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  • 1.
    Abbott, Jessica K.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Svensson, Erik I.
    Lund University.
    Morph-specific variation in intersexual genetic correlations in an intra-specific mimicry system2010In: Evolutionary Ecology Research, ISSN 1522-0613, E-ISSN 1937-3791, Vol. 12, no 1, p. 105-118Article in journal (Refereed)
    Abstract [en]

    Background: Positive intersexual genetic correlations are typically viewed as constraining the evolution of sexual dimorphism, when traits are subject to sexually antagonistic selection. Our study species, the damselfly Ischnura elegans, has a female-limited colour polymorphism with three female colour morphs (males are monomorphic), one of which is considered a male mimic.

    Question: Are there morph-specific differences in the magnitude of intersexual genetic correlations in I. elegans? Specifically, do male-mimic (Androchrome) females have higher intersexual genetic correlations for morphological traits than non-mimic (Infuscans) females?

    Methods: We collected copulating pairs in the field and raised offspring from these pairs in the laboratory. We measured five morphological traits in both parent and offspring generations and investigated their heritabilities and genetic correlations.

    Results: We found a negative overall relationship between the degree of sexual dimorphism for a trait and its intersexual genetic correlation. But the magnitude and direction of intersexual genetic correlations depended on the female morph. As expected, male mimic (Androchrome) females had higher intersexual genetic correlations. In addition, the genetic correlations between the morphs were in all cases significantly lower than unity. Male mimic (Androchrome) females had higher mother-son covariances than the non-mimic (Infuscans) morph, and this difference is the proximate explanation for the difference in intersexual genetic correlations between the morphs.

  • 2. Ah-King, Malin
    et al.
    Elofsson, Helena
    Kvarnemo, Charlotta
    Rosenqvist, Gunilla
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Why is there no sperm competition in a pipefish with externally brooding males? Insights from sperm activitation and morphology2006In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 68, no 3, p. 958-962Article in journal (Refereed)
    Abstract [en]

    Nerophis ophidion sperm activation and morphology were investigated with the aim of explaining the apparent lack of sperm competition in this syngnathid with externally brooding males. Nerophis ophidion sperm were activated by a mixture of ovarian fluid and sea water, but not by sea water alone. This indicated that sperm were not shed into the water but needed to be released near the eggs, which probably restrained sperm competition.

  • 3.
    Ahnesjö, Ingrid
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Behavioural temperature preference in a brooding male pipefish Syngnathus typhle2008In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 73, no 4, p. 1039-1045Article in journal (Refereed)
    Abstract [en]

    In the broad-nosed pipefish Syngnathus typhle, brooding males positioned themselves significantly more often towards the warmer part (18 degrees C) of an aquarium. whereas females were indifferent in this respect. This behavioural temperature preference may increase male brooding rate and indirectly influence patterns of mating competition. (c) 2008 The Author Journal compilation (c) 2008 The Fisheries Society of the British Isles.

  • 4. Aho, T
    et al.
    Rönn, J
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Piironen, J
    Björklund, M
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    Impacts of effective population size on genetic diversity and relatedness in hatchery reared Brown trout (Salmo trutta L.)2006In: Aquaculture, Vol. 253, p. 244-248Article in journal (Refereed)
  • 5.
    Alatalo, Rauno V
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Lundberg, Arne
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Sundberg, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Can Female Preference Explain Sexual Dichromatism In The Pied Flycatcher, Ficedula-Hypoleuca1990In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 39, p. 244-252Article in journal (Refereed)
    Abstract [en]

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

  • 6.
    Allander, Klas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Sundberg, Jan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Temporal variation and reliability of blood parasite levels in captive Yellowhammer males Emberiza citrinella1997In: Journal of Avian Biology, ISSN 0908-8857, E-ISSN 1600-048X, Vol. 28, no 4, p. 325-330Article in journal (Refereed)
    Abstract [en]

    The temporal variation of blood parasites in captive Yellowhammer males was studied in order to investigate possible costs of parasites. Birds were caught in the wild in early April and kept in aviaries during the study period. Blood samples were taken, body mass measured, and moult was scored twelve times for the same individuals from April to October. Blood parasites were detectable in smears during the whole study period with an intensity peak coinciding with breeding in the wild. Young birds had more parasites and a consistently higher body mass than older birds. There was no relationship between parasite intensity and mass in older birds but possibly one in young birds. Parasites did not seem to affect moult in either age class. Repeatability of parasite counts of smears from the same individual was very high and smears are therefore a reliable method for estimating parasite intensity. We conclude that blood parasites are probably most severe during, but occur in their hosts long after, the breeding season. Possible costs of parasites outside the breeding season require further study.

  • 7. Andersson, MS
    et al.
    Ödeen, A
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    Håstad, O
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    A partly covered badge signalling avian virus resistance2006In: Acta Zoologica, Vol. 87, p. 71-76Article in journal (Refereed)
  • 8.
    Andersson, Måns Sverker
    Uppsala University, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Faculty of Arts, Centre for Gender Research. Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Genusperspektiv på beteendens evolutionära genetik2006In: Dialoger mellan kön och genus, 2006Chapter in book (Other (popular scientific, debate etc.))
    Abstract [en]

    Psykologen Virginia Valian talar om traditionell kategorisering baserad på kön (gender schemas). Man har med experiment tydligt kunnat visa att sådana kategoriseringar påverkar vår perception radikalt. Studier visar till exempel att försöks¬personer som ställs inför uppgiften att uppskatta mäns och kvinnors längd regelmässigt underskattar kvinnors längd. Föga förvånande så bär vi med oss dessa könskategorier även när vi studerar djur och evolution.

    Den ornitologiskt kunnige som slår upp sparvhök i Bonniers Alla Europas fåglar i färg slås av att honan avbildas som likstor med hanen trots att honorna i verkligheten är mycket större. Tvärtemot vad fågelboken antyder så är det lättare att missta en sparvhökshona för hanen hos den större duvhöken, än för hanen av den egna arten. Det här är en typ av reproduktion av könsstereotyp och missvisande information som är vanlig i den ornitologiska litteraturen.

    Ornitologin i sin tur är intimt kopplad till och uppvisar strukturella likheter med den del av evolutionsbiologin som får allt större inflytande på vår förståelse av beteenden, beteendeekologin.

    Beteendeekologiska teorier och resultat kan innebära en revolution för tänkandet kring kön och könsbundna egenskaper. Att plocka isär och återuppbygga könsbegreppen har delvis varit nödvändigt, i synnerhet för de som studerar vad vi kallar ”sexuell selektion”. Därför har genusperspektiven stora möjligheter att kunna bidra med insikter viktiga för både teoribildningen och det praktiska vetenskapliga hantverket.

  • 9.
    Andersson, Måns Sverker
    et al.
    Uppsala University, Humanistisk-samhällsvetenskapliga vetenskapsområdet, Faculty of Arts, Centre for Gender Research. Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Eliasson, Miriam
    Karolinska Institutet.
    Hur görs djur?: Könsstereotyper och androcentrism i studier av andra arter än Homo sapiens.2006In: Kvinovetenskaplig Tidskrift, no 2-3, p. 65-76Article in journal (Refereed)
    Abstract [en]

    The field of evolutionary ecology in general and behavioural ecology in particular is often regarded as an androcentric science where sexual stereotypes pervade. In this article we review some of the evidence for this notion and suggest that behavioural ecology still is suffering from such gender bias. The criticism so far has mainly been centred on how these problems affect the understanding of humans. Here focus on how it can produce misconceptions of animals and animal behaviour. In particular we discuss why gender perspectives are relevant to theory production, experiment design and the choice of study species. We also suggest that sexual stereotypes and androcentrism are not a necessary part of behavioural ecology, and that the field has the potential of producing knowledge that could revolutionize some of the thinking around sex and gender.

  • 10.
    Andersson, Måns Sverker
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology. zooekologi.
    Gustafsson, Lars
    Glycosylated haemoglobin: a new measure of condition in birds1995In: Proceedings of the Royal Society of London, no 260, p. 299-303Article in journal (Refereed)
    Abstract [en]

    Abstract: The influence of condition on time of breeding and reproductive success has been discussed since Darwin first suggested a relation in 1871. We used a novel method to investigate the influence of condition on the timing of breeding and reproductive success by measuring a relatively inert physiological parameter - the amount of glycosylated haemoglobin - in blood samples taken from the collared flycatcher Ficedula albicollis. The percentage of glycosylated haemoglobin (%HbG) was assumed to be proportional to the average blood glucose level, during the 3-5 weeks before the blood sampling. The %HbG was influenced neither by sex nor age. Date of arrival at the breeding ground was negatively correlated with %HbG so that early-arriving birds had significantly higher %HbG than those arriving later. Clutch size, corrected for the effect of laying date, correlated positively with %HbG in females, as did the number of fledged young, corrected for the effect of laying date, for both sexes. We found no correlation between body mass and the %HbG. We suggest that prebreeding condition influences the timing of breeding and subsequent reproductive performance and that %HbG can be used as an indicator of prebreeding-condition in migrating birds.

  • 11. Andres, JA
    et al.
    Morrow, EH
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Evolutionary Biology. Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    The origin of interlocus sexual conflict: is sex-linkage important2003In: Journal of Evolutionary Biology, Vol. 16, p. 219-223Article in journal (Refereed)
  • 12.
    Andres JA, Morrow EH
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Evolutionary Biology. Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    The origin of interlocus sexual conflict: is sex-linkage important?2003In: Journal of Evolutionary Biology, Vol. 16, p. 219-223Article in journal (Refereed)
  • 13.
    Arnqvist, G
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    Sensory exploiation and sexual conflict2006In: Philosophical Transactions of the Royal Society B, Vol. 361, p. 375-386Article in journal (Refereed)
  • 14.
    Arnqvist, Göran
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    Sexual conflict and sexual selection: lost in the chase2004In: Evolution, Vol. 58, no 6, p. 1383-1388Article in journal (Refereed)
  • 15.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Dowling, Damian K.
    Eady, Paul
    Gay, Laurene
    Tregenza, Tom
    Tuda, Midori
    Hosken, David J.
    Genetic architecture of metabolic rate: environment specific epistasis between mitochondrial and nuclear genes in an insect2010In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 64, no 12, p. 3354-3363Article in journal (Refereed)
    Abstract [en]

    The extent to which mitochondrial DNA (mtDNA) variation is involved in adaptive evolutionary change is currently being reevaluated. In particular, emerging evidence suggests that mtDNA genes coevolve with the nuclear genes with which they interact to form the energy producing enzyme complexes in the mitochondria. This suggests that intergenomic epistasis between mitochondrial and nuclear genes may affect whole-organism metabolic phenotypes. Here, we use crossed combinations of mitochondrial and nuclear lineages of the seed beetle Callosobruchus maculatus and assay metabolic rate under two different temperature regimes. Metabolic rate was affected by an interaction between the mitochondrial and nuclear lineages and the temperature regime. Sequence data suggests that mitochondrial genetic variation has a role in determining the outcome of this interaction. Our genetic dissection of metabolic rate reveals a high level of complexity, encompassing genetic interactions over two genomes, and genotype x genotype x environment interactions. The evolutionary implications of these results are twofold. First, because metabolic rate is at the root of life histories, our results provide insights into the complexity of life-history evolution in general, and thermal adaptation in particular. Second, our results suggest a mechanism that could contribute to the maintenance of nonneutral mtDNA polymorphism.

  • 16.
    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, p. 491-493Article 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.

  • 17.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Jones, Therésa M.
    Elgar, Mark A.
    The extraordinary mating system of Zeus bugs (Heteroptera: Veliidae: Phoreticovelia sp)2007In: Australian journal of zoology (Print), ISSN 0004-959X, E-ISSN 1446-5698, Vol. 55, no 2, p. 131-137Article in journal (Refereed)
    Abstract [en]

    Wingless female Zeus bugs (genus: Phoreticovelia) produce a secretion from dorsal glands that males feed upon when riding on females. This unique form of sex-role-reversed nuptial feeding may have set the stage for an unusual mating system. Here, we provide natural history details of the mating behaviour for two Zeus bug species. While these species have many mating behaviours in common, the wing morphs within species exhibit entirely different mating strategies. Adult wingless females are ridden permanently by adult wingless males. In the wild, adult sex-ratios among the wingless morph are male-biased; few unmounted adult females exist and many males instead ride immature females who also produce glandular secretions. In contrast, sex-ratios among the winged morph is not male-biased, sexual size dimorphism is less pronounced, females have no dorsal glands and are, consequently, not ridden by males. Field and laboratory observations show that mating is strongly assortative by wing morph. This assortment may allow evolutionary divergence between the two morphs. We discuss the implications of this mating system and suggest that it adds to those studies showing that sexually antagonistic coevolution can be a driver of mating system evolution.

  • 18.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Kirkpatrick, M.
    The Evolution of Infidelity in Socially Monogamous Passerines Revisited: A Reply to Griffith2007In: American Naturalist, ISSN 0003-0147, E-ISSN 1537-5323, Vol. 169, no 2, p. 282-283Article in journal (Refereed)
  • 19.
    Arnqvist, Göran
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    Kirkpatrick, Mark
    The evolution of infidelity in socially monogamous passerines: the strength of direct and indirect selection on extrapair copulation behavior in females2005In: American Naturalist, Vol. 165, p. S26-S37Article in journal (Refereed)
  • 20.
    Arnqvist, Göran
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Nilsson, Tina
    Katvala, Mari
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Mating rate and fitness in femal bean weevils2005In: Behavioral Ecology, Vol. 16, p. 123-127Article in journal (Refereed)
  • 21.
    Arnqvist, Göran
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    Rowe, Locke
    Sexual Conflict2005Book (Refereed)
  • 22.
    Arnqvist, Göran
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Tuda, Midori
    Sexual conflict and the gender load: correlated evolution between population fitness and sexual dimorphism in seed beetles2010In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 277, no 1686, p. 1345-1352Article in journal (Refereed)
    Abstract [en]

    Although males and females share much of the same genome, selection is often distinct in the two sexes. Sexually antagonistic loci will in theory cause a gender load in populations, because sex-specific selection on a given trait in one sex will compromise the adaptive evolution of the same trait in the other sex. However, it is currently not clear whether such intralocus sexual conflict (ISC) represents a transient evolutionary state, where conflict is rapidly resolved by the evolution of sexual dimorphism (SD), or whether it is a more chronic impediment to adaptation. All else being equal, ISC should manifest itself as correlated evolution between population fitness and SD in traits expressed in both sexes. However, comparative tests of this prediction are problematic and have been unfeasible. Here, we assess the effects of ISC by comparing fitness and SD across distinct laboratory populations of seed beetles that should be well adapted to a shared environment. We show that SD in juvenile development time, a key life-history trait with a history of sexually antagonistic selection in this model system, is positively related to fitness. This effect is due to a correlated evolution between population fitness and development time that is positive in females but negative in males. Loosening the genetic bind between the sexes has evidently allowed the sexes to approach their distinct adaptive peaks.

  • 23.
    Arrendal, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Conservation Genetics of the Eurasian Otter in Sweden2007Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, molecular genetic methods were used to study a threatened species, the Eurasian otter. Estimates of population size and population dynamics parameters were obtained, the genetic effects of a restocking program was evaluated, and a population viability analysis was conducted to assess which demographic parameters are most important for the future viability of an otter population. Many of the studies were based on noninvasive genetic sampling of faeces.

    In the genetic evaluation of the restocking program, it was found that the released otters had contributed to subsequent generations. However, the effects were to a large degree limited to the near surroundings of the release areas.

    Comparison of two census methods, snow-tracking and noninvasive genetic census based on faeces, showed that approximately only half of the otters detected with the genetic census were found with the snow-tracking census. It is recommended to combine these two methods to obtain the most reliable estimates of population size.

    A short-term study on population dynamics in otters showed that apparent survival was higher in females than in males and that the rate of addition was also high and likely influenced by migration.

    The population viability analysis incorporated both genetics and demography and revealed that survival to first reproduction was the most crucial demographic parameter affecting the viability of the study population. This result suggests that conservation efforts should be focused on protocols that enhance the survival prospects of young females. Environmental stochasticity was also found to have large effects on the probability of extinction of this population.

    List of papers
    1. Genetic evaluation of an otter translocation program
    Open this publication in new window or tab >>Genetic evaluation of an otter translocation program
    Show others...
    2004 (English)In: Conservation Genetics, ISSN 1566-0621 (Print) 1572-9737 (Online), Vol. 5, no 1, p. 79-88Article in journal (Refereed) Published
    Identifiers
    urn:nbn:se:uu:diva-95530 (URN)
    Available from: 2007-03-02 Created: 2007-03-02 Last updated: 2009-03-31Bibliographically approved
    2. The evolution of a restocked otter population in Sweden
    Open this publication in new window or tab >>The evolution of a restocked otter population in Sweden
    (English)Manuscript (Other (popular science, discussion, etc.))
    Identifiers
    urn:nbn:se:uu:diva-95531 (URN)
    Available from: 2007-03-02 Created: 2007-03-02 Last updated: 2010-01-14Bibliographically approved
    3. Reliability of noninvasive genetic census of otters compared to field censuses
    Open this publication in new window or tab >>Reliability of noninvasive genetic census of otters compared to field censuses
    2007 (English)In: Conservation Genetics, ISSN 1566-0621, E-ISSN 1572-9737, Vol. 8, no 5, p. 1097-1107Article in journal (Refereed) Published
    Abstract [en]

    Conservation and management actions are often highly dependent on accurate estimations of population sizes. However, these estimates are difficult to obtain for elusive and rare species. We compared two census methods for Eurasian otter: snow tracking and noninvasive genetic census based on the genotyping of faecal samples. With the noninvasive genetic census we detected the presence of almost twice as many otters as with snow tracking (23 and 10–15, respectively), and mark-recapture estimates based on the genetic census indicated that the real number of otters could be even higher. Our results indicate that snow tracking tends to underestimate the number of individuals and also that it is more susceptible to subjective assessment. We compared the strengths and weaknesses of the two methods.

    Keywords
    Individual identification, Faeces, Monitoring, Population size, Snow tracking
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:uu:diva-95532 (URN)10.1007/s10592-006-9266-y (DOI)000248850700009 ()
    Available from: 2007-03-02 Created: 2007-03-02 Last updated: 2017-12-14Bibliographically approved
    4. Population dynamics parameters obtained by noninvasive genetic methods in a Eurasian otter population
    Open this publication in new window or tab >>Population dynamics parameters obtained by noninvasive genetic methods in a Eurasian otter population
    (English)Manuscript (Other (popular science, discussion, etc.))
    Identifiers
    urn:nbn:se:uu:diva-95533 (URN)
    Available from: 2007-03-02 Created: 2007-03-02 Last updated: 2010-01-14Bibliographically approved
    5. A demo-genetic analysis of a recovering population of otters in central Sweden
    Open this publication in new window or tab >>A demo-genetic analysis of a recovering population of otters in central Sweden
    2008 (English)In: Animal Conservation, ISSN 1367-9430, E-ISSN 1469-1795, Vol. 11, no 6, p. 529-534Article in journal (Refereed) Published
    Abstract [en]

    We performed a demo-genetic population viability analysis on a recovering population of otters Lutra lutra in Central Sweden, using data on population size, survival and genetic data from microsatellites. Population data were obtained from genotyping faeces. At present, the size and genetic variability of the population is increasing. We found that survival to first reproduction was the most crucial demographic parameter, and that even slight changes downward in this parameter, might lead to a declining population trajectory. Human factors that can affect mortality are traffic, fishing equipment and traps, and we argue that efforts to minimize road kills by means of safe passages as well as careful fishing efforts in streams and lakes would reduce the risk of extinction. In general, even though the population is now growing and has no inbreeding problem, its small  abundance could make it vulnerable to chance events and environmental perturbations.

    Keywords
    otter, PVA, genetics, demographic stochasticity, extinction
    National Category
    Biological Sciences
    Identifiers
    urn:nbn:se:uu:diva-95534 (URN)10.1111/j.1469-1795.2008.00214.x (DOI)000261780600012 ()
    Available from: 2007-03-02 Created: 2007-03-02 Last updated: 2017-12-14Bibliographically approved
  • 24.
    Arrendal, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Population dynamics parameters obtained by noninvasive genetic methods in a Eurasian otter populationManuscript (Other (popular science, discussion, etc.))
  • 25.
    Arrendal, Johanna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Laikre, Linda
    Mortensen, Peter
    Sjöåsen, Thomas
    The evolution of a restocked otter population in SwedenManuscript (Other (popular science, discussion, etc.))
  • 26.
    Arrendal, Johanna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Vilà, Carles
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Björklund, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Reliability of noninvasive genetic census of otters compared to field censuses2007In: Conservation Genetics, ISSN 1566-0621, E-ISSN 1572-9737, Vol. 8, no 5, p. 1097-1107Article in journal (Refereed)
    Abstract [en]

    Conservation and management actions are often highly dependent on accurate estimations of population sizes. However, these estimates are difficult to obtain for elusive and rare species. We compared two census methods for Eurasian otter: snow tracking and noninvasive genetic census based on the genotyping of faecal samples. With the noninvasive genetic census we detected the presence of almost twice as many otters as with snow tracking (23 and 10–15, respectively), and mark-recapture estimates based on the genetic census indicated that the real number of otters could be even higher. Our results indicate that snow tracking tends to underestimate the number of individuals and also that it is more susceptible to subjective assessment. We compared the strengths and weaknesses of the two methods.

  • 27.
    Arrendal, Johanna
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology. Zooekologi.
    Walker, CF
    Sundqvist, AK
    Hellborg, L
    Vila, Carles
    Department of Evolution, Genomics and Systematics. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Genetic evaluation of an otter transocation program2004In: Conservation Genetics, Vol. 5, p. 79-88Article in journal (Refereed)
  • 28.
    Arrendal, Johanna
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Walker, Christopher
    Sundqvist, Anna-Karin
    Hellborg, Linda
    Vilà, Carles
    Genetic evaluation of an otter translocation program2004In: Conservation Genetics, ISSN 1566-0621 (Print) 1572-9737 (Online), Vol. 5, no 1, p. 79-88Article in journal (Refereed)
  • 29.
    Backström, Niclas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Brandström, Mikael
    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 Ecology and Evolution, Animal Ecology.
    Qvarnström, Anna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Cheng, Hans
    Ellegren, Hans
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolution, Genomics and Systematics, Evolutionary Biology.
    Genetic mapping in a natural population of collared flycatchers (Ficedula albicollis): Conserved synteny but gene order rearrangements on the avian Z chromosome2006In: Genetics, ISSN 0016-6731, E-ISSN 1943-2631, Vol. 174, no 1, p. 377-386Article in journal (Refereed)
    Abstract [en]

    Data from completely sequenced genomes are likely to open the way for novel studies of the genetics of nonmodel organisms, in particular when it comes to the identification and analysis of genes responsible for traits that are under selection in natural populations. Here we use the draft sequence of the chicken genome as a starting point for linkage mapping in a wild bird species, the collared flycatcher-one of the most well-studied avian species in ecological and evolutionary research. A pedigree of 365 flycatchers was established and genotyped for single nucleotide polymorphisms in 23 genes selected from (and spread over most of) the chicken Z chromosome. All genes were also found to be located on the Z chromosome in the collared flycatcher, confirming conserved synteny at the level of gene content across distantly related avian lineages. This high degree of conservation mimics the situation seen for the mammalian X chromosome and may thus be a general feature in sex chromosome evolution, irrespective of whether there is male or female heterogamety. Alternatively, such unprecedented chromosomal conservation may be characteristic of most chromosomes in avian genome evolution. However, several internal rearrangements were observed, meaning that the transfer of map information from chicken to nonmodel bird species cannot always assume conserved gene orders. Interestingly, the rate of recombination on the Z chromosome of collared flycatchers was only similar to 50% that of chicken, challenging the widely held view that birds generally have high recombination rates.

  • 30.
    Bailey, Richard
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Schonrogge, Karsten
    Cook, M
    Melika, George
    Csoka, Gyoergy
    Thuroczy, Csaba
    Stone, Graham N.
    Host Niches and Defensive Extended Phenotypes Structure Parasitoid Wasp Communities2009In: PLoS biology, ISSN 1544-9173, E-ISSN 1545-7885, Vol. 7, no 8, p. e1000179-Article in journal (Refereed)
    Abstract [en]

    Oak galls are spectacular extended phenotypes of gallwasp genes in host oak tissues and have evolved complex morphologies that serve, in part, to exclude parasitoid natural enemies. Parasitoids and their insect herbivore hosts have coevolved to produce diverse communities comprising about a third of all animal species. The factors structuring these communities, however, remain poorly understood. An emerging theme in community ecology is the need to consider the effects of host traits, shaped by both natural selection and phylogenetic history, on associated communities of natural enemies. Here we examine the impact of host traits and phylogenetic relatedness on 48 ecologically closed and species-rich communities of parasitoids attacking gall-inducing wasps on oaks. Gallwasps induce the development of spectacular and structurally complex galls whose species- and generation-specific morphologies are the extended phenotypes of gallwasp genes. All the associated natural enemies attack their concealed hosts through gall tissues, and several structural gall traits have been shown to enhance defence against parasitoid attack. Here we explore the significance of these and other host traits in predicting variation in parasitoid community structure across gallwasp species. In particular, we test the "Enemy Hypothesis,'' which predicts that galls with similar morphology will exclude similar sets of parasitoids and therefore have similar parasitoid communities. Having controlled for phylogenetic patterning in host traits and communities, we found significant correlations between parasitoid community structure and several gall structural traits (toughness, hairiness, stickiness), supporting the Enemy Hypothesis. Parasitoid community structure was also consistently predicted by components of the hosts' spatiotemporal niche, particularly host oak taxonomy and gall location (e.g., leaf versus bud versus seed). The combined explanatory power of structural and spatiotemporal traits on community structure can be high, reaching 62% in one analysis. The observed patterns derive mainly from partial niche specialisation of highly generalist parasitoids with broad host ranges (>20 hosts), rather than strict separation of enemies with narrower host ranges, and so may contribute to maintenance of the richness of generalist parasitoids in gallwasp communities. Though evolutionary escape from parasitoids might most effectively be achieved via changes in host oak taxon, extreme conservatism in this trait for gallwasps suggests that selection is more likely to have acted on gall morphology and location. Any escape from parasitoids associated with evolutionary shifts in these traits has probably only been transient, however, due to subsequent recruitment of parasitoid species already attacking other host galls with similar trait combinations.

  • 31.
    Bergek, Sara
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Population divergence at small spatial scales: – theoretical and empirical investigations in perch2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Genetically structured populations arise when gene flow between groups of individuals is hindered by geographical, behavioural or temporal barriers. The identification of such groups is important for understanding evolution and has large implications for conservation concern. The field of population subdivision has received a lot of interest throughout the years and gained empirical support from a number of species. However, very little is known about population structure at small spatial scales, especially in a highly mobile species such as fish. The main object for my thesis was to further investigate population differentiation, explicitly at small spatial scales in the Eurasian perch. My results show that in this species, genetic differentiation occurs, even at very small spatial scales, both within lakes and in the Baltic Sea. Additionally, the differentiation can be stable over years and thus have a large impact in the evolution of adaptation to different environments. I also found barriers to gene flow that overlapped with the largest change in spring temperature, suggesting a temporal difference in spawning. Morphological differences were found at these small scales as well which indicates that a difference in food resources might be an underlying cause of change. My thesis work shows that the aquatic environment might not be as homogenous as widely thought and that there could be barriers or adaptations to different environments that hinder the fish from genetic panmixia. Slight patterns of isolation by distance (IBD) were found in the Baltic Sea, implying that the distance (i.e. currents) effect the level of differentiation via drifting of larvae and/or small fish. However, I have also theoretically investigated the IBD model of and seen that it is no longer correct when differences in population sizes are introduced. The pattern of IBD can mean high levels of gene flow or no gene flow at all, solely dependent on population size differences and fluctuations. My thesis has resulted in new and important findings regarding the existence and cause of genetic differentiation at very small spatial scales and thus added new knowledge into the field of evolution and speciation. In addition, my results also give insights into the contemporary state of the Eurasian perch and future evolutionary potential.

    List of papers
    1. Cryptic barriers to dispersal within a lake allow genetic differentiation of Eurasian perch
    Open this publication in new window or tab >>Cryptic barriers to dispersal within a lake allow genetic differentiation of Eurasian perch
    2007 (English)In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 61, no 8, p. 2035-2041Article in journal (Refereed) Published
    Abstract [en]

    Gene flow between coexisting or nearby populations normally prevents genetic divergence and local adaptation. Despite this, there are an increasing number of reports of sympatric sister taxa, indicating potential divergence and speciation in the face of gene flow. A large number of such reported cases involve lake-dwelling fish, which are expected to run into few physical barriers to dispersal within their aquatic habitat. However, such cases may not necessarily reflect sympatric speciation if cryptic dispersal barriers are common in lakes and other aquatic systems. In this study, we examined genetic differentiation in perch (Perca fluviatilis L.) from nine locations in a single, small lake (24 km(2)), using microsatellites. We detected significant genetic differentiation in all but two pairwise comparisons. These patterns were not consistent with divergence by distance or the existence of kin groups. Instead, they suggest that cryptic barriers to dispersal exist within the lake, allowing small-scale genetic divergence. Such an observation suggests that allopatric (or parapatric) divergence may be possible, even in small, apparently homogenous environments such as lakes. This has important consequences for how we currently view evidence from nature for sympatric speciation.

    Place, publisher, year, edition, pages
    Oxford: Wiley-Blackwell, 2007
    Keywords
    Allopatric speciation, Geographic reproductive barriers, Microsatellites, Perca fluviatilis L., Small-scale genetic divergence, sympatric speciation
    National Category
    Biological Sciences
    Research subject
    Animal Ecology
    Identifiers
    urn:nbn:se:uu:diva-107227 (URN)10.1111/j.1558-5646.2007.00163.x (DOI)000248600300022 ()
    Available from: 2009-07-30 Created: 2009-07-30 Last updated: 2017-12-13Bibliographically approved
    2. Spatiotemporal analysis shows stable genetic differentiation and barriers to dispersal in the Eurasian perch (Perca fluviatilis L.)
    Open this publication in new window or tab >>Spatiotemporal analysis shows stable genetic differentiation and barriers to dispersal in the Eurasian perch (Perca fluviatilis L.)
    2009 (English)In: Evolutionary Ecology Research, ISSN 1522-0613, E-ISSN 1937-3791, Vol. 11, no 5, p. 827-840Article in journal (Refereed) Published
    Abstract [en]

    Background: Recently, unexpected or cryptic barriers to gene flow causing genetic discontinuities have been found in a number of animal taxa, even in apparently highly connected areas such as aquatic environments. 

    Goal: Investigate the temporal stability of previously documented microgeographic genetic structure in a fish.

    Organism: Eurasian perch (Perca fluviatilis L.)

    Method: We sampled four locations over a period of 2 years. We used six microsatellites to investigate population differentiation. We compared within-year to between-year differentiation.

    Results: The significant genetic differentiation found between locations in 2004 was still present in 2006. The strongest barriers to gene flow in the lake were consistent over both sampling periods. Furthermore, temporal differentiation existed within each site between the years. Populations of perch appear to cluster in different patches in the lake that harbour genetically differentiated groups of fish. Hence, limited migration and barriers to dispersal can persist over time, even at a very small geographical scale and in an open aquatic environment.

    Place, publisher, year, edition, pages
    Tucson: Evolutionary Ecology Ltd., 2009
    Keywords
    Barriers to gene flow, Microsatellites, Perca fluviatilis L, Small-scale genetic divergence, Spatiotemporal stability
    National Category
    Biological Sciences
    Research subject
    Animal Ecology
    Identifiers
    urn:nbn:se:uu:diva-107228 (URN)000269674500009 ()
    Available from: 2009-07-30 Created: 2009-07-30 Last updated: 2018-05-31Bibliographically approved
    3. Genetic and morphological divergence reveals local subdivision of perch (Perca fluviatilis L.)
    Open this publication in new window or tab >>Genetic and morphological divergence reveals local subdivision of perch (Perca fluviatilis L.)
    2009 (English)In: Biological Journal of the Linnean Society, ISSN 0024-4066, E-ISSN 1095-8312, Vol. 96, no 4, p. 746-758Article in journal (Refereed) Published
    Abstract [en]

    The level of gene flow is an important factor influencing genetic differentiation between populations. Typically, geographic distance is considered to be the major factor limiting dispersal and should thus only influence the degree of genetic divergence at larger spatial scales. However, recent studies have revealed the possibility for small-scale genetic differentiation, suggesting that the spatial scale considered is pivotal for finding patterns of isolation by distance. To address this question, genetic and morphological differentiation were studied at two spatial scales (range 2–13 km and range 300 m to 2 km) in the perch (Perca fluviatilis L.) from the east coast archipelago of Sweden, using seven microsatellite loci and geometric morphometrics. We found highly significant genetic differentiation between sampled locations at both scales. At the larger spatial scale, the distance not affecting the level of divergence. At the small scale, however, we found subtle patterns of isolation by distance. In addition, we also found morphological divergence between locations, congruent with a spatial separation at a microgeographic scale, most likely due to phenotypic plasticity. The present study highlights the importance of geographical scale and indicates that there might be a disparity between the dispersal capacity of a species and the actual movement of genes. Thus, how we view the environment and possible barriers to dispersal might have great implications for our ability to fully understand the evolution of genetic differentiation, local adaptation, and, in the end, speciation.

    Place, publisher, year, edition, pages
    Wiley-Blackwell, 2009
    Keywords
    Differentiation, Dispersal, Gene flow, Isolation by distance, Microsatellites, Morphometrics
    National Category
    Biological Sciences
    Research subject
    Animal Ecology
    Identifiers
    urn:nbn:se:uu:diva-107229 (URN)10.1111/j.1095-8312.2008.01149.x (DOI)000264730400004 ()
    Available from: 2009-07-30 Created: 2009-07-30 Last updated: 2017-12-13Bibliographically approved
    4. Population differentiation in perch Perca fluviatilis: environmental effects on gene flow?
    Open this publication in new window or tab >>Population differentiation in perch Perca fluviatilis: environmental effects on gene flow?
    2010 (English)In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 76, no 5, p. 1159-1172Article in journal (Refereed) Published
    Abstract [en]

    Environmental parameters were used to investigate barriers to gene flow and genetic differentiation in the Eurasian perch (Perca fluviatilis L.) at a small geographical scale in an archipelago system. Significant genetic differentiation was found among locations. Distance per se did not play a major role in the reduction of gene flow. Instead, the largest genetic differences between populations correlated with major changes in environmental conditions, such as temperature at time of spawning. The results show that genetic divergence can arise between populations in habitats thought to be highly connected, and that environmental variables can influence the level of gene flow between populations, including those that are at small spatial scales (tens of kilometres). The importance of a landscape approach when investigating genetic differentiation and defining barriers to gene flow is highlighted.

    Keywords
    barriers to gene flow; landscape genetics; microsatellite DNA; Perca fluviatilis L; population differentiation
    National Category
    Ecology
    Research subject
    Animal Ecology
    Identifiers
    urn:nbn:se:uu:diva-107244 (URN)10.1111/j.1095-8649.2010.02565.x (DOI)000276403000006 ()
    Available from: 2009-07-30 Created: 2009-07-30 Last updated: 2017-12-13Bibliographically approved
    5. The effect of local population dynamics on patterns of isolation by distance
    Open this publication in new window or tab >>The effect of local population dynamics on patterns of isolation by distance
    2010 (English)In: Ecological Informatics, ISSN 1574-9541, Vol. 5, no 3, p. 167-172Article in journal (Refereed) Published
    Abstract [en]

    Isolation-by-distance (IBD) is a widely used model explaining population structure and how gene flow decreases with increasing distances. It is biologically intuitive that populations which rarely exchange individuals should drift apart genetically. However, the model is based on the assumptions that populations are large, equal in size and stable over time - conditions that are unlikely to occur in natural conditions. The model has been challenged in the past, for example, in the light of metapopulations or variance in reproductive success. However, an appraisal of the assumption of a large and stable population size per se is lacking. We investigate the robustness of the results concerning IBD patterns when smaller and fluctuating population sizes, or differences in population size are allowed. Through computer simulations we show that allowing for different population sizes and randomly fluctuations leads to unpredictable patterns regarding the results concerning gene flow and IBD. A pattern of IBD could be the result of high gene flow or no gene flow at all, depending on how populations differ in size and how they fluctuate. Adding environmental noise (white, red and blue noise corresponding to random, positive and negative autocorrelation respectively) gives even more unpredictable results concerning patterns of IBD. Our results have important implications for genetic and conservation research. Interpreting an IBD pattern, or lack thereof, is not as easy as earlier thought and needs to be more thoroughly explored.

     

    Keywords
    Isolation-by-distance, Wright’s Island model, effective population size, stepping stone model, FST, computer simulations
    National Category
    Biological Sciences
    Research subject
    Animal Ecology
    Identifiers
    urn:nbn:se:uu:diva-107249 (URN)10.1016/j.ecoinf.2009.12.003 (DOI)000277916000002 ()
    Available from: 2009-07-30 Created: 2009-07-30 Last updated: 2016-04-18Bibliographically approved
  • 32.
    Bergek, Sara
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Björklund, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Cryptic barriers to dispersal within a lake allow genetic differentiation of Eurasian perch2007In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 61, no 8, p. 2035-2041Article in journal (Refereed)
    Abstract [en]

    Gene flow between coexisting or nearby populations normally prevents genetic divergence and local adaptation. Despite this, there are an increasing number of reports of sympatric sister taxa, indicating potential divergence and speciation in the face of gene flow. A large number of such reported cases involve lake-dwelling fish, which are expected to run into few physical barriers to dispersal within their aquatic habitat. However, such cases may not necessarily reflect sympatric speciation if cryptic dispersal barriers are common in lakes and other aquatic systems. In this study, we examined genetic differentiation in perch (Perca fluviatilis L.) from nine locations in a single, small lake (24 km(2)), using microsatellites. We detected significant genetic differentiation in all but two pairwise comparisons. These patterns were not consistent with divergence by distance or the existence of kin groups. Instead, they suggest that cryptic barriers to dispersal exist within the lake, allowing small-scale genetic divergence. Such an observation suggests that allopatric (or parapatric) divergence may be possible, even in small, apparently homogenous environments such as lakes. This has important consequences for how we currently view evidence from nature for sympatric speciation.

  • 33.
    Bergek, Sara
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Björklund, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Genetic and morphological divergence reveals local subdivision of perch (Perca fluviatilis L.)2009In: Biological Journal of the Linnean Society, ISSN 0024-4066, E-ISSN 1095-8312, Vol. 96, no 4, p. 746-758Article in journal (Refereed)
    Abstract [en]

    The level of gene flow is an important factor influencing genetic differentiation between populations. Typically, geographic distance is considered to be the major factor limiting dispersal and should thus only influence the degree of genetic divergence at larger spatial scales. However, recent studies have revealed the possibility for small-scale genetic differentiation, suggesting that the spatial scale considered is pivotal for finding patterns of isolation by distance. To address this question, genetic and morphological differentiation were studied at two spatial scales (range 2–13 km and range 300 m to 2 km) in the perch (Perca fluviatilis L.) from the east coast archipelago of Sweden, using seven microsatellite loci and geometric morphometrics. We found highly significant genetic differentiation between sampled locations at both scales. At the larger spatial scale, the distance not affecting the level of divergence. At the small scale, however, we found subtle patterns of isolation by distance. In addition, we also found morphological divergence between locations, congruent with a spatial separation at a microgeographic scale, most likely due to phenotypic plasticity. The present study highlights the importance of geographical scale and indicates that there might be a disparity between the dispersal capacity of a species and the actual movement of genes. Thus, how we view the environment and possible barriers to dispersal might have great implications for our ability to fully understand the evolution of genetic differentiation, local adaptation, and, in the end, speciation.

  • 34.
    Bergek, Sara
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Olsson, Jens
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    Spatiotemporal analysis shows stable genetic differentiation and barriers to dispersal in the Eurasian perch (Perca fluviatilis L.)2009In: Evolutionary Ecology Research, ISSN 1522-0613, E-ISSN 1937-3791, Vol. 11, no 5, p. 827-840Article in journal (Refereed)
    Abstract [en]

    Background: Recently, unexpected or cryptic barriers to gene flow causing genetic discontinuities have been found in a number of animal taxa, even in apparently highly connected areas such as aquatic environments. 

    Goal: Investigate the temporal stability of previously documented microgeographic genetic structure in a fish.

    Organism: Eurasian perch (Perca fluviatilis L.)

    Method: We sampled four locations over a period of 2 years. We used six microsatellites to investigate population differentiation. We compared within-year to between-year differentiation.

    Results: The significant genetic differentiation found between locations in 2004 was still present in 2006. The strongest barriers to gene flow in the lake were consistent over both sampling periods. Furthermore, temporal differentiation existed within each site between the years. Populations of perch appear to cluster in different patches in the lake that harbour genetically differentiated groups of fish. Hence, limited migration and barriers to dispersal can persist over time, even at a very small geographical scale and in an open aquatic environment.

  • 35.
    Bergek, Sara
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Sundblad, Göran
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    Björklund, Mats
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Population differentiation in perch Perca fluviatilis: environmental effects on gene flow?2010In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 76, no 5, p. 1159-1172Article in journal (Refereed)
    Abstract [en]

    Environmental parameters were used to investigate barriers to gene flow and genetic differentiation in the Eurasian perch (Perca fluviatilis L.) at a small geographical scale in an archipelago system. Significant genetic differentiation was found among locations. Distance per se did not play a major role in the reduction of gene flow. Instead, the largest genetic differences between populations correlated with major changes in environmental conditions, such as temperature at time of spawning. The results show that genetic divergence can arise between populations in habitats thought to be highly connected, and that environmental variables can influence the level of gene flow between populations, including those that are at small spatial scales (tens of kilometres). The importance of a landscape approach when investigating genetic differentiation and defining barriers to gene flow is highlighted.

  • 36.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Are female ornaments different from those of males? The pipefish evidence1999In: Behaviour and Conservation of Littoral Fishes: Based on the symposium "Behaviour and Conservation of littoral fishes" held at ISPA(Lisboa) 0n 15-18 April 1998 / [ed] Almada, V.C., Oliveira, R.F. & Gonçalves, E.J., Lisboa: ISPA , 1999, p. 231-248Chapter in book (Other academic)
  • 37.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Coexistence, size overlap and population regulation in tidal vs non-tidal Palaemon prawns1982In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 54, no 1, p. 1-7Article in journal (Refereed)
    Abstract [en]

    The effect of increased habitat heterogeneity in tidal areas on coexistence between Palaemon prawns was studied at eight sites along the European Atlantic coast. Two species which are sympatric in non-tidal areas, Palaemon adspersus Rathke and P. squilla (L.) are largely allopatric in tidal areas, and the sympatric size difference decreases in allopatry. In tidal areas the smaller species, P. squilla, is restricted to brown algal belts and rockpools. A third species, P. serratus (Pennant), larger than the others, occurs under oceanic salinities in subtidal brown algal belts and there has forced P. squilla to restrict its habitat distribution to adjacent intertidal rockpools. At estuarine salinities, however, P. squilla also inhabits the brown algal belts. A larger diel variation in stomach fullness index in P. squilla than in P. adspersus persists in non-tidal areas. Abiotic factors probably restrict the two largest species, viz. P. adspersus and P. serratus, to subtidal environments; these species are sensitive to the extremes in salinity, temperature or O2 levels characteristic of the intertidal zone. Competition and/or predation probably relegates P. squilla to the intertidal zone. In non-tidal areas, where this zone is reduced, P. squilla increases its niche width and coexists with P. adspersus, and the size differentiation associated with sympatry may reduce interspecific competition.

  • 38.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Different reproductive success at low salinity determines the estuarine distribution of two Palaemon prawn species1985In: Holarctic ecology, ISSN 0105-9327, Vol. 8, no 1, p. 49-52Article in journal (Refereed)
  • 39.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Egg competition in a sex-role reversed pipefish: subdominant females trade reproduction for growth1991In: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 45, no 3, p. 770-774Article in journal (Refereed)
  • 40.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Evolutionary biology: Pregnant fathers in charge2010In: Nature, ISSN 0028-0836, E-ISSN 1476-4687, Vol. 464, no 7287, p. 364-365Article in journal (Refereed)
  • 41.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Many mates make male pipefish choosy1995In: Behaviour, ISSN 0005-7959, E-ISSN 1568-539X, Vol. 132, no 3-4, p. 213-218Article in journal (Refereed)
    Abstract [en]

    In the sex-role reversed pipefish Syngnathus typhle males search for mates, and prefer to mate with large rather than small females. When mate density was experimentally manipulated, males exerted a mate choice only under high mate density, whereas no mate choice could be demonstrated under low mate density. Hence, when males are infrequently encountered, males reduce the costs associated with an extended mate search by accepting females that otherwise would have been rejected.

  • 42.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Mating systems and sex allocation1997In: Behavioural Ecology of Teleost Fishes / [ed] Godin, J.-G. J., Oxford: Oxford Univ. Press , 1997, p. 237-265Chapter in book (Other academic)
  • 43.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Niche differentiation between two littoral prawns in Gullmar Fjord, Sweden: Palaemon adsperus and P. squilla1980In: Holarctic ecology, ISSN 0105-9327, Vol. 3, no 2, p. 111-115Article in journal (Refereed)
  • 44.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Parental care: why, who and how much? Book review of "The evolution of Parental Care" by T. H. Clutton-Brock1992In: Trends in Ecology & Evolution, ISSN 0169-5347, E-ISSN 1872-8383, Vol. 7, no 2, p. 67-68Article, book review (Other academic)
  • 45.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Reproductive adaptations in two Palaemon prawn species with differing habitat requirements1984In: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 17, no 1, p. 77-83Article in journal (Refereed)
  • 46.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Risky sex: male pipefishes mate at random in the presence of a predator1993In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 46, no 1, p. 169-175Article in journal (Refereed)
    Abstract [en]

    Whether the presence of a predator alters courtship behaviour and mating in male pipefish, Syngnathus typhle, was studied experimentally by first allowing a male to choose between a large and a small female in an enclosure. The females were subsequently released to establish with which the male mated. In the presence of an enclosed predator, males were not more active in front of or danced more with larger than smaller females, but in the absence of a predator the larger females received more activity and dancing. Moreover, control males (without a predator) copulated more often with large than with small females, whereas predator-exposed males copulated infrequently and indiscriminately. These differences are most likely to be due to a decrease in male choosiness when a predator is present, as treatment, size and time of the day did not influence the activity of enclosed females. Predator-exposed males courted and copulated less, but each copulation transferred more eggs, compared with the control males. There was no significant difference in total number of eggs transferred to the males' brood pouches between treatments. Thus, the presence of a predator made mating random and minimized conspicuous mating behaviour, thereby decreasing the potential for sexual selection to act under high predation regimes in this pipefish.

  • 47.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Sequential hermaphroditism and the size-advantage hypothesis: an experimental test1990In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 39, no 3, p. 426-433Article in journal (Refereed)
    Abstract [en]

    When members of one sex have a low reproductive success when small and a high reproductive success when large, while members of the opposite sex do relatively better when small and relatively worse when large, sequential hermaphroditism is commonly believed to be favoured by natural selection. This so-called size-advantage hypothesis has not been rigorously tested experimentally. For the hermaphrodite Ophryotrocha puerilis puerilis, a polychaete, in which small individuals are males and large ones females, the hypothesis predicts that reproductive success will increase less with body size for males than for females, eventually promoting sex change in males. Dry body weight of males was not correlated with reproductive rate, whereas there was a positive correlation for females in reproducing pairs. Furthermore, an increment in the size of females affected clutch size and reproductive rate more than did an equal increment in the size of males. Reproductive success of males decreased with size, because females preferred smaller males. At the same time, large males won contests for access to females, although female choice overrode this combat superiority. Therefore, after reaching a certain size a male would not benefit from staying male. Taking into account the relatively low cost of sex change in this species (about 5 days being lost, equivalent to one interbrood interval) sex reversal occurred as predicted by the size-advantage hypothesis.

  • 48.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Sex dimorphism and skewed sex-ratios in the prawn species Palaemon adspersus and P. squilla1981In: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 36, no 2, p. 158-162Article in journal (Refereed)
  • 49.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Evolutionary Biology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Sex role reversal in a pipefish: female ornaments as amplifying handicaps2000In: Annales Zoologici Fennici, ISSN 0003-455X, E-ISSN 1797-2450, Vol. 37, no 1, p. 1-13Article in journal (Refereed)
    Abstract [en]

    The reasons for sex role reversal in the pipefish Syngnathus typhle are reviewed. In this species, females compete for males, which are choosier than females. Before mating, females display a sexual ornament, a cross-wise striped pattern along their body sides. This ornament is here shown to be an amplifier that facilitates for males to tell females of different sizes apart (males prefer larger females). When students were asked to compare bar sizes, where bars differed in "ornamentation", accuracy in estimating size was highest with "heavy ornamented" as compared with "intermediate" or "not ornamented" bars. Moreover, bar size was more accurately judged with crosswise than with lengthwise striped bars, explaining why stripes run cross- rather than lengthwise in females. The ornament is probably costly (it reduces crypsis and may be socially provocative), and it is also attractive to males. Thus, the ornament is best described as an amplifying handicap.

  • 50.
    Berglund, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution, Animal Ecology.
    Sex-change by a polychaete: effects of social and reproductive costs1986In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 67, no 4, p. 837-845Article in journal (Refereed)
1234567 1 - 50 of 372
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