uu.seUppsala University Publications
Change search
Refine search result
1 - 47 of 47
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the 'Create feeds' function.
  • 1.
    Alexander, Michelle
    et al.
    Univ York, York YO10 5DD, N Yorkshire, England.;Univ Aberdeen, Sch Geosci, Dept Archaeol, Aberdeen AB24 3UF, Scotland..
    Ho, Simon Y. W.
    Univ Sydney, Sch Biol Sci, Sydney, NSW 2006, Australia..
    Molak, Martyna
    Polish Acad Sci, Museum & Inst Zool, PL-00679 Warsaw, Poland..
    Barnett, Ross
    Palaeogen & Bioarchaeol Res Network, Res Lab Archaeol, Oxford OX1 3QY, England..
    Carlborg, Örjan
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Dorshorst, Ben
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Virginia Tech, Dept Anim & Poultry Sci, Blacksburg, VA 24061 USA..
    Honaker, Christa
    Virginia Tech, Dept Anim & Poultry Sci, Blacksburg, VA 24061 USA..
    Besnier, Francois
    Inst Marine Res, Sect Populat Genet, N-5024 Bergen, Norway..
    Wahlberg, Per
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Sciences, Molecular Medicine.
    Dobney, Keith
    Univ Aberdeen, Sch Geosci, Dept Archaeol, Aberdeen AB24 3UF, Scotland..
    Siegel, Paul
    Virginia Tech, Dept Anim & Poultry Sci, Blacksburg, VA 24061 USA..
    Andersson, Leif
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology. Swedish Univ Agr Sci, Dept Anim Breeding & Genet, S-75007 Uppsala, Sweden..
    Larson, Greger
    Palaeogen & Bioarchaeol Res Network, Res Lab Archaeol, Oxford OX1 3QY, England..
    Mitogenomic analysis of a 50-generation chicken pedigree reveals a rapid rate of mitochondrial evolution and evidence for paternal mtDNA inheritance2015In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 11, no 10, 20150561Article in journal (Refereed)
    Abstract [en]

    Mitochondrial genomes represent a valuable source of data for evolutionary research, but studies of their short-term evolution have typically been limited to invertebrates, humans and laboratory organisms. Here we present a detailed study of 12 mitochondrial genomes that span a total of 385 transmissions in a well-documented 50-generation pedigree in which two lineages of chickens were selected for low and high juvenile body weight. These data allowed us to test the hypothesis of time-dependent evolutionary rates and the assumption of strict maternal mitochondrial transmission, and to investigate the role of mitochondrial mutations in determining phenotype. The identification of a non-synonymous mutation in ND4L and a synonymous mutation in CYTB, both novel mutations in Gallus, allowed us to estimate a molecular rate of 3.13 x 10(-7) mutations/site/year (95% confidence interval 3.75 x 10(-8)-1.12 x 10(-6)). This is substantially higher than avian rate estimates based upon fossil calibrations. Ascertaining which of the two novel mutations was present in an additional 49 individuals also revealed an instance of paternal inheritance of mtDNA. Lastly, an association analysis demonstrated that neither of the point mutations was strongly associated with the phenotypic differences between the two selection lines. Together, these observations reveal the highly dynamic nature of mitochondrial evolution over short time periods.

  • 2.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Jones, Theresa M.
    Elgar, Mark A.
    Sex-role reversed nuptial feeding reduces male kleptoparasitism of females in Zeus bugs (Heteroptera: Veliidae)2006In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 2, no 4, 491-493 p.Article in journal (Refereed)
    Abstract [en]

    Males of a variety of taxa occasionally steal food secured by their mates. In some spiders and insects, males rely entirely on this form of intraspecific kleptoparasitism for their subsistence. However, this male strategy may be costly for females and a variety of different female counteradaptations have been proposed. In Zeus bugs ( Phoreticovelia spp.), males ride on the back of their mates for extended periods and females produce a gland secretion that males feed on. By experimentally occluding the dorsal glands in females and varying food availability, we show that nuptial feeding by females reduces the extent to which the males kleptoparasitize their mates. We suggest that females have, at least in part, evolved this unique form of nuptial feeding as a counteradaptation to reduce the rate of kleptoparasitism by males.

  • 3.
    Backström, Niclas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Ellegren, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Levels of linkage disequilibrium in a wild bird population2006In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 2, no 3, 435-438 p.Article in journal (Refereed)
    Abstract [en]

    Population-based mapping approaches are attractive for tracing the genetic background to phenotypic traits in wild species, given that it is often difficult to gather extensive and well-defined pedigrees needed for quantitative trait locus analysis. However, the feasibility of association or hitch-hiking mapping is dependent on the degree of linkage disequilibrium. (LD) in the population, on which there is yet limited information for wild species. Here we use single nucleotide polymorphism (SNP) markers from 23 genes in a recently established linkage map of the Z chromosome of the collared flycatcher, to study the extent of LD in a natural bird population. In most but not all cases we find SNPs within the same intron (less than 500 bp) to be in perfect LD. However, LD then decays to background level at a distance 1 cM or 400-500 kb. Although LD seems more extensive than in other species, if the observed pattern is representative for other regions of the genome and turns out to be a general feature of natural bird populations, dense marker maps might be needed for genome scans aimed at identifying association between marker and trait loci.

  • 4. Barrett, Paul M.
    et al.
    Evans, David C.
    Campione, Nicolas E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Evolution of dinosaur epidermal structures2015In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 11, no 6, 20150229Article in journal (Refereed)
    Abstract [en]

    Spectacularly preserved non-avian dinosaurs with integumentary filaments/feathers have revolutionized dinosaur studies and fostered the suggestion that the dinosaur common ancestor possessed complex integumentary structures homologous to feathers. This hypothesis has major implications for interpreting dinosaur biology, but has not been tested rigorously. Using a comprehensive database of dinosaur skin traces, we apply maximum-likelihood methods to reconstruct the phylogenetic distribution of epidermal structures and interpret their evolutionary history. Most of these analyses find no compelling evidence for the appearance of protofeathers in the dinosaur common ancestor and scales are usually recovered as the plesiomorphic state, but results are sensitive to the outgroup condition in pterosaurs. Rare occurrences of ornithischian filamentous integument might represent independent acquisitions of novel epidermal structures that are not homologous with theropod feathers.

  • 5.
    Belli, Phil R.
    et al.
    Univ New England, Armidale, NSW 2351, Australia..
    Campione, Nicolas E.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Persons, W. Scott
    Univ Alberta, Edmonton, AB T6E 4S6, Canada..
    Currie, Philip J.
    Univ Alberta, Edmonton, AB T6E 4S6, Canada..
    Larson, Peter L.
    Geol Res Inc, Black Hills Inst, Hill City, SD 57745 USA..
    Tanke, Darren H.
    Royal Tyrrell Museum Palaeontol, Drumheller, AB, Canada..
    Bakker, Robert T.
    Houston Museum Nat Sci, Houston, TX 77030 USA..
    Tyrannosauroid integument reveals conflicting patterns of gigantism and feather evolution2017In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 13, no 6, 20170092Article in journal (Refereed)
    Abstract [en]

    Recent evidence for feathers in theropods has led to speculations that the largest tyrannosaurids, including Tyrannosaurus rex, were extensively feathered. We describe fossil integument from Tyrannosaurus and other tyrannosaurids (Albertosaurus, Daspletosaurus, Gorgosaurus and Tarbosaurus), confirming that these large-bodied forms possessed scaly, reptilian-like skin. Body size evolution in tyrannosauroids reveals two independent occurrences of gigantism; specifically, the large sizes in Yutyrannus and tyrannosaurids were independently derived. These new findings demonstrate that extensive feather coverings observed in some early tyrannosauroids were lost by the Albian, basal to Tyrannosauridae. This loss is unrelated to palaeoclimate but possibly tied to the evolution of gigantism, although other mechanisms exist.

  • 6.
    Bize, Pierre
    et al.
    Univ Aberdeen, Inst Biol & Environm Sci, Aberdeen, Scotland.;Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland..
    Daniel, Gregory
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ Claude Bernard Lyon 1, Lab Biometrie & Biol Evolut, CNRS, Villeurbanne, France.
    Viblanc, Vincent A.
    Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland.;Univ Strasbourg, CNRS, UMR 7178, IPHC, F-67000 Strasbourg, France..
    Martin, Julien G. A.
    Univ Aberdeen, Inst Biol & Environm Sci, Aberdeen, Scotland..
    Doligez, Blandine
    Univ Claude Bernard Lyon 1, Lab Biometrie & Biol Evolut, CNRS, Villeurbanne, France..
    Negative phenotypic and genetic correlation between natal dispersal propensity and nest-defence behaviour in a wild bird2017In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 13, no 7, 20170236Article in journal (Refereed)
    Abstract [en]

    Natural selection is expected to favour the integration of dispersal and phenotypic traits allowing individuals to reduce dispersal costs. Accordingly, associations have been found between dispersal and personality traits such as aggressiveness and exploration, which may facilitate settlement in a novel environment. However, the determinism of these associations has only rarely been explored. Here, we highlight the functional integration of individual personality in nest-defence behaviour and natal dispersal propensity in a long-lived colonial bird, the Alpine swift (Alms melba), providing insights into genetic constraints shaping the coevolution of these two traits. We report a negative association between natal dispersal and nest-defence (i.e. risk taking) behaviour at both the phenotypic and genetic level. This negative association may result from direct selection if risk-averseness benefits natal dispersers by reducing the costs of settlement in an unfamiliar environment, or from indirect selection if individuals with lower levels of nest defence also show lower levels of aggressiveness, reducing costs of settlement among unfamiliar neighbours in a colony. In both cases, these results highlight that risk taking is an important behavioural trait to consider in the study of dispersal evolution.

  • 7.
    Brown, Caleb M.
    et al.
    Tyrrell Museum of Paleontology.
    Campione, Nicolas E.
    Department of Ecology and Evolutionary Biology, University of Toronto, Ontario, Canada.
    Giacomini, Henrique C.
    University of Toronto.
    O'Brien, Lorna J.
    University of Toronto.
    Vavrek, Matthew J.
    Philip J. Currie Dinosaur Museum.
    Evans, David C.
    Royal Ontario Museum.
    Ecological modelling, size distributions and taphonomic size bias in dinosaur faunas: a comment on Codron et al. (2012)2013In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 9, no 1, 20120582- p.Article in journal (Refereed)
  • 8.
    Chen, Hwei-yen
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Zajitschek, Felix
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Maklakov, Alexei A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Why ageing stops: heterogeneity explains late-life mortality deceleration in nematodes2013In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 9, no 5, 20130217- p.Article in journal (Refereed)
    Abstract [en]

    While ageing is commonly associated with exponential increase in mortality with age, mortality rates paradoxically decelerate late in life resulting in distinct mortality plateaus. Late-life mortality plateaus have been discovered in a broad variety of taxa, including humans, but their origin is hotly debated. One hypothesis argues that deceleration occurs because the individual probability of death stops increasing at very old ages, predicting the evolution of earlier onset of mortality plateaus under increased rate of extrinsic mortality. By contrast, heterogeneity theory suggests that mortality deceleration arises from individual differences in intrinsic lifelong robustness and predicts that variation in robustness between populations will result in differences in mortality deceleration. We used experimental evolution to directly test these predictions by independently manipulating extrinsic mortality rate (high or low) and mortality source (random death or condition-dependent) to create replicate populations of nematodes, Caenorhabditis remanei that differ in the strength of selection in late-life and in the level of lifelong robustness. Late-life mortality deceleration evolved in response to differences in mortality source when mortality rate was held constant, while there was no consistent response to differences in mortality rate. These results provide direct experimental support for the heterogeneity theory of late-life mortality deceleration.

  • 9. Cunningham, John A.
    et al.
    Ruecklin, Martin
    Blom, Henning
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Evolution and Developmental Biology.
    Botella, Hector
    Donoghue, Philip C. J.
    Testing models of dental development in the earliest bony vertebrates, Andreolepis and Lophosteus2012In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 8, no 5, 833-837 p.Article in journal (Refereed)
    Abstract [en]

    Theories on the development and evolution of teeth have long been biased by the fallacy that chondrichthyans reflect the ancestral condition for jawed vertebrates. However, correctly resolving the nature of the primitive vertebrate dentition is challenged by a dearth of evidence on dental development in primitive osteichthyans. Jaw elements from the Silurian-Devonian stem-osteichthyans Lophosteus and Andreolepis have been described to bear a dentition arranged in longitudinal rows and vertical files, reminiscent of a pattern of successional development. We tested this inference, using synchrotron radiation X-ray tomographic microscopy (SRXTM) to reveal the pattern of skeletal development preserved in the sclerochronology of the mineralized tissues. The tooth-like tubercles represent focal elaborations of dentine within otherwise continuous sheets of the dermal skeleton, present in at least three stacked generations. Thus, the tubercles are not discrete modular teeth and their arrangement into rows and files is a feature of the dermal ornamentation that does not reflect a polarity of development or linear succession. These fossil remains have no bearing on the nature of the dentition in osteichthyans and, indeed, our results raise questions concerning the homologies of these bones and the phylogenetic classification of Andreolepis and Lophosteus.

  • 10. Ericson, Per G. P.
    et al.
    Anderson, Cajsa Lisa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Systematic Botany.
    Britton, Tom
    Elzanowski, Andrzej
    Johansson, Ulf S.
    Källersjö, Mari
    Ohlson, Jan I.
    Parsons, Thomas J.
    Zuccon, Dario
    Mayr, Gerald
    Diversification of Neoaves through time: Integration of molecular sequence data and fossils2006In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 2, no 4, 543-547 p.Article in journal (Refereed)
    Abstract [en]

    Patterns of diversification and timing of evolution within Neoaves, which includes almost 95% of all bird species, are virtually unknown. On the other hand, molecular data consistently indicate a Cretaceous origin of many neoavian lineages and the fossil record seems to support an Early Tertiary diversification. Here, we present the first well-resolved molecular phylogeny for Neoaves, together with divergence time estimates calibrated with a large number of stratigraphically and phylogenetically well-documented fossils. Our study defines several well-supported clades within Neoaves. The calibration results suggest that Neoaves, after an initial split from Galloanseres in Mid-Cretaceous, diversified around or soon after the K/T boundary. Our results thus do not contradict palaeontological data and show that there is no solid molecular evidence for an extensive pre-Tertiary radiation of Neoaves.

  • 11. Ericson, Per G. P.
    et al.
    Anderson, Cajsa Lisa
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics.
    Mayr, Gerald
    Hangin’ on to our rocks ’n clocks: a reply to Brown et al.2007In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 3, no 3, 260-261 p.Article in journal (Refereed)
  • 12.
    Ettema, Thijs J. G.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Molecular Evolution.
    Andersson, Siv G. E.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Molecular Evolution.
    The alpha-proteobacteria: the Darwin finches of the bacterial world2009In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 5, no 3, 429-432 p.Article in journal (Refereed)
    Abstract [en]

    The alpha-proteobacteria represent one of the most diverse bacterial subdivisions, displaying extreme variations in lifestyle, geographical distribution and genome size. Species for which genome data are available have been classified into a species tree based on a conserved set of vertically inherited core genes. By mapping the variation in gene content onto the species tree, genomic changes can be associated with adaptations to specific growth niches. Genes for adaptive traits are mostly located in 'plasticity zones' in the bacterial genome, which also contain mobile elements and are highly variable across strains. By physically separating genes for information processing from genes involved in interactions with the surrounding environment, the rate of evolutionary change can be substantially enhanced for genes underlying adaptation to new growth habitats, possibly explaining the ecological success of the alpha-proteobacterial subdivision.

  • 13.
    Falck-Ytter, Terje
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Psychology.
    Young children with autism spectrum disorder use predictive eye movements in action observation2010In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 6, no 3, 375-378 p.Article in journal (Refereed)
    Abstract [en]

    Does a dysfunction in the mirror neuron system (MNS) underlie the social symptoms defining autism spectrum disorder (ASD)? Research suggests that the MNS matches observed actions to motor plans for similar actions, and that these motor plans include directions for predictive eye movements when observing goal-directed actions. Thus, one important question is whether children with ASD use predictive eye movements in action observation. Young children with ASD as well as typically developing children and adults were shown videos in which an actor performed object-directed actions (human agent condition). Children with ASD were also shown control videos showing objects moving by themselves (self-propelled condition). Gaze was measured using a corneal reflection technique. Children with ASD and typically developing individuals used strikingly similar goal-directed eye movements when observing others' actions in the human agent condition. Gaze was reactive in the self-propelled condition, suggesting that prediction is linked to seeing a hand-object interaction. This study does not support the view that ASD is characterized by a global dysfunction in the MNS.

  • 14. Freeman, Robin
    et al.
    Mann, Richard
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics, Analysis and Applied Mathematics.
    Guilford, Tim
    Biro, Dora
    Group decisions and individual differences: route fidelity predicts flight leadership in homing pigeons (Columba livia)2011In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 7, no 1, 63-66 p.Article in journal (Refereed)
    Abstract [en]

    How social-living animals make collective decisions is currently the subject of intense scientific interest, with increasing focus on the role of individual variation within the group. Previously, we demonstrated that during paired flight in homing pigeons, a fully transitive leadership hierarchy emerges as birds are forced to choose between their own and their partner's habitual routes. This stable hierarchy suggests a role for individual differences mediating leadership decisions within homing pigeon pairs. What these differences are, however, has remained elusive. Using novel quantitative techniques to analyse habitual route structure, we show here that leadership can be predicted from prior route-following fidelity. Birds that are more faithful to their own route when homing alone are more likely to emerge as leaders when homing socially. We discuss how this fidelity may relate to the leadership phenomenon, and propose that leadership may emerge from the interplay between individual route confidence and the dynamics of paired flight.

  • 15.
    Friberg, Urban
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Stewart, Andrew D.
    Rice, William R.
    X- and Y-chromosome linked paternal effects on a life-history trait2012In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 8, no 1, 71-73 p.Article in journal (Refereed)
    Abstract [en]

    Males and females usually invest asymmetrically in offspring. In species lacking parental care, females influence offspring in many ways, while males only contribute genetic material via their sperm. For this reason, maternal effects have long been considered an important source of phenotypic variation, while paternal effects have been presumed to be absent or negligible. The recent surge of studies showing trans-generational epigenetic effects questions this assumption, and indicates that paternal effects may be far more important than previously appreciated. Here, we test for sex-linked paternal effects in Drosophila melanogaster on a life-history trait, and find substantial support for both X- and Y-linked effects.

  • 16.
    Hailer, Frank
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Helander, B.
    Folkestad, A. O.
    Ganusevich, S. A.
    Garstad, S.
    Hauff, P.
    Koren, C.
    Nygård, T.
    Volke, V.
    Vilà, Carles
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Ellegren, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Bottlenecked but long-lived: high genetic diversity retained in white-tailed eagles upon recovery from population decline2006In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 2, no 2, 316-319 p.Article in journal (Refereed)
    Abstract [en]

    Most of the white-tailed eagle (Haliaeetus albicilla) populations in Europe experienced dramatic declines during the twentieth century. However, owing to intense conservation actions and the ban of DDT and other persistent pollutants, populations are currently recovering. We show that despite passing through demographic bottlenecks, white-tailed eagle populations have retained significant levels of genetic diversity. Both genetic and ringing data indicate that migration between populations has not been a major factor for the maintenance of genetic variability. We argue that the long generation time of eagles has acted as an intrinsic buffer against loss of genetic diversity, leading to a shorter effective time of the experienced bottleneck. Notably, conservation actions taken in several small sub-populations have ensured the preservation of a larger proportion of the total genetic diversity than if conservation had focused on the population stronghold in Norway. For conservation programmes targeting other endangered, long-lived species, our results highlight the possibility for local retention of high genetic diversity in isolated remnant populations.

  • 17.
    Herbert-Read, James E.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics.
    Romenskyy, Maxym
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics.
    Sumpter, David J. T.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics.
    A Turing test for collective motion2015In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 11, no 12, 20150674Article in journal (Refereed)
    Abstract [en]

    A widespread problem in biological research is assessing whether a model adequately describes some real-world data. But even if a model captures the large-scale statistical properties of the data, should we be satisfied with it? We developed a method, inspired by Alan Turing, to assess the effectiveness of model fitting. We first built a self-propelled particle model whose properties (order and cohesion) statistically matched those of real fish schools. We then asked members of the public to play an online game (a modified Turing test) in which they attempted to distinguish between the movements of real fish schools or those generated by the model. Even though the statistical properties of the real data and the model were consistent with each other, the public could still distinguish between the two, highlighting the need for model refinement. Our results demonstrate that we can use 'citizen science' to cross-validate and improve model fitting not only in the field of collective behaviour, but also across a broad range of biological systems.

  • 18.
    Heuschele, Jan
    et al.
    Department of Biological and Environmental Sciences, University of Helsinki.
    Candolin, Ulrika
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    An increase in pH boosts olfactory communication in sticklebacks2007In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 3, no 4, 411-413 p.Article in journal (Refereed)
    Abstract [en]

    Human-induced eutrophication is a serious environmental problem that constrains visual communication and influences the mate choice process in fishes. Eutrophication also changes the chemical environment and the pH of the water, which could influence the use of olfactory cues in mate choice. Here, we show that an increase in pH enhances the use of male olfactory cues in mate choice in three-spined sticklebacks, Gasterosteus aculeatus. In a laboratory choice experiment, gravid females were more attracted to male olfactory cues when pH was raised. This could compensate for impaired visual communication in eutrophied waters and facilitate adaptive mate choice.

  • 19. Ho, Simon Y. W.
    et al.
    Larson, Greger
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Edwards, Ceiridwen J.
    Heupink, Tim H.
    Lakin, Kay E.
    Holland, Peter W. H.
    Shapiro, Beth
    Correlating Bayesian date estimates with climatic events and domestication using a bovine case study.2008In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 4, no 4, 370-374 p.Article in journal (Refereed)
    Abstract [en]

    The tribe Bovini contains a number of commercially and culturally important species, such as cattle. Understanding their evolutionary time scale is important for distinguishing between post-glacial and domestication-associated population expansions, but estimates of bovine divergence times have been hindered by a lack of reliable calibration points. We present a Bayesian phylogenetic analysis of 481 mitochondrial D-loop sequences, including 228 radiocarbon-dated ancient DNA sequences, using a multi-demographic coalescent model. By employing the radiocarbon dates as internal calibrations, we co-estimate the bovine phylogeny and divergence times in a relaxed-clock framework. The analysis yields evidence for significant population expansions in both taurine and zebu cattle, European aurochs and yak clades. The divergence age estimates support domestication-associated expansion times (less than 12 kyr) for the major haplogroups of cattle. We compare the molecular and palaeontological estimates for the Bison-Bos divergence.

  • 20.
    Holmer, Lars Erik
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Skovsted, C.B.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Brock, G.A.
    Paterson, J.A.
    The Early Cambrian tommotiid Micrina, a sessile bivalved stem group brachiopod2008In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 4, no 6, 724-728 p.Article in journal (Refereed)
    Abstract [en]

    The tannuolinid Micrina belongs to the tommotiids—a common and widely distributed, but poorly understood, group of Early Cambrian fossil metazoans with multiple external organophosphatic sclerites. Recent findings of sessile articulated tommotiid scleritomes indicate that previous reconstructions of tommotiids as slug-like bilaterians with a dorsal cover of sclerites require detailed re-evaluation. Comparative ultrastructural work has already indicated that the tommotiids might be a sister group to the Brachiopoda, with Micrina representing the most derived and brachiopod-like bimembrate tommotiid. Here we further develop and strengthen this controversial phylogenetic model with a new reconstruction of Micrina, where the two types of sclerites—mitral and sellate—belong to a near bilaterally symmetrical bivalved sessile organism. This new scleritome configuration was tested by recreating an articulated bivalved Micrina from isolated mitral and sellate sclerites; both sclerites have muscles that would have enabled movement of the sclerites. The mitral and sellate sclerites of Micrina are considered to be homologous with the ventral and dorsal valves, respectively, of organophosphatic linguliform brachiopods, indicating that a simple type of filter-feeding within an enclosed bivalved shell had started to evolve in derived tannuolinids. The new reconstruction also indicates that the phylogenetic range of ‘bivalved’, sessile lophophorates is larger than previously suspected.

  • 21.
    Immler, Simone
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Hotzy, Cosima
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Alavioon, Ghazal
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Petersson, Erik
    Arnqvist, Goran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Sperm variation within a single ejaculate affects offspring development in Atlantic salmon2014In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 10, no 2, 20131040- p.Article in journal (Refereed)
    Abstract [en]

    It is generally believed that variation in sperm phenotype within a single ejaculate has no consequences for offspring performance, because sperm phenotypes are thought not to reflect sperm genotypes. We show that variation in individual sperm function within an ejaculate affects the performance of the resulting offspring in the Atlantic salmon Salmo salar. We experimentally manipulated the time between sperm activation and fertilization in order to select for sperm cohorts differing in longevity within single ejaculates of wild caught male salmon. We found that within-ejaculate variation in sperm longevity significantly affected offspring development and hence time until hatching. Whether these effects have a genetic or epigenetic basis needs to be further evaluated. However, our results provide experimental evidence for transgenerational effects of individual sperm function.

  • 22. Johnson, Steven D.
    et al.
    Torninger, Erica
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Ecological Botany.
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Ecological Botany.
    Relationships between population size and pollen fates in a moth-pollinated orchid2009In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 5, no 2, 282-285 p.Article in journal (Refereed)
    Abstract [en]

    Management of small plant populations requires an understanding of their reproductive ecology, particularly in terms of sensitivity to Allee effects. To address this issue, we explored how components of pollen transfer and pollination success of individual plants varied among 36 populations of the self-compatible moth-pollinated orchid Satyrium longicauda in South Africa. Mean fruit set, seed production, proportion of flowers with pollen deposited or removed and proportion of removed pollen that reached stigmas (approx. 8% in this species) were not significantly related to population size (range: 1–450 flowering individuals), density or isolation. Plants in small populations did, however, have significantly higher levels of pollinator-mediated self-pollination (determined using colour-labelled pollen) than those in larger populations. Our results suggest that small populations of this orchid species are resilient to Allee effects in terms of overall pollination success, although the higher levels of pollinator-mediated self-pollination in small populations may lead to inbreeding depression and long-term erosion of genetic diversity.

  • 23. Kallio, Eva R.
    et al.
    Henttonen, Heikki
    Koskela, Esa
    Lundkvist, Åke
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Mappes, Tapio
    Vapalahti, Olli
    Maternal antibodies contribute to sex-based difference in hantavirus transmission dynamics2013In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 9, no 6, 20130887- p.Article in journal (Refereed)
    Abstract [en]

    Individuals often differ in their ability to transmit disease and identifying key individuals for transmission is a major issue in epidemiology. Male hosts are often thought to be more important than females for parasite transmission and persistence. However, the role of infectious females, particularly the transient immunity provided to offspring through maternal antibodies (MatAbs), has been neglected in discussions about sex-biased infection transmission. We examined the effect of host sex upon infection dynamics of zoonotic Puumala hantavirus (PUUV) in semi-natural, experimental populations of bank vole (Myodes glareolus). Populations were founded with either females or males that were infected with PUUV, whereas the other sex was immunized against PUUV infection. The likelihood of the next generation being infected was lower when the infected founders were females, underlying the putative importance of adult males in PUUV transmission and persistence in host populations. However, we show that this effect probably results from transient immunity that infected females provide to their offspring, rather than any sex-biased transmission efficiency per se. Our study proposes a potential contrasting nature of female and male hosts in the transmission dynamics of hantaviruses.

  • 24. Koblmueller, Stephan
    et al.
    Wayne, Robert K.
    Leonard, Jennifer A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Impact of Quaternary climatic changes and interspecific competition on the demographic history of a highly mobile generalist carnivore, the coyote2012In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 8, no 4, 644-647 p.Article in journal (Refereed)
    Abstract [en]

    Recurrent cycles of climatic change during the Quaternary period have dramatically affected the population genetic structure of many species. We reconstruct the recent demographic history of the coyote (Canis latrans) through the use of Bayesian techniques to examine the effects of Late Quaternary climatic perturbations on the genetic structure of a highly mobile generalist species. Our analysis reveals a lack of phylogeographic structure throughout the range but past population size changes correlated with climatic changes. We conclude that even generalist carnivorous species are very susceptible to environmental changes associated with climatic perturbations. This effect may be enhanced in coyotes by interspecific competition with larger carnivores.

  • 25.
    Leonard, Jennifer A
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Wayne, Robert K
    Native Great Lakes wolves were not restored2008In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 4, no 1, 95-98 p.Article in journal (Refereed)
    Abstract [en]

    Wolves from the Great Lakes area were historically decimated due to habitat loss and predator control programmes. Under the protection of the US Endangered Species Act, the population has rebounded to approximately 3000 individuals. We show that the pre-recovery population was dominated by mitochondrial DNA haplotypes from an endemic American wolf referred to here as the Great Lakes wolf. In contrast, the recent population is admixed, and probably derives also from the grey wolf (Canis lupus) of Old World origin and the coyote (Canis latrans). Consequently, the pre-recovery population has not been restored, casting doubt on delisting actions.

  • 26.
    Leonard, Jennifer A.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Wayne, Robert K.
    University of California.
    Wishful thinking: Imagining that the current Great Lakes wolf is the same entity that existed historically2009In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 5, no 1, 67-68 p.Article in journal (Refereed)
  • 27. Lohmus, Mare
    et al.
    Moalem, Sharon
    Björklund, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal Ecology.
    Leptin, a tool of parasites?2012In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 8, no 5, 849-852 p.Article in journal (Refereed)
    Abstract [en]

    One common physiological phenomenon that is involved both in infectious and in malignant processes is the reduction in appetite: disease anorexia. An increase in plasma levels of leptin with inflammation is thought to be involved in this process. However, from an evolutionary perspective, in certain cases, it would be more adaptive for an internal parasite to stimulate the appetite of the host instead of causing its suppression. We tested whether a parasitic infection with the larvae of the helminth parasite Taenia taeniaformis affects the levels of appetite-regulating proteins, such as leptin, ghrelin and neuropeptide-Y (NPY) in wild yellow-necked mouse (Apodemus flavicollis). We found that infected mice had lower plasma levels of leptin and increased levels of NPY than the uninfected subjects. Ghrelin levels were not associated with the occurrence of the parasites; however, these levels strongly correlated with the levels of NPY. This study suggests a possible manipulation by parasitic larvae of appetite regulation in infected subjects.

  • 28.
    Lönnstedt, Oona
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Limnology.
    Ferrari, Maud C.O.
    Chivers, Douglas P.
    Lionfish predators used flared fin displays to initiate cooperative hunting2014In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 10, no 6, 20140281- p.Article in journal (Refereed)
    Abstract [en]

    Despite considerable study, mystery surrounds the use of signals that initiate cooperative hunting in animals. Using a labyrinth test chamber, we examined whether a lionfish, Dendrochirus zebra, would initiate cooperative hunts with piscine partners. We found that D. zebra uses a stereotyped flared fin display to alert conspecific and heterospecific lionfish species Pterois antennata to the presence of prey. Per capita success rate was significantly higher for cooperative hunters when compared with solitary ones, with hunt responders assisting hunt initiators in cornering the prey using their large extended pectoral fins. The initiators would most often take the first strike at the group of prey, but both hunters would then alternate striking at the remaining prey. Results suggest that the cooperative communication signal may be characteristic to the lionfish family, as interspecific hunters were equally coordinated and successful as intraspecific hunters. Our findings emphasize the complexity of collaborative foraging behaviours in lionfish; the turn-taking in strikes suggests that individuals do not solely try to maximize their own hunting success: instead they equally share the resources between themselves. Communicative group hunting has enabled Pteroine fish to function as highly efficient predators.

  • 29.
    Maklakov, Alexei A.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal Ecology.
    Immler, Simone
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Gonzalez-Voyer, Alejandro
    Rönn, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Kolm, Niclas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal Ecology.
    Brains and the city: big-brained passerine birds succeed in urban environments2011In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 7, no 5, 730-732 p.Article in journal (Refereed)
    Abstract [en]

    Urban regions are among the most human-altered environments on Earth and they are poised for rapid expansion following population growth and migration. Identifying the biological traits that determine which species are likely to succeed in urbanized habitats is important for predicting global trends in biodiversity. We provide the first evidence for the intuitive yet untested hypothesis that relative brain size is a key factor predisposing animals to successful establishment in cities. We apply phylogenetic mixed modelling in a Bayesian framework to show that passerine species that succeed in colonizing at least one of 12 European cities are more likely to belong to big-brained lineages than species avoiding these urban areas. These data support findings linking relative brain size with the ability to persist in novel and changing environments in vertebrate populations, and have important implications for our understanding of recent trends in biodiversity.

  • 30.
    Maklakov, Alexei A.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Immler, Simone
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Gonzalez-Voyer, Alejandro
    Rönn, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Kolm, Niclas
    Brains and the city in passerine birds: re-analysis and confirmation of the original result2013In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 9, no 6, 20130859- p.Article in journal (Refereed)
    Abstract [en]

    Our original paper [1] included two Bayesian analyses [2] of the association between brain size and the probability of a passerine species of bird breeding in the city centre—at the level of families and at the level of individual species—with both analyses suggesting the same pattern. It has since been brought to our attention that in one of the analyses at the level of individual species, the residual variance was not fixed to 1 resulting in overestimation of the variance. We re-ran the analysis using fixed residual variance and the results support the original conclusion that relative brain size is associated with breeding in the city centre (ln brain size: posterior mean, 324.53, 95% credibility interval, 52.61–601.35; ln body size: posterior mean, −276.22, 95% credibility interval, −490.60 to −70.32). Furthermore, we applied a complimentary approach using logistic regression to test whether brain size predicts breeding in the city centre (yes/no) without accounting for phylogeny. This analysis also resulted in a significant positive association between brain size and breeding in city centres (likelihood ratio tests: ln brain size: d.f. = 1, χ2 = 11.08, p = 0.0009; ln body size: d.f. = 1, χ2 = 11.26, p = 0.0008). Thus, our results are confirmed by both phylogenetic and non-phylogenetic analyses.

  • 31.
    Maklakov, Alexei A.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Kremer, Natacha
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Arnqvist, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Ageing and the evolution of female resistance to remating in seed beetles2006In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 2, no 1, 62-64 p.Article in journal (Refereed)
    Abstract [en]

    Female remating behaviour is a key mating system parameter that is predicted to evolve according to the net effect of remating on female fitness. In many taxa, females commonly resist male remating attempts because of the costs of mating. Here, we use replicated populations of the seed beetle Acanthoscelides obtectus selected for either early or late life reproduction and show that 'Early' and 'Late' females evolved different age-specific rates of remating. Early females were more likely to remate with control males as they aged, while Late females were more resistant to remating later in life. Thus, female remating rate decreases with age when direct selection on late-life fitness is operating and increases when such selection is relaxed. Our findings not only demonstrate that female resistance to remating can evolve rapidly, but also that such evolution is in accordance with the genetic interests of females.

  • 32.
    Mank, Judith E
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Ellegren, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Are sex-biased genes more dispensable?2009In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 5, no 3, 409-412 p.Article in journal (Refereed)
    Abstract [en]

    Many genes show different expression levels in males and females, and these form the basis of sexually dimorphic phenotypes. Sex-biased genes experience accelerated rates of protein evolution, which has been attributed to sexual selection. However, it is possible that the increased rates of molecular evolution, and more importantly the sex-biased gene expression pattern itself, are due to decreased selective constraint. This notion may explain many of the patterns associated with sex-biased gene expression, and changes how we should view the role of natural and sexual selection in relation to these genes.

  • 33.
    Mann, Richard P.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Mathematics.
    Armstrong, Chris
    Meade, Jessica
    Freeman, Robin
    Biro, Dora
    Guilford, Tim
    Landscape complexity influences route-memory formation in navigating pigeons2014In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 10, no 1, 20130885- p.Article in journal (Refereed)
    Abstract [en]

    Observations of the flight paths of pigeons navigating from familiar locations have shown that these birds are able to learn and subsequently follow habitual routes home. It has been suggested that navigation along these routes is based on the recognition of memorized visual landmarks. Previous research has identified the effect of landmarks on flight path structure, and thus the locations of potentially salient sites. Pigeons have also been observed to be particularly attracted to strong linear features in the landscape, such as roads and rivers. However, a more general understanding of the specific characteristics of the landscape that facilitate route learning has remained out of reach. In this study, we identify landscape complexity as a key predictor of the fidelity to the habitual route, and thus conclude that pigeons form route memories most strongly in regions where the landscape complexity is neither too great nor too low. Our results imply that pigeons process their visual environment on a characteristic spatial scale while navigating and can explain the different degrees of success in reproducing route learning in different geographical locations.

  • 34.
    McFarlane, S. Eryn
    et al.
    Department of Integrative Biology, University of Guelph.
    Lane, Jeffrey E.
    Taylor, Ryan W.
    Gorrell, Jamieson C.
    Coltman, David W.
    Humphries, Murray M.
    Boutin, Stan
    McAdam, Andrew G.
    The heritability of multiple male mating in a promiscuous mammal2011In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 7, no 3, 368-371 p.Article in journal (Refereed)
    Abstract [en]

    The tendency of females to mate with multiple males is often explained by direct and indirect benefits that could outweigh the many potential costs of multiple mating. However, behaviour can only evolve in response to costs and benefits if there is sufficient genetic variation on which selection can act. We followed 108 mating chases of 85 North American red squirrels (Tamiasciurus hudsonicus) during 4 years, to measure each female's degree of multiple male mating (MMM), and used an animal model analysis of our multi-generational pedigree to provide what we believe is the first estimate of the heritability of MMM in the wild. Female red squirrels were highly polyandrous, mating with an average of 7.0 ± 0.2 males on their day of oestrus. Although we found evidence for moderate levels of additive genetic variation (CVA = 5.1), environmental variation was very high (CVE = 32.3), which resulted in a very low heritability estimate (h2 < 0.01). So, while there is genetic variation in this trait, the large environmental variation suggests that any costs or benefits associated with differences among females in MMM are primarily owing to environmental and not genetic differences, which could constrain the evolutionary response to natural selection on this trait.

  • 35.
    McFarlane, S. Eryn
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Söderberg, Axel
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Wheatcroft, David
    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.
    Song discrimination by nestling collared flycatchers during early development2016In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 12, no 7, 20160234Article in journal (Refereed)
    Abstract [en]

    Pre-zygotic isolation is often maintained by species-specific signals and preferences. However, in species where signals are learnt, as in songbirds, learning errors can lead to costly hybridization. Song discrimination expressed during early developmental stages may ensure selective learning later in life but can be difficult to demonstrate before behavioural responses are obvious. Here, we use a novel method, measuring changes in metabolic rate, to detect song perception and discrimination in collared flycatcher embryos and nestlings. We found that nestlings as early as 7 days old respond to song with increased metabolic rate, and, by 9 days old, have increased metabolic rate when listening to conspecific when compared with heterospecific song. This early discrimination between songs probably leads to fewer heterospecific matings, and thus higher fitness of collared flycatchers living in sympatty with closely related species.

  • 36.
    Nordström, Karin
    et al.
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience.
    Bolzon, Douglas M.
    O'Carroll, David C.
    Spatial facilitation by a high-performance dragonfly target-detecting neuron2011In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 7, no 4, 588-592 p.Article in journal (Refereed)
    Abstract [en]

    Many animals visualize and track small moving targets at long distances-be they prey, approaching predators or conspecifics. Insects are an excellent model system for investigating the neural mechanisms that have evolved for this challenging task. Specialized small target motion detector (STMD) neurons in the optic lobes of the insect brain respond strongly even when the target size is below the resolution limit of the eye. Many STMDs also respond robustly to small targets against complex stationary or moving backgrounds. We hypothesized that this requires a complex mechanism to avoid breakthrough responses by background features, and yet to adequately amplify the weak signal of tiny targets. We compared responses of dragonfly STMD neurons to small targets that begin moving within the receptive field with responses to targets that approach the same location along longer trajectories. We find that responses along longer trajectories are strongly facilitated by a mechanism that builds up slowly over several hundred milliseconds. This allows the neurons to give sustained responses to continuous target motion, thus providing a possible explanation for their extraordinary sensitivity.

  • 37. Pitala, Natalia
    et al.
    Gustafsson, Lars
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Sendecka, Joanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Brommer, Jon E .
    Nestling immune response to phytohaemagglutinin is not heritable in collared flycatchers2007In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 3, no 4, 418-421 p.Article in journal (Refereed)
    Abstract [en]

    The response to intradermally injected phytohaemagglutinin (PHA-response) is a commonly used quantification of avian immunocompetence (the ability to resist pathogens). Parasite-mediated sexual selection requires heritable immunocompetence, but evidence for heritability of PHA-response in birds largely stems from full-sib comparisons. Using an animal model approach, we quantified the narrow-sense heritability of PHA-response in 1626 collared flycatcher (Ficedula albicollis) nestlings from 332 families, most of which were cross-fostered. Nestling PHA-response was not significantly heritable (h2=0.06±0.10), but was subject to non-heritable nest-of-origin effects (10% of variation). Our findings illustrate that full-sib comparisons of immunological measures may lead to an inflated estimate of heritability and also reveal a limited role of nestling PHA-response for sexual selection in this population.

  • 38.
    Recapet, Charlotte
    et al.
    Univ Lyon 1, CNRS, UMR 5558, Lab Biometrie & Biol Evolut, F-69622 Villeurbanne, France.;Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland..
    Daniel, Gregory
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ Lyon 1, CNRS, UMR 5558, Lab Biometrie & Biol Evolut, F-69622 Villeurbanne, France..
    Taroni, Joelle
    Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland..
    Bize, Pierre
    Univ Aberdeen, Inst Biol & Environm Sci, Aberdeen, Scotland..
    Doligez, Blandine
    Univ Lyon 1, CNRS, UMR 5558, Lab Biometrie & Biol Evolut, F-69622 Villeurbanne, France..
    Food supplementation mitigates dispersal-dependent differences in nest defence in a passerine bird2016In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 12, no 5, 20160097Article in journal (Refereed)
    Abstract [en]

    Dispersing and non-dispersing individuals often differ in phenotypic traits (e.g. physiology, behaviour), but to what extent these differences are fixed or driven by external conditions remains elusive. We experimentally tested whether differences in nest-defence behaviour between dispersing and non-dispersing individuals changed with local habitat quality in collared flycatchers, by providing additional food during the nestling rearing period. In control (non-food-supplemented) nests, dispersers were less prone to defend their brood compared with non-dispersers, whereas in food-supplemented nests, dispersing and non-dispersing individuals showed equally strong nest defence. We discuss the importance of dispersal costs versus adaptive flexibility in reproductive investment in shaping these differences in nest-defence behaviour between dispersing and non-dispersing individuals. Irrespective of the underlying mechanisms, our study emphasizes the importance of accounting for environmental effects when comparing traits between dispersing and non-dispersing individuals, and in turn assessing the costs and benefits of dispersal.

  • 39.
    Recapet, Charlotte
    et al.
    Univ Claude Bernard Lyon 1, Univ Lyon, Lab Biometrie & Biol Evolut, CNRS, Villeurbanne, France.;Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland..
    Sibeaux, Adelaide
    Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland..
    Cauchard, Laure
    Univ Montreal, Dept Sci Biol, Montreal, PQ, Canada..
    Doligez, Blandine
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology. Univ Claude Bernard Lyon 1, Univ Lyon, Lab Biometrie & Biol Evolut, CNRS, Villeurbanne, France.
    Bize, Pierre
    Univ Lausanne, Dept Ecol & Evolut, Lausanne, Switzerland.;Univ Aberdeen, Inst Biol & Environm Sci, Aberdeen, Scotland..
    Selective disappearance of individuals with high levels of glycated haemoglobin in a free-living bird2016In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 12, no 8, 20160243Article in journal (Refereed)
    Abstract [en]

    Although disruption of glucose homeostasis is a hallmark of ageing in humans and laboratory model organisms, we have little information on the importance of this process in free-living animals. Poor control of blood glucose levels leads to irreversible protein glycation. Hence, levels of protein glycation are hypothesized to increase with age and to be associated with a decline in survival. We tested these predictions by measuring blood glycated haemoglobin in 274 adult collared flycatchers of known age and estimating individual probability of recapture in the following 2 years. Results show a strong decrease in glycated haemoglobin from age 1 to 5 years and an increase thereafter. Individuals with high levels of glycated haemoglobin had a lower probability of recapture, even after controlling for effects of age and dispersal. Altogether, our findings suggest that poor control of glucose homoeostasis is associated with lower survival in this free-living bird population, and that the selective disappearance of individuals with the highest glycation levels could account for the counterintuitive age-related decline in glycated haemoglobin in the early age categories.

  • 40. Senar, Juan Carlos
    et al.
    Borras, Antoni
    Cabrera, Josep
    Cabrera, Ton
    Björklund, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Local differentiation in the presence of gene flow in the citril finch Serinus citrinella2006In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 2, no 1, 85-87 p.Article in journal (Refereed)
    Abstract [en]

    It is well known theoretically that gene flow can impede genetic differentiation between populations. In this study, we show that in a highly mobile bird species, where dispersal is well documented, there is a strong genetic and morphological differentiation over a very short geographical scale (less than 5 km). Allocation tests revealed that birds caught in one area were assigned genetically to the same area with a very high probability, in spite of current gene flow. Populations were also morphologically differentiated. The results suggest that the relationship between gene flow and differentiation can be rather complicated and non-intuitive.

  • 41.
    Skovsted, Christian B.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Brock, Glenn A.
    Lindström, Anna
    Peel, John S.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Uppsala University, Museums etc., Museum of Evolution.
    Paterson, John R.
    Fuller, Margaret K.
    Early Cambrian record of failed durophagy and shell repair in an epibenthic mollusc2007In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 3, no 3, 314-317 p.Article in journal (Refereed)
    Abstract [en]

    Predation is arguably one of the main driving forces of early metazoan evolution, yet the fossil record of predation during the Ediacaran–Early Cambrian transition is relatively poor. Here, we present direct evidence of failed durophagous (shell-breaking) predation and subsequent shell repair in the Early Cambrian (Botoman) epibenthic mollusc Marocella from the Mernmerna Formation and Oraparinna Shale in the Flinders Ranges, South Australia. This record pushes back the first appearance of durophagy on molluscs by approximately 40 Myr.

  • 42.
    Svensson, Emma
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Götherström, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Temporal fluctuations of Y-chromosomal variation in Bos taurus2008In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 4, no 6, 752-754 p.Article in journal (Refereed)
    Abstract [en]

    Phylogeography has recently become more abundant in studies of demographic history of both wild and domestic species. A single nucleotide polymorphism (SNP) in the intron of the Y-chromosomal gene UTY19 displays a north south gradient in modern cattle. Support for this geographical distribution of haplogroups has previously also been seen in ancient cattle from Germany. However, when analysing 38 historic remains of domestic bulls and three aurochs from northern Europe for this SNP we found no such association. Instead, we noted extensive amounts of temporal variation that can be attributed to transportation of cattle and late breed formation.

  • 43.
    Tsuboi, Masahito
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Gonzalez-Voyer, Alejandro
    Kolm, Niclas
    Functional coupling constrains craniofacial diversification in Lake Tanganyika cichlids2015In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 11, no 5, 20141053Article in journal (Refereed)
    Abstract [en]

    Functional coupling, where a singlemorphological trait performs multiple functions, is a universal feature of organismal design. Theory suggests that functional coupling may constrain the rate of phenotypic evolution, yet empirical tests of this hypothesis are rare. In fish, the evolutionary transition from guarding the eggs on a sandy/rocky substrate (i.e. substrate guarding) to mouthbrooding introduces a novel function to the craniofacial system and offers an ideal opportunity to test the functional coupling hypothesis. Using a combination of geometric morphometrics and a recently developed phylogenetic comparative method, we found that head morphology evolution was 43% faster in substrate guarding species than in mouthbrooding species. Furthermore, for species in which females were solely responsible for mouthbrooding the males had a higher rate of head morphology evolution than in those with biparental mouthbrooding. Our results support the hypothesis that adaptations resulting in functional coupling constrain phenotypic evolution.

  • 44. Valdiosera, Cristina
    et al.
    Garcia, Nuria
    Dalén, Love
    Smith, Colin
    Kahlke, Ralf-Dietrich
    Lidén, Kerstin
    Angerbjörn, Anders
    Arsuaga, Juan Luis
    Götherström, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Typing single polymorphic nucleotides in mitochondrial DNA as a way to access Middle Pleistocene DNA2006In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 2, no 4, 601-603 p.Article in journal (Refereed)
    Abstract [en]

    In this study, we have used a technique designed to target short fragments containing informative mitochondrial substitutions to extend the temporal limits of DNA recovery and study the molecular phylogeny of Ursus deningeri. We present a cladistic analysis using DNA recovered from 400 kyr old U. deningeri remains, which demonstrates U. deningeri's relation to Ursus spelaeus. This study extends the limits of recovery from skeletal remains by almost 300 kyr. Plant material from permafrost environments has yielded DNA of this age in earlier studies, and our data suggest that DNA in teeth from cave environments may be equally well preserved.

  • 45.
    Wheatcroft, David
    et al.
    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.
    A blueprint for vocal learning: auditory predispositions from brains genomes2015In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 11, no 8, 20150155Article, review/survey (Refereed)
    Abstract [en]

    Memorizing and producing complex strings of sound are requirements for spoken human language. We share these behaviours with likely more than 4000 species of songbirds, making birds our primary model for studying the cognitive basis of vocal learning and, more generally, an important model for how memories are encoded in the brain. In songbirds, as in humans, the sounds that a juvenile learns later in life depend on auditory memories formed early in development. Experiments on a wide variety of songbird specie's suggest that the formation and lability of these auditory memories, in turn, depend on auditory predispositions that stimulate learning when a juvenile hears relevant, species-typical sounds. We review evidence that variation in key features of these auditory predispositions are determined by variation in genes underlying the development of the auditory system. We argue that increased investigation of the neuronal basis of auditory predispositions expressed early in life in conibination with modem comparative genomic approaches may provide insights into the evolution of vocal learning.

  • 46.
    Ålund, Murielle
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Immler, Simone
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    Rice, Amber M.
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Low fertility of wild hybrid male flycatchers despite recent divergence2013In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 9, no 3, 20130169Article in journal (Refereed)
    Abstract [en]

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

  • 47.
    Ödeen, Anders
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Håstad, Olle
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Physiology and Developmental Biology, Evolutionary Organism Biology.
    Alström, Per
    Department of Vertebrate Zoology, Swedish Museum of Natural History.
    Evolution of ultraviolet vision in shorebirds (Charadriiformes)2010In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 6, no 3, 370-374 p.Article in journal (Refereed)
    Abstract [en]

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

1 - 47 of 47
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf