvenile development, body size, fecundity schedules, ageing and life span. Here, we use micro-respirometry to test whether this has been associated with the evolution of age- and sex-specific metabolic phenotypes.
    3. We find that mass-specific MR is 18% higher in E lines compared to L lines and that MR decreases more rapidly with chronological, but not biological, age in E lines. Males, under sexual selection to “live-fast-die-young”, show 50% higher MR than females and MR decreased more rapidly with age in males.
    4. Our results are consistent with a central role for MR for the divergence in “pace-of-life” seen in these beetles, supporting the view that MR lies at the root of ecologically relevant life-history trait variation within species.
  • 79.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Stojković, Biljana
    Rönn, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Immonen, Elina
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    The pace-of-life: A sex-specific link between metabolic rate and life history in bean beetles2017In: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 31, no 12, p. 2299-2309Article in journal (Refereed)
    Abstract [en]

    1. Metabolic rate (MR) is a key functional trait simply because metabolism converts resources into population growth rate. Yet, our empirical understanding of the sources of within species variation in MR, as well as of its life history and ecological correlates, is rather limited. Here, we assess whether MR lies at the root of a syndrome of correlated rate‐dependent life‐history traits in an insect.
    2. Selection for early (E) or late (L) age‐at‐reproduction for >160 generations in the bean beetle Acanthoscelides obtectus has produced beetles that differ markedly in juvenile development, body size, fecundity schedules, ageing and life span. Here, we use micro‐respirometry to test whether this has been associated with the evolution of age‐ and sex‐specific metabolic phenotypes.
    3. We find that mass‐specific MR is 18% higher in E lines compared to L lines and that MR decreases more rapidly with chronological, but not biological, age in E lines. Males, under sexual selection to “live‐fast‐die‐young”, show 50% higher MR than females and MR decreased more rapidly with age in males.
    4. Our results are consistent with a central role for MR for the divergence in “pace‐of‐life” seen in these beetles, supporting the view that MR lies at the root of ecologically relevant life‐history trait variation within species.
  • 80.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Thornhill, R
    Evolution of animal genitalia: patterns of phenotypic and genotypic variation and condition dependence of genital and non-genital morphology in water strider (Heteroptera : Gerridae : Insecta)1998In: Genetical Research, ISSN 0016-6723, E-ISSN 1469-5073, Vol. 71, no 3, p. 193-212Article in journal (Refereed)
  • 81.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Vellnow, Nikolas
    Rowe, Locke
    The effect of epistasis on sexually antagonistic genetic variation2014In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 281, no 1787, p. 20140489-Article in journal (Refereed)
    Abstract [en]

    There is increasing evidence of segregating sexually antagonistic (SA) genetic variation for fitness in laboratory and wild populations, yet the conditions for the maintenance of such variation can be restrictive. Epistatic interactions between genes can contribute to the maintenance of genetic variance in fitness and we suggest that epistasis between SA genes should be pervasive. Here, we explore its effect on SA genetic variation in fitness using a two locus model with negative epistasis. Our results demonstrate that epistasis often increases the parameter space showing polymorphism for SA loci. This is because selection in one locus is affected by allele frequencies at the other, which can act to balance net selection in males and females. Increased linkage between SA loci had more marginal effects. We also show that under some conditions, large portions of the parameter space evolve to a state where male benefit alleles are fixed at one locus and female benefit alleles at the other. This novel effect of epistasis on SA loci, which we term the 'equity effect', may have important effects on population differentiation and may contribute to speciation. More generally, these results support the suggestion that epistasis contributes to population divergence.

  • 82.
    Ast, Jennifer C
    University of Michigan, Museum of Zoology and Department of Ecology and Evolutionary Biology.
    Mitochondrial DNA evidence and evolution in Varanoidea (Squamata)2001In: Cladistics, ISSN 0748-3007, E-ISSN 1096-0031, Vol. 17, no 3, p. 211-226Article in journal (Refereed)
    Abstract [en]

    Varanoidea is a monophyletic group of anguimorph lizards, comprising the New World helodermatids, the Bornean earless monitor Lanthanotus borneensis, and the Old World monitors (Varanus). I use mitochondrial DNA sequences and extensive taxonomic sampling to test alternative hypotheses of varanoid relationships. The most parsimonious hypothesis confirms the monophyly of Varanoidea (Heloderma, Lanthanotus, and Varanus) and Varanus, as well as the sister-taxon relationship of Varanus and Lanthanotus. The relationships among Varanus species differ in several respects from previous hypotheses. Three major lineages are recognized within Varanus: an African clade basal to the rest of the group, an Indo-Asian clade, and an Indo-Australian clade. Within the last lineage, the endemic Australian dwarf monitors (Odatria) form a clade sister to the large Australian monitors (the gouldii group). Tests of the effects of rate heterogeneity and homoplasy demonstrate that putative process partitions of data are largely congruent with one another and contribute positive support to the overall hypothesis.

  • 83.
    Augusto, Rafael
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Assortative reproduction in a seed beetle?2016Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    How genetic variation for fitness is maintained is still debated in evolutionary biology. Sexually antagonistic (SA) selection, favouring alternative alleles in males and females, has been proposed to be one mechanism capable of maintaining genetic variation for fitness. However the conditions under which SA polymorphisms are maintained are still thought to be somewhat restrictive. Several models have explored potential mechanisms that may help maintain genetic variation at SA loci. One such mechanism is assortative mating by fitness, where individuals with similar fitness mate more frequently than expected by random chance. This study explores if there is such assortative reproduction for fitness in a population of Callosobruchus maculatus seed beetles, which could explain the large amounts of SA genetic variance for fitness exhibited by this population. However, on the contrary, results show that there is evidence of disassortative reproduction for fitness in this population. 

  • 84. Axelsson, Erik
    Male-biased mutation rate and divergence in autosomal, z-linked and w-linked introns of chicken and Turkey2004In: Mol Biol Evol.Article in journal (Refereed)
  • 85.
    Axelsson, Erik
    et al.
    Department of Biology, Evolutionary Biology, Copenhagen University.
    Albrechtsen, A
    Department of Biostatistics, University of Copenhagen.
    van, A P
    Animal Breeding and Genomics Centre, Wageningen UR.
    Li, Lili
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Megens, H J
    Animal Breeding and Genomics Centre, Wageningen UR.
    Vereijken, A L J
    Hendrix Genetics BV, Boxmeer.
    Crooijmans, R P M A
    Animal Breeding and Genomics Centre, Wageningen UR.
    Groenen, M A M
    Animal Breeding and Genomics Centre, Wageningen UR.
    Ellegren, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Willerslev, E
    Department of Biology, Evolutionary Biology, Copenhagen University.
    Nielsen, R
    Department of Integrative Biology, University of California, Berkeley.
    Segregation distortion in chicken and the evolutionary consequences of female meiotic drive in birds2010In: Heredity, ISSN 0018-067X, E-ISSN 1365-2540, Vol. 105, no 3, p. 290-298Article in journal (Refereed)
    Abstract [en]

    As all four meiotic products give rise to sperm in males, female meiosis result in a single egg in most eukaryotes. Any genetic element with the potential to influence chromosome segregation, so that it is preferentially included in the egg, should therefore gain a transmission advantage; a process termed female meiotic drive. We are aware of two chromosomal components, centromeres and telomeres, which share the potential to influence chromosome movement during meioses and make the following predictions based on the presence of female meiotic drive: (1) centromere-binding proteins should experience rapid evolution as a result of a conflict between driving centromeres and the rest of the genome; and (2) segregation patterns should be skewed near centromeres and telomeres. To test these predictions, we first analyze the molecular evolution of seven centromere-binding proteins in nine divergent bird species. We find strong evidence for positive selection in two genes, lending support to the genomic conflict hypothesis. Then, to directly test for the presence of segregation distortion, we also investigate the transmission of ~9000 single-nucleotide polymorphisms in 197 chicken families. By simulating fair Mendelian meioses, we locate chromosomal regions with statistically significant transmission ratio distortion. One region is located near the centromere on chromosome 1 and a second region is located near the telomere on the p-arm of chromosome 1. Although these observations do not provide conclusive evidence in favour of the meiotic drive/genome conflict hypothesis, they do lend support to the hypothesis that centromeres and telomeres drive during female meioses in chicken.

  • 86. Axelsson, Erik
    et al.
    Webster, Matthew
    Base Composition Patterns2011In: Encyclopedia of Life Sciences, ISSN 1561592617 9781561592616Article, book review (Refereed)
  • 87. Axelsson, Erik
    et al.
    Willerslev, Eske
    Gilbert, M Thomas P
    Nielsen, Rasmus
    The effect of ancient DNA damage on inferences of demographic histories.2008In: Molecular biology and evolution, ISSN 0737-4038, E-ISSN 1537-1719, Vol. 25, no 10, p. 2181-7Article in journal (Refereed)
    Abstract [en]

    The field of ancient DNA (aDNA) is casting new light on many evolutionary questions. However, problems associated with the postmortem instability of DNA may complicate the interpretation of aDNA data. For example, in population genetic studies, the inclusion of damaged DNA may inflate estimates of diversity. In this paper, we examine the effect of DNA damage on population genetic estimates of ancestral population size. We simulate data using standard coalescent simulations that include postmortem damage and show that estimates of effective population sizes are inflated around, or right after, the sampling time of the ancestral DNA sequences. This bias leads to estimates of increasing, and then decreasing, population sizes, as observed in several recently published studies. We reanalyze a recently published data set of DNA sequences from the Bison (Bison bison/Bison priscus) and show that the signal for a change in effective population size in this data set vanishes once the effects of putative damage are removed. Our results suggest that population genetic analyses of aDNA sequences, which do not accurately account for damage, should be interpreted with great caution.

  • 88.
    Babiker, Hiba
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Schlebusch, Carina M
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Hassan, Hisham Y
    Jakobsson, Mattias
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Genetic variation and population structure of Sudanese populations as indicated by 15 Identifiler sequence-tagged repeat (STR) loci.2011In: Investigative Genetics, ISSN 2041-2223, E-ISSN 2041-2223, Vol. 2, no 1Article in journal (Refereed)
    Abstract [en]

    BACKGROUND: There is substantial ethnic, cultural and linguistic diversity among the people living in east Africa, Sudan and the Nile Valley. The region around the Nile Valley has a long history of succession of different groups, coupled with demographic and migration events, potentially leading to genetic structure among humans in the region.

    RESULT: We report the genotypes of the 15 Identifiler microsatellite markers for 498 individuals from 18 Sudanese populations representing different ethnic and linguistic groups. The combined power of exclusion (PE) was 0.9999981, and the combined match probability was 1 in 7.4 × 1017. The genotype data from the Sudanese populations was combined with previously published genotype data from Egypt, Somalia and the Karamoja population from Uganda. The Somali population was found to be genetically distinct from the other northeast African populations. Individuals from northern Sudan clustered together with those from Egypt, and individuals from southern Sudan clustered with those from the Karamoja population. The similarity of the Nubian and Egyptian populations suggest that migration, potentially bidirectional, occurred along the Nile river Valley, which is consistent with the historical evidence for long-term interactions between Egypt and Nubia.

    CONCLUSION: We show that despite the levels of population structure in Sudan, standard forensic summary statistics are robust tools for personal identification and parentage analysis in Sudan. Although some patterns of population structure can be revealed with 15 microsatellites, a much larger set of genetic markers is needed to detect fine-scale population structure in east Africa and the Nile Valley.

  • 89.
    Backström, Niclas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Adaptive evolution in passerine birds2014In: Encyclopedia of Life Sciences, ISSN 1476-9506, E-ISSN 1476-9506Article in journal (Other academic)
    Abstract [en]

    Adaptive evolution is the process whereby mutations that provide the carrier with a selective advantage increase in frequency in a population via the process of natural selection. Passerines are widespread, common and long-term targets for field study and they demonstrate a copious diversity in physiological and morphological adaptations to varying habitats, for example, beak size and wing shape, and they are, therefore, an important study system to understand adaptive evolution. Recent technological advancements have made it easier to investigate the mechanistic and evolutionary underpinnings of adaptive evolution by allowing genome sequence data to be generated in almost any species of interest. However, it is important to assess the contribution of neutral forces like demographic events and GC-biased gene conversion before concluding that selection has shaped the patterns observed in genomic data. Initial analyses in passerines have identified candidate genes that might be involved in, for example, song learning, beak morphology, disease resistance, high-altitude adaptation and exploratory behavior, but functional verifications are needed to establish a causative relationship between the identified genes and the traits. Key Concepts:Key Concepts: * Passerines are widespread, generally common and easy targets for field study and they demonstrate a copious diversity in physiological and morphological adaptations to varying habitats and they have, therefore, played an important role in previous studies concerning behaviour, ecology and evolution. * A full understanding of passerine adaptations requires an integrative approach aiming at identifying and characterising both proximate (mechanistic) and ultimate (evolutionary) underpinnings to adaptive traits. * The recent advancements in molecular techniques allows for using both comparative genomics, expression profiling, candidate gene approaches and classical association and QTL mapping strategies to identify the genetic basis of adaptive traits in passerines. * Groundwork studies of ecological genetics and genomics using comparative approaches, expression profiling and candidate genes are now accumulating and in a handful of cases we have an idea about the genetic basis of adaptive traits related to, for example, dietary specialisation, learning, exploratory behaviour, immune response and high-altitude adaptations in passerines. * Demographic history and other neutral processes, for example, GC-biased gene conversion (gcBGC), may mimic signals of selection and it is important to verify findings of adaptive evolution using independent methods.

  • 90.
    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, ISSN 1471-2148, 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.

  • 91.
    Bahram, Mohammad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology. Univ Tartu, Inst Ecol & Earth Sci, Dept Bot, 40 Lai St, Tartu, Estonia;Swedish Univ Agr Sci, Dept Ecol, Ulls Vag 16, S-75651 Uppsala, Sweden.
    Anslan, Sten
    Univ Tartu, Inst Ecol & Earth Sci, Dept Bot, 40 Lai St, Tartu, Estonia;Braunschweig Univ Technol, Zool Inst, Mendelssohnstr 4, D-38106 Braunschweig, Germany.
    Hildebrand, Falk
    European Mol Biol Lab, Struct & Computat Biol, Heidelberg, Germany.
    Bork, Peer
    European Mol Biol Lab, Struct & Computat Biol, Heidelberg, Germany;Max Delbruck Ctr Mol Med, Berlin, Germany;Univ Wurzburg, Bioctr, Dept Bioinformat, Wurzburg, Germany.
    Tedersoo, Leho
    Univ Tartu, Nat Hist Museum, 14A Ravila, EE-50411 Tartu, Estonia.
    Newly designed 16S rRNA metabarcoding primers amplify diverse and novel archaeal taxa from the environment2019In: Environmental Microbiology Reports, ISSN 1758-2229, E-ISSN 1758-2229, Vol. 11, no 4, p. 487-494Article in journal (Refereed)
    Abstract [en]

    High-throughput studies of microbial communities suggest that Archaea are a widespread component of microbial diversity in various ecosystems. However, proper quantification of archaeal diversity and community ecology remains limited, as sequence coverage of Archaea is usually low owing to the inability of available prokaryotic primers to efficiently amplify archaeal compared to bacterial rRNA genes. To improve identification and quantification of Archaea, we designed and validated the utility of several primer pairs to efficiently amplify archaeal 16S rRNA genes based on up-to-date reference genes. We demonstrate that several of these primer pairs amplify phylogenetically diverse Archaea with high sequencing coverage, outperforming commonly used primers. Based on comparing the resulting long 16S rRNA gene fragments with public databases from all habitats, we found several novel family- to phylum-level archaeal taxa from topsoil and surface water. Our results suggest that archaeal diversity has been largely overlooked due to the limitations of available primers, and that improved primer pairs enable to estimate archaeal diversity more accurately.

  • 92.
    Bahram, Mohammad
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Hildebrand, Falk
    Forslund, Sofia K
    Anderson, Jennifer L
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Soudzilovskaia, Nadejda A
    Bodegom, Peter M
    Bengtsson-Palme, Johan
    Anslan, Sten
    Coelho, Luis Pedro
    Harend, Helery
    Huerta-Cepas, Jaime
    Medema, Marnix H
    Maltz, Mia R
    Mundra, Sunil
    Olsson, Pål Axel
    Pent, Mari
    Põlme, Sergei
    Sunagawa, Shinichi
    Ryberg, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Tedersoo, Leho
    Bork, Peer
    Structure and function of the global topsoil microbiome.2018In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 560, no 7717, p. 233-237Article in journal (Refereed)
    Abstract [en]

    Soils harbour some of the most diverse microbiomes on Earth and are essential for both nutrient cycling and carbon storage. To understand soil functioning, it is necessary to model the global distribution patterns and functional gene repertoires of soil microorganisms, as well as the biotic and environmental associations between the diversity and structure of both bacterial and fungal soil communities1-4. Here we show, by leveraging metagenomics and metabarcoding of global topsoil samples (189 sites, 7,560 subsamples), that bacterial, but not fungal, genetic diversity is highest in temperate habitats and that microbial gene composition varies more strongly with environmental variables than with geographic distance. We demonstrate that fungi and bacteria show global niche differentiation that is associated with contrasting diversity responses to precipitation and soil pH. Furthermore, we provide evidence for strong bacterial-fungal antagonism, inferred from antibiotic-resistance genes, in topsoil and ocean habitats, indicating the substantial role of biotic interactions in shaping microbial communities. Our results suggest that both competition and environmental filtering affect the abundance, composition and encoded gene functions of bacterial and fungal communities, indicating that the relative contributions of these microorganisms to global nutrient cycling varies spatially.

  • 93.
    Baiao, Guilherme Costa
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Molecular Evolution.
    Schneider, Daniela I.
    Med Univ Vienna, Ctr Anat & Cell Biol, Lab Genome Dynam, Deparment Cell & Dev Biol, Schwarzspanierstr 17, A-1090 Vienna, Austria;Yale Univ, Dept Epidemiol Microbial Dis, 60 Coll St, New Haven, CT 06510 USA.
    Miller, Wolfgang J.
    Med Univ Vienna, Ctr Anat & Cell Biol, Lab Genome Dynam, Deparment Cell & Dev Biol, Schwarzspanierstr 17, A-1090 Vienna, Austria.
    Klasson, Lisa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Molecular Evolution.
    The effect of Wolbachia on gene expression in Drosophila paulistorum and its implications for symbiont-induced host speciation2019In: BMC Genomics, ISSN 1471-2164, E-ISSN 1471-2164, Vol. 20, article id 465Article in journal (Refereed)
    Abstract [en]

    Background: The Neotropical fruit fly Drosophila paulistorum (Diptera: Drosophilidae) is a species complex in statu nascendi comprising six reproductively isolated semispecies, each harboring mutualistic Wolbachia strains. Although wild type flies of each semispecies are isolated from the others by both pre- and postmating incompatibilities, mating between semispecies and successful offspring development can be achieved once flies are treated with antibiotics to reduce Wolbachia titer. Here we use RNA-seq to study the impact of Wolbachia on D. paulistorum and investigate the hypothesis that the symbiont may play a role in host speciation. For that goal, we analyze samples of heads and abdomens of both sexes of the Amazonian, Centro American and Orinocan semispecies of D. paulistorum.

    Results: We identify between 175 and 1192 differentially expressed genes associated with a variety of biological processes that respond either globally or according to tissue, sex or condition in the three semispecies. Some of the functions associated with differentially expressed genes are known to be affected by Wolbachia in other species, such as metabolism and immunity, whereas others represent putative novel phenotypes involving muscular functions, pheromone signaling, and visual perception.

    Conclusions: Our results show that Wolbachia affect a large number of biological functions in D. paulistorum, particularly when present in high titer. We suggest that the significant metabolic impact of the infection on the host may cause several of the other putative and observed phenotypes. We also speculate that the observed differential expression of genes associated with chemical communication and reproduction may be associated with the emergence of pre- and postmating barriers between semispecies, which supports a role for Wolbachia in the speciation of D. paulistorum.

  • 94. Bajdek, Piotr
    et al.
    Owocki, Krzysztof
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology.
    Putative dicynodont coprolites from the Upper Triassic of Poland2014In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 411, p. 1-17Article in journal (Refereed)
    Abstract [en]

    A significant number (more than 100) of brownto dark and silty, carbonate or pyrite-mineralized, in part organic carbon-rich, spherical or oval-shaped structures have been collected fromthe Upper Triassic (uppermost NorianlowerRhaetian) sediments of the Lipie Śląskie clay-pit at Lisowice near Lubliniec town, Poland. Their geological context, morphology, content, geochemistry and association with skeletal remains suggest they are fecal masses of a sizable herbivorous tetrapod. The only large herbivore known from the site is a giant 5 meter-long dicynodont (Synapsida: Anomodontia), represented by numerous bones and also by large, oval-shaped footprints. The putative dicynodont coprolites were collected from mudstone and siltstone with numerous organic remains that were deposited in anoxic conditions. In addition, REEs and other trace element concentrations suggest that the burial environment and diagenesis of these coprolites were under anoxic conditions. SEM and thin section images of the coprolite matrix show numerous nests with pyrite (probably bacterial in origin) and large amount of mineral particles. The putative dicynodont coprolites contain also amorphous, dark organic matter, poorly preserved palynomorphs, small fragments of plant cuticle. Detailed characteristic of these coprolites reveals possible implications for the ecology and physiology of the source animal species. The δ 13C values of the gymnospermcuticle and dark organic matter measured in three coprolites are −23.4‰, −21.2‰and −20.3‰, all average. The evidence from these coprolites suggests that dicynodonts processed plant soft elements into very small pieces, but wood fragments were found also in a mass accumulation in two coprolites.

  • 95.
    Bajdek, Piotr
    et al.
    Aleja Najswieztszej Maryi Panny 20-20A, PL-42200 Czestochowa, Poland..
    Qvarnström, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Owocki, Krzysztof
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Sulej, Tomasz
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Sennikov, Andrey G.
    Russian Acad Sci, Borissiak Paleontol Inst, Profsoyuznaya 123, Moscow 117997, Russia.;Kazan Fed Univ, Kremlyovskaya 18, Kazan 420008, Russia..
    Golubev, Valeriy K.
    Russian Acad Sci, Borissiak Paleontol Inst, Profsoyuznaya 123, Moscow 117997, Russia.;Kazan Fed Univ, Kremlyovskaya 18, Kazan 420008, Russia..
    Niedzwiedzki, Grzegorz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Microbiota and food residues including possible evidence of pre-mammalian hair in Upper Permian coprolites from Russia2016In: Lethaia: an international journal of palaeontology and stratigraphy, ISSN 0024-1164, E-ISSN 1502-3931, Vol. 49, no 4, p. 455-477Article in journal (Refereed)
    Abstract [en]

    Coprolites (fossil faeces) provide direct evidence on the diet of its producer and unique insights on ancient food webs and ecosystems. We describe the contents of seven coprolites, collected from the Late Permian Vyazniki site of the European part of Russia. Two coprolite morphotypes (A, B) contain remains of putative bacteria, cyanobacteria, fungi, protists, invertebrate eggs, arthropod elements, undigested bone and tooth fragments, fish scales and elongated hair-like structures with hollow interiors. Content, size and shape of the coprolites together with the associated body fossil record suggest that the most probable scat-producers were carnivorous tetrapods; the bone-rich morphotype A reveals short food retention time and a fast metabolism and is therefore assigned to therapsid carnivores whereas morphotype B with rarer and degraded bones are assigned to archosauromorphs or other non-therapsid carnivores. The general coprolite matrix contains abundant micron-sized spheres and thin-walled vesicles which are interpreted as oxide and phosphatic pseudomorphs after microbial cells. From analyses of the undigested bones, we infer that they represent remains of actinopterygian fish, a therapsid and unrecognizable parts of amphibians and/or reptiles. Additionally, hair-like structures found in one coprolite specimen occur as diagenetically altered (oxide-replaced) structures and moulds (or partly as pseudomorphs) in a microcrystalline carbonate-fluoride-bearing calcium phosphate. This suggests that the latest Permian therapsids probably were equipped with hair-like integument or hairsuit. If true, this is by far the oldest evidence of this mammalian character in the stem group of mammals.

  • 96.
    BALTEKIN, ÖZDEN
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Experimental Evolution of Persister Fractions in Escherichia coli2014Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 97. Baltscheffsky, Herrick
    et al.
    Persson, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Computational and Systems Biology. Uppsala University, Science for Life Laboratory, SciLifeLab.
    On an Early Gene for Membrane-Integral Inorganic Pyrophosphatase in the Genome of an Apparently Pre-LUCA Extremophile, the Archaeon Candidatus Korarchaeum cryptofilum2014In: Journal of Molecular Evolution, ISSN 0022-2844, E-ISSN 1432-1432, Vol. 78, no 2, p. 140-147Article in journal (Refereed)
    Abstract [en]

    A gene for membrane-integral inorganic pyrophosphatase (miPPase) was found in the composite genome of the extremophile archaeon Candidatus Korarchaeum cryptofilum (CKc). This korarchaeal genome shows unusual partial similarity to both major archaeal phyla Crenarchaeota and Euryarchaeota. Thus this Korarchaeote might have retained features that represent an ancestral archaeal form, existing before the occurrence of the evolutionary bifurcation into Crenarchaeota and Euryarchaeota. In addition, CKc lacks five genes that are common to early genomes at the LUCA border. These two properties independently suggest a pre-LUCA evolutionary position of this extremophile. Our finding of the miPPase gene in the CKc genome points to a role for the enzyme in the energy conversion of this very early archaeon. The structural features of its miPPase indicate that it can pump protons through membranes. An miPPase from the extremophile bacterium Caldicellulosiruptor saccharolyticus also has a sequence indicating a proton pump. Recent analysis of the three-dimensional structure of the miPPase from Vigna radiata has resulted in the recognition of a strongly acidic substrate (orthophosphate: Pi, pyrophosphate: PPi) binding pocket, containing 11 Asp and one Glu residues. Asp (aspartic acid) is an evolutionarily very early proteinaceous amino acid as compared to the later appearing Glu (glutamic acid). All the Asp residues are conserved in the miPPase of CKc, V. radiata and other miPPases. The high proportion of Asp, as compared to Glu, seems to strengthen our argument that biological energy conversion with binding and activities of orthophosphate (Pi) and energy-rich pyrophosphate (PPi) in connection with the origin and early evolution of life may have started with similar or even more primitive acidic peptide funnels and/or pockets.

  • 98.
    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
  • 99.
    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.

  • 100.
    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.

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