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  • 51.
    Rogell, Björn
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Thörngren, Hanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Zooekologi.
    Laurila, Anssi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Fitness costs associated with low genetic variation are reduced in a harsher environment in amphibian island populations2010Ingår i: Conservation Genetics, ISSN 1566-0621, E-ISSN 1572-9737, Vol. 11, nr 2, s. 489-496Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    A basic premise of conservation geneticists is that low levels of genetic variation are associated with fitness costs in terms of reduced survival and fecundity. These fitness costs may frequently vary with environmental factors and should increase under more stressful conditions. However, there is no consensus on how fitness costs associated with low genetic variation change under natural conditions in relation to the stressfulness of the environment. On the Swedish west coast, natterjack toad Bufo calamita populations show a strong population genetic structure and large variation in the amount of within-population genetic variation. We experimentally examined the survival of natterjack larvae from six populations with different genetic variation in three thermal environments corresponding to (a) the mean temperature of natural ponds (stable, laboratory), (b) a high temperature environment occurring in desiccating ponds (stable, laboratory) and (c) an outdoor treatment mimicking the natural, variable thermal conditions (fluctuating, semi-natural). We found that larvae in the outdoor treatment had poorer survival than larvae in the stable environments suggesting that the outdoor treatment was more stressful. Overall, populations with higher genetic variation had higher larval survival. However, a significant interaction between treatments and genetic variation indicated that fitness costs associated with low genetic variation were less severe in the outdoor treatment. Thus, we found no support for the hypothesis that fitness costs associated with low genetic variation increase under more stressful conditions. Our results suggest that natural thermal stress may mask fitness losses associated with low genetic variation in these populations.

  • 52.
    Rogell, Björn
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Thörngren, Hanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Zooekologi.
    Palm, Stefan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Laurila, Anssi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Genetic structure in peripheral populations of the natterjack toad, Bufo calamita, as revealed by AFLP2010Ingår i: Conservation Genetics, ISSN 1566-0621, E-ISSN 1572-9737, Vol. 11, nr 1, s. 173-181Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Decreased fitness due to loss of genetic variation is a well recognised issue in conservation biology. Along the Swedish west coast, the endangered natterjack toad (Bufo calamita) occurs on, for the species, highly unusual habitat of rocky islands. Although the toads inhabit a restricted geographical area (maximum distance between the populations is 71 km), the fragmented nature of the landscape makes the genetic properties of the populations of conservation interest. However, lack of genetic variation found using conventional methods (microsatellites) has impeded genetic studies within these peripheral populations so far. In this study we assess population structure and genetic variation among seven of these fringe populations using 105 polymorphic Amplified Fragment Length Polymorphism (AFLP) loci. We found a well-defined population structure without evidence for isolation by distance, implying restricted gene flow between populations. Additionally, the populations differed in their amount of genetic variation, emphasizing the need to monitor genetically impoverished populations for possible declines mediated by inbreeding depression and reduced adaptive potential. Conservation implications for these unique populations are discussed in the light of our results.

  • 53.
    Rudh, Andreas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Zooekologi.
    Rogell, Björn
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Non-gradual variation in colour morphs of the strawberry poison frog Dendrobates pumilio: genetic and geographical isolation suggest a role for selection in maintaining polymorphism2007Ingår i: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 16, nr 20, s. 4284-4294Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The relative roles that geographical isolation and selection play in driving population divergence remain one of the central questions in evolutionary biology. We approached this question by investigating genetic and morphological variation among populations of the strawberry poison frog, Dendrobates pumilio, in the Bocas del Toro archipelago, Panama. We found significant population genetic structure and isolation by distance based on amplified fragment length polymorphism markers. Snout vent length (SVL), coloration and the extent and size of dorsal black spots showed large variation among the studied populations. Differences in SVL correlated with genetic distance, whereas black spot patterns and other coloration parameters did not. Indeed, the latter characters were observed to be dramatically different between contiguous populations located on the same island. These results imply that neutral divergence among populations may account for the genetic patterns based on amplified fragment length polymorphism markers and SVL. However, selective pressures need to be invoked in order to explain the extraordinary variation in spot size and coverage, and coloration. We discuss the possibility that the observed variation in colour morphs is a consequence of a combination of local variation in both natural selection on an aposematic signal towards visual predators and sexual selection generated by colour morph-specific mate preferences.

  • 54. Ruokonen, Minna
    et al.
    Andersson, Anna-Carin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för evolution, genomik och systematik, Evolutionär funktionsgenomik.
    Tegelström, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Using historical captive stocks in conservation. The case of the lesser white-fronted goose2007Ingår i: Conservation Genetics, ISSN 1566-0621, E-ISSN 1572-9737, Vol. 8, nr 1, s. 197-207Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Many captive stocks of economically or otherwise valuable species were established before the decline of the wild population. These stocks are potentially valuable sources of genetic variability, but their taxonomic identity and actual value is often uncertain. We studied the genetics of captive stocks of the threatened lesser white-fronted goose Anser erythropus maintained in Sweden and elsewhere in Europe. Analyses of mtDNA and nuclear microsatellite markers revealed that 36% of the individuals had a hybrid ancestry. Because the parental species are closely related it is unlikely that our analyses detected all hybrid individuals in the material. Because no ancestral polymorphism or introgression was observed in samples of wild populations, it is likely that the observed hybridisation has occurred in captivity. As a consequence of founder effect, drift and hybridisation, captive stocks were genetically differentiated from the wild populations of the lesser white-fronted goose. The high level of genetic diversity in the captive stocks is explained at least partially by hybridisation. The present captive stocks of the lesser white-fronted goose are considered unsuitable for further reintroduction, or supplementation: hybridisation has involved three species, the number of hybrids is high, and all the investigated captive stocks are similarly affected. The results highlight the potential shortcomings of using captive-bred individuals in supplementation and reintroduction projects, when the captive stocks have not been pedigreed and bred according to conservation principles.

  • 55.
    Räsänen, Katja
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Söderman, Fredrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Laurila, Anssi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Merila, Juha
    Geographic variation in maternal investment: Acidity affects egg size and fecundity in Rana arvalis2008Ingår i: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 89, nr 9, s. 2553-2562Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Environmental-stress-mediated geographic variation in reproductive parameters has been little studied in natural vertebrate populations outside the context of climatic variation. Based on life-history theory, an increase in the degree of environmental stress experienced by a population should lead to (1) a shift in reproductive allocation from fecundity to offspring quality, (2) stronger trade-offs between reproductive parameters, and (3) changes in the relationship between female phenotype and maternal investment. To test these predictions, we investigated geographic variation in maternal investment of moor frogs (Rana arvalis) in relation to breeding site acidity (pH 4-8). We found that mean egg size increased and clutch size and total reproductive output (TRO) decreased with increasing acidity among 19 Swedish moor frog populations. Tests for variation and co-variation in maternal investment and female size and age in 233 females from a subset of four acid origin (AO) and four neutral origin (NO) populations revealed that clutch size and TRO increased with female size in both acid and neutral environments. However, in AO populations, egg size also increased with female size, and clutch size and TRO with female age, whereas in NO populations, egg size increased with female age. The strength of the egg-size-clutch-size trade-off tended to be stronger in AO than in NO females as expected if the former experience stronger environmental constraints. All in all, these results suggest that environmental acidfication selects for investment in larger eggs at a cost to fecundity, imposes negative effects on reproductive output, and alters the relationship between female phenotype and maternal investment.

  • 56.
    Saether, Stein Are
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Fiske, P.
    Kålås, J.A.
    Kuresoo, A.
    Luigujoe, L.
    Piertney, S.B.
    Sahlman, Tobias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Inferring local adaptation from QST-FST comparisons: neutral genetic and quantitative trait variation in European populations of great snipe2007Ingår i: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 20, nr 4, s. 1563-1576Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We applied a phenotypic QST (PST) vs. FST approach to study spatial variation in selection among great snipe (Gallinago media) populations in two regions of northern Europe. Morphological divergence between regions was high despite low differentiation in selectively neutral genetic markers, whereas populations within regions showed very little neutral divergence and trait differentiation. QST > FST was robust against altering assumptions about the additive genetic proportions of variance components. The homogenizing effect of gene flow (or a short time available for neutral divergence) has apparently been effectively counterbalanced by differential natural selection, although one trait showed some evidence of being under uniform stabilizing selection. Neutral markers can hence be misleading for identifying evolutionary significant units, and adopting the PST–FST approach might therefore be valuable when common garden experiments is not an option. We discuss the statistical difficulties of documenting uniform selection as opposed to divergent selection, and the need for estimating measurement error. Instead of only comparing overall QST and FST values, we advocate the use of partial matrix permutation tests to analyse pairwise QST differences among populations, while statistically controlling for neutral differentiation.

  • 57.
    Sahlsten, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Thörngren, Hanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Zooekologi.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Inference of hazel grouse population structure using multilocus data: a landscape genetic approach2008Ingår i: Heredity, ISSN 0018-067X, E-ISSN 1365-2540, Vol. 101, nr 6, s. 475-482Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
    Abstract [en]

    In conservation and management of species it is important to make inferences about gene flow, dispersal and population structure. In this study, we used 613 georeferenced tissue samples from hazel grouse (Bonasa bonasia) where each individual was genotyped at 12 microsatellite loci to make inference on population genetic structure, gene flow and dispersal in northern Sweden. Observed levels of genetic diversity suggest that Swedish hazel grouse do not suffer loss of genetic diversity compared with other grouse species. We found significant F-IS (deviation from Hardy-Weinberg expectations) over the entire sample using jack-knifed estimators over loci, which is most likely explained by a Wahlund effect. With the use of spatial autocorrelation methods, we detected significant isolation by distance among individuals. Neighbourhood size was estimated in the order of 62-158 individuals corresponding to a dispersal distance of 950-1500 m. Using a spatial statistical model for landscape genetics to infer the number of populations and the spatial location of genetic discontinuities between these populations we found indications that Swedish hazel grouse are divided into a northern and a southern population. We could not find a sharp border between these two populations and none of the observed borders appeared to coincide with any potential geographical barriers. These results imply that gene flow appears somewhat unrestricted in the boreal taiga forests of northern Sweden and that the two populations of hazel grouse in Sweden may be explained by the post-glacial reinvasion history of the Scandinavian Peninsula. Heredity (2008) 101, 475-482; doi: 10.1038/hdy.2008.94; published online 1 October 2008

  • 58.
    Sahlsten, Jonas
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Wickström, Fredrik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Hazel grouse Bonasa bonasia population dynamics in a fragmented landscape: a metapopulation approach2010Ingår i: Wildlife Biology, ISSN 0909-6396, E-ISSN 1903-220X, Vol. 16, nr 1, s. 35-46Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    If the deterministic threats of fragmentation can be stopped or reversed, species may find opportunities to disperse between patches and reduce the risk of extinction. In order to realise these opportunities and apply them to conservation programmes, it is necessary to understand the dynamics involved and to estimate which capacity is high enough to sustain a population at the landscape level. In a regional population consisting of several subpopulations, the incidence function model (IFM) is a stochastic, spatially-realistic patch occupancy model which can be applied using few parameters. With this model one can simulate and manipulate a patch network for a species. In IFM, the extinction probability is assumed to be proportional to local population size which in turn is assumed to be proportional to the local patch area. Although, the basic area of patches is of importance, influence from the geometric shape of patches may be equally or more important to determine potential incidence of a species in a particular patch. Basic area measurements might overestimate the probability of occupancy and/or capacity of a certain patch network to sustain a metapopulation. One applicable method to use in dealing with regional dynamics in fragmented landscapes is metapopulation capacity; derived from metapopulation theory, this method can be used to rank different patch networks. In our study, we examine if there is any difference in occupancy level and capacity between four different area scenarios. This allows us to determine if the basic area measurement of patches can result in a biased estimation of population viability in a specific landscape. It is concluded that perimeter-area related measures of patch size combined with capacity could be a more important measure for estimation of population dynamics and impact of landscape changes compared to basic area measurement and occupancy levels.

  • 59.
    Sandvik Widemo, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Male but not female pipefish copy mate choice.2006Ingår i: Behavioral Ecology, Vol. 17, s. 255-259Artikel i tidskrift (Refereegranskat)
  • 60.
    Schäfer, M. L.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Lundström, J. O.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Petersson, E.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Zooekologi.
    Comparison of mosquito (Diptera : Culicidae) populations by wetland type and year in the lower River Dalalven region, Central Sweden2008Ingår i: Journal of Vector Ecology, ISSN 1081-1710, E-ISSN 1948-7134, Vol. 33, nr 1, s. 150-157Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We studied adult mosquito assemblages in six wetlands, representing three types (wet meadow, alder swamp, and bog), in the lower part of the River Dalalven in Central Sweden during three consecutive years (2000-2002) and evaluated the influence of wetland type and year. Mosquito abundance differed significantly between years but not between wetland types. Mosquito species richness showed no significant variation between years or wetland types. Cluster analysis based on percentage of similarity resulted in three clusters, with high similarity between all wetlands in 2000. Ordination analysis showed that mosquito assemblages were mainly correlated with wetland type and water level increase in the previous month. Hydrological conditions varied between the years and between the wetland types, and our collections also included a year (2000) with extreme flood situations. The floodwater mosquito species Ochlerotatus sticticus was the predominant species with a strong influence on the whole study due to its long-range dispersal ability. The entire region suffered from enormous numbers of Oc. sticticus in 2000. The data from this study provided the basis for the initiation of a mosquito control project in the region.

  • 61.
    Segelbacher, Gernot
    et al.
    Dept Wildlife Ecology and Management, University Freiburg.
    Strand, Tanja
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Populationsbiologi och naturvårdsbiologi.
    Quintela, Maria
    Dept of Animal Biology, Plant Biology and Ecology, Faculty of Science, University of A Coruña.
    Axelsson, Tomas
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten.
    Jansman, Hugh
    Alterra Wageningen UR.
    Koelewijn, Peter
    Nunhems BV.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Historic and current populations of black grouse in central Europe – evidence for rapid loss of genetic diversity2011Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Black grouse (Tetrao tetrix) in central Europe have undergone a severe contraction of their range with only a few small isolated remaining populations. We here compare genetic diversity of two contemporary populations (Sallandse Heuvelrug, Netherlands and Lüneburger Heide, Germany) with historic samples from the same range collected decades ago. We use both neutral and MHC markers to test whether present small and highly fragmented populations hold lower genetic diversity compared to the former larger population. For this we applied three different types of genetic markers: nine microsatellites and 21 SNPs (Single Nucleotide Polymorphisms) which both have been found to be neutral, and two functional MHC (Major Histocompatibility Complex) genes that are presumably under selection. The contemporary small isolated populations displayed lower neutral genetic diversity compared to the historic samples. A similar trend was found for genotypes at MHC class II loci. Furthermore, population structure was more pronounced among contemporary populations compared to historic populations for microsatellites and SNPs. This effect was not as distinct for MHC which suggests that MHC has been subjected to balancing selection in the past, a process upholding genetic variation and minimizing population structure for such markers. As predicted from theory, drift is the most potent evolutionary processes affecting genetic variation at small population sizes. Genetic differentiation among present populations highlights the strong affects of population decline and habitat loss due to anthropogenic land use changes on genetic structure of natural populations. 

  • 62. Segelbacher, Gernot
    et al.
    Wegge, P.
    Sivkov, A.V.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Kin groups in closely spaced capercaillie leks2007Ingår i: Journal of Ornithology = Journal fur Ornithologie, ISSN 0021-8375, E-ISSN 1439-0361, Vol. 148, nr 1, s. 79-84Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We quantified the genetic structure among 58 capercaillie (Tetrao urogallus) from three closely spaced leks in boreal Russia using ten microsatellite loci. We did not find significant structuring with respect to lek membership in an overall analysis. However, all but one individual could be strongly assigned to one of two genetic clusters, which we interpret as reflecting different local lineages or extended family groups. There was evidence for structuring among some clusters within leks, and one smaller lek consisted of nine out of ten males from one cluster, which could reflect kin biasing of lek membership. One cluster was apparently outperforming the other, since nine out of ten juveniles sampled belonged to it.

  • 63.
    Skoglund, Pontus
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för evolution, genomik och systematik, Evolutionsbiologi.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Sequence Polymorphism in Candidate Genes for Differences in Winter Plumage between Scottish and Scandinavian Willow Grouse (Lagopus lagopus)2010Ingår i: PLoS one, ISSN 1932-6203, Vol. 5, nr 4, s. e10334-Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Background: Population variation in the degree of seasonal polymorphism is rare in birds, and the genetic basis of this phenomenon remains largely undescribed. Both sexes of Scandinavian and Scottish Willow grouse (Lagopus lagopus) display marked differences in their winter phenotypes, with Scottish grouse retaining a pigmented plumage year-round and Scandinavian Willow grouse molting to a white morph during winter. A widely studied pathway implicated in vertebrate pigmentation is the melanin system, for which functional variation has been characterised in many taxa. Methodology/Principal Findings: We sequenced coding regions from four genes involved in melanin pigmentation (DCT, MC1R, TYR and TYRP1), and an additional control involved in the melanocortin pathway (AGRP), to investigate the genetic basis of winter plumage in Lagopus. Despite the well documented role of the melanin system in animal coloration, we found no plumage-associated polymorphism or evidence for selection in a total of similar to 2.6 kb analysed sequence. Conclusions/Significance: Our results indicate that the genetic basis of alternating between pigmented and unpigmented seasonal phenotypes is more likely explained by regulatory changes controlling the expression of these or other loci in the physiological pathway leading to pigmentation.

  • 64. Sloboda, Michal
    et al.
    Mihalca, Andrei Daniel
    Falka, Istvan
    Petrzelkova, Klara J.
    Carlsson, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Ghira, Ioan
    Modry, David
    Are gobiid fish more susceptible to predation if parasitized by Eustrongylides excisus?: An answer from robbed snakes2010Ingår i: Ecological research, ISSN 0912-3814, E-ISSN 1440-1703, Vol. 25, nr 2, s. 469-473Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aspects of the predator-prey relationship between dice snake, Natrix tessellata and gobiid fish infected with Eustrongylides excisus were studied in Lake Sinoe, Romania. A population of snakes residing here shows a high prevalence of subcutaneous larvae of this nematode. The hypothesis of the altered motility in infected fish leading to increased depredation by snakes was tested by comparing gobiids collected from dice snakes with gobiids caught via electrofishing. Out of a total of seven identified gobiid species, three were used for analysis: syrman goby Neogobius syrman, mushroom goby Neogobius eurycephalus, and round goby Neogobius melanostomus. No significant differences in prevalence and intensity of E. excisus infection were found between fish caught by snakes and those obtained by electrofishing. However, significantly higher abundance of E. excisus larvae in fish caught by snakes was reported. These findings suggest limited influence of the presence of E. excisus larvae in studied gobiids regarding their susceptibility to predation by dice snakes.

  • 65. Sorensen, Jesper Givskov
    et al.
    Pekkonell, Minna
    Lindgren, Beatrice
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Loeschcke, Volker
    Laurila, Anssi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Merila, Juha
    Complex patterns of geographic variation in heat tolerance and Hsp70 expression levels in the common frog Rana temporaria2009Ingår i: Journal of Thermal Biology, ISSN 0306-4565, E-ISSN 1879-0992, Vol. 34, nr 1, s. 49-54Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    1. We tested for geographical variation in heat tolerance and Hsp70 expression levels of Rana temporaria tadpoles along a 1500 km long latitudinal gradient in Sweden. 2. Temperature tolerance of the hatchling tadpoles did not differ among populations, but they tolerated stressful hot temperatures better than 2 weeks older tadpoles. 3. Among 2-week old tadpoles, the southern population tolerated 32 C better than tadpoles from other populations. A parallel difference was found in Hsp70 expression, with the southern population showing the highest expression level. Nevertheless, at a highly stressful temperature (36 C) the northern population showed highest tolerance. 4. The heat shock pre-treatment increased heat tolerance of the tadpoles. The possible adaptive role of Hsp70 for thermal tolerance and climatic adaptation in R. temporaria tadpoles is discussed.

  • 66.
    Strand, Tanja
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Populationsbiologi och naturvårdsbiologi.
    Segelbacher, Gernot
    Dept Wildlife Ecology and Management, University Freiburg.
    Quintela, Maria
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi. Dept of Animal Biology, Plant Biology and Ecology, Faculty of Science, University of A Coruña.
    Xiao, Lyngyun
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Axelsson, Tomas
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Can balancing selection on MHC loci counteract genetic drift in small fragmented populations of black grouse?2012Ingår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 2, nr 2, s. 341-353Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The ability of natural populations to adapt to new environmental conditions is crucial for their survival and partly determined by the standing genetic variation in each population. Populations with higher genetic diversity are more likely to contain individuals that are better adapted to new circumstances than populations with lower genetic diversity. Here we use both neutral and MHC markers to test whether small and highly fragmented populations hold lower genetic diversity than large ones. We use black grouse as it is distributed across Europe and found in populations with varying degrees of isolation and size. We sampled eleven different populations; five continuous, three isolated and three small and isolated. We tested patterns of genetic variation in these populations using three different types of genetic markers: nine microsatellites and 21 SNPs (Single Nucleotide Polymorphisms) which both were found to be neutral, and two functional MHC (Major Histocompatibility Complex) genes that are presumably under selection. The small isolated populations displayed significantly lower neutral genetic diversity compared to continuous populations. A similar trend, but not as pronounced, was found for genotypes at MHC class II loci. Populations were less divergent at MHC genes compared to neutral markers. Measures of genetic diversity and population genetic structure were positively correlated among microsatellites and SNPs, but none of them were correlated to MHC when comparing all populations. Our results suggest that balancing selection at MHC loci does not counteract the power of genetic drift when populations get small and fragmented. 

  • 67.
    Strand, Tanja
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Populationsbiologi och naturvårdsbiologi.
    Wang, Biao
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Populationsbiologi och naturvårdsbiologi.
    Meyer-Lucht, Yvonne
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Populationsbiologi och naturvårdsbiologi.
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Evolutionary history of black grouse BLB1 and BLB2 revealed through single locus sequence-based typingManuskript (preprint) (Övrigt vetenskapligt)
  • 68.
    Strand, Tanja
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Westerdahl, Helena
    Höglund, Jacob
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Alatalo, Rauno V.
    Siitari, Heli
    The MHC class II of the Black grouse (Tetrao tetrix) consists of low numbers of B and Y genes with variable diversity and expression2007Ingår i: Immunogenetics, ISSN 0093-7711, E-ISSN 1432-1211, Vol. 59, nr 9, s. 725-734Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We found that the Black grouse (Tetrao tetrix) possess low numbers of Mhc class II B (BLB) and Y (YLB) genes with variable diversity and expression. We have therefore shown, for the first time, that another bird species (in this case, a wild lek-breeding galliform) shares several features of the simple Mhc of the domestic chicken (Gallus gallus). The Black grouse BLB genes showed the same level of polymorphism that has been reported in chicken, and we also found indications of balancing selection in the peptide-binding regions. The YLB genes were less variable than the BLB genes, also in accordance with earlier studies in chicken, although their functional significance still remains obscure. We hypothesize that the YLB genes could have been under purifying selection, just as the mammal Mhc-E gene cluster.

  • 69.
    Svensson, Magnus
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Rintamäki, Pekka T.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Birkhead, Tim R.
    Griffith, Simon C.
    Lundberg, Arne
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Impaired hatching success and male-biased embryo mortality in Tree Sparrows2007Ingår i: Journal of Ornithology = Journal fur Ornithologie, ISSN 0021-8375, E-ISSN 1439-0361, Vol. 148, nr 1, s. 117-122Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During the past 30 years, many species of farmland birds have declined dramatically in numbers in Northern Europe, a trend coinciding with a tremendous intensification of agriculture, although the exact causes of these declines remain unclear. One of the worst affected species is the Tree Sparrow (Passer montanus). We studied two Swedish Tree Sparrow populations during the years 1996–2004 and found that in both populations, almost half of all laid eggs remained unhatched. This led us to investigate whether the eggs failed to hatch because of: (1) eggs not being fertilised or (2) embryo mortality. Our analyses showed that all of the eggs investigated contained sufficient number of sperm for fertilisation and that they also had other visible signs indicating that fertilisation had occurred. Hatching failure was instead shown to result from embryo mortality. Using molecular techniques, we were able to determine that embryo mortality is more likely to affect male embryos than females and that the fledgling sex ratio was consequently highly female biased. The cause of this sex-biased embryo mortality remains unknown, but various potential explanations are discussed.

  • 70.
    Söderman, Fredrik
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    van Dongen, Stefan
    Pakkasmaa, Susanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Merilä, Juha
    Environmental stress increases skeletal fluctuating asymmetry in the moor frog Rana arvalis2007Ingår i: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 151, nr 4, s. 593-604Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Whether fluctuating asymmetry (FA) provides a useful metric indicator of the degree of environmental stress experienced by populations is still a contentious issue. We investigated whether the degree of FA in skeletal elements is useful in elucidating the degree of environmental stress experienced by frog populations, and further, tested the proposition that a trait’s sensitivity to stress—as reflected in the degree of FA—is related to the degree of directional selection experienced by the given trait. We compared the degree of FA in four bilateral skeletal elements of male and female moor frogs (Rana arvalis) originating from low (acidified) and neutral pH populations. While the degree of uncorrected FA was unrelated to the degree of acidity, the growth rate and age of the individuals, the size-corrected FA was significantly higher in low than in neutral pH populations and decreased with individual ages and growth rates. In addition, both measures of FA were significantly higher in males and in particular in traits presumably under high sexual selection as indicated by the degree of sexual size dimorphism. All in all, the results indicate that individuals from acidified localities are smaller, younger and exhibit a significantly higher degree of FA than individuals from neutral pH populations. These results constitute the first assessment of FA in amphibians and suggest that the degree of FA in skeletal traits can be a useful indicator of the degree of environmental stress experienced by amphibian populations.

  • 71. Tejedo, Miguel
    et al.
    Marangoni, Federico
    Pertoldi, Cino
    Richter-Boix, Alex
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Laurila, Anssi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Orizaola, German
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Nicieza, Alfredo G.
    Alvarez, David
    Gomez-Mestre, Ivan
    Contrasting effects of environmental factors during larval stage on morphological plasticity in post-metamorphic frogs2010Ingår i: Climate Research (CR), ISSN 0936-577X, E-ISSN 1616-1572, Vol. 43, nr 1-2, s. 31-39Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In organisms with complex life cycles, environmentally induced plasticity across sequential stages can have important consequences on morphology and life history traits such as developmental and growth rates. However, previous research in amphibians and other ectothermic vertebrates suggests that some morphological traits are generally insensitive to environmental inductions. We conducted a literature survey to examine the allometric responses in relative hind leg length and head shape of post-metamorphic anuran amphibians to induced environmental (temperature, resource level, predation and desiccation risk) variation operating during the larval phase in 44 studies using 19 species. To estimate and compare plastic responses across studies, we employed both an index of plasticity and effect sizes from a meta-analysis. We found contrasting trait responses to different environmental cues. Higher temperatures increased development more than growth rate and induced smaller heads but not overall shifts in hind leg length. In contrast, an increment in resource availability increased growth more than development, with a parallel increase in hind leg length but no change in head shape. Increases in predation risk decreased both development and growth rates and slightly reduced relative hind leg length, but there was no change in head shape. Pond desiccation induced quick development and low growth rates, with no changes in morphology. Across environments, both hind leg and head shape plasticity were positively correlated with growth rate plasticity. However, plasticity of developmental rate was only correlated with head shape plasticity. Overall, these results suggest that environmental trends predicted by global warming projections, such as increasing pond temperature and accelerating pond desiccation, will significantly influence hind leg and head morphology in metamorphic frogs, which may affect performance and, ultimately, fitness.

  • 72.
    Teplitsky, Celine
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution.
    Räsänen, Katja
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution.
    Laurila, Anssi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Adaptive plasticity in stressful environments: Acidity constrains inducible defences in Rana arvalis2007Ingår i: Evolutionary Ecology Research, ISSN 1522-0613, E-ISSN 1937-3791, Vol. 9, nr 3, s. 447-458Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Questions: How do environmental stressors affect the expression of adaptive phenotypicplasticity? Is there inter-population variation in these effects?   Hypothesis: Acid stress constrains the expression of inducible defences by decreasinginvestment in defences or by increasing the costs of investment. Organisms originating fromneutral environments suffer more from acid stress than organisms originating from acidenvironments.   Organism: Tadpoles of Rana arvalis, originating from two different populations (acid andneutral). This species displays inducible defences in response to insect predators (here dragonflylarvae).   Methods: A laboratory experiment with a factorial design crossing two factors: predatorpresence (present vs. absent) and acidity (neutral vs. acid). We tested the effects of experimentaltreatment on tadpole morphology as well as age and size at metamorphosis.   Results: Tadpoles from the neutral origin population invested less in inducible defences (tailfin depth) in the acid than in the neutral treatment. In contrast, tadpoles from the acid originpopulation were able to respond equally well to predators in both pH treatments. pH-relatedcosts differed between populations: while tadpoles from the neutral origin population sufferedfrom acid stress in terms of reduced developmental rate, those from the acid origin populationseemed to suffer from neutral stress in terms of reduced size at metamorphosis.

  • 73.
    Teplitsky, Céline
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Laurila, Anssi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Flexible defense strategies: competition modifies investment in behavioral vs. morphological defenses2007Ingår i: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 88, nr 7, s. 1641-1646Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Competition is predicted to affect the expression of inducible defenses, but because costs of behavioral and morphological antipredator defenses differ along resource gradients, its effects on defenses may depend on the traits considered. We tested the predictions from different defense models in tadpoles of the common frog Rana temporaria, which exhibit both types of defenses. In an outdoor experiment, we exposed the tadpoles to nonlethal predators (Aeshna dragonfly larvae) and to a gradient of intraspecific competition. Morphological responses did not follow any of the expected patterns, since investment in defense was not affected by resource level. Instead, tail depth decreased in the absence of predators. Behavioral defenses followed a state-dependent model. Overall, the defense strategy of the tadpoles revealed a shift from morphological and behavioral defenses at low tadpole density to morphological defense only at high density. This difference probably reflects the different efficiency of the defenses. Hiding is an effective means of defense, but it is unsustainable when resources are scarce. Morphological responses become more important with increasing density to compensate for the increase in behavioral risk-taking. Our results indicate that competition can strongly affect reaction norms of inducible defenses and highlight the importance of integrating ecological parameters that affect the cost–benefit balance of phenotypic plasticity.

  • 74.
    Thulin, Carl Gustaf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Hur gör harar i andra länder?2006Ingår i: Svensk Jakt, Vol. 10, s. 80-81Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 75.
    Thulin, Carl Gustaf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Microsatellite investigation of roe deer (Capreolus capreolus) in Scandinavia reveals genetic differentiation of a Baltic Sea Island population.2006Ingår i: European Journal of Wildlife Research, Vol. 52, s. 228-235Artikel i tidskrift (Refereegranskat)
  • 76.
    Thulin, Carl Gustaf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Släktskap mellan rådjur2006Ingår i: Svensk Jakt, Vol. 9, s. 98-100Artikel i tidskrift (Övrig (populärvetenskap, debatt, mm))
  • 77.
    Thulin, Carl Gustaf
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Stone, J
    Tegelström, Håkan
    Institutionen för evolution, genomik och systematik. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Walker, CW
    Species assignment and hybrid identification among Scandinavian hares Lepus europaeus and L. timidus.2006Ingår i: Wildlife Biology, Vol. 12, s. 29-38Artikel i tidskrift (Refereegranskat)
  • 78.
    Thulin, Carl-Gustaf
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Simberloff, D.
    Barun, A.
    McCracken, G.
    Pascal, M.
    Islam, M.A.
    Genetic divergence in the small Indian mongoose (Herpestes auropunctatus), a widely distributed invasive species2006Ingår i: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 15, nr 13, s. 3947-3956Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The combination of founder events, random drift and new selective forces experienced by introduced species typically lowers genetic variation and induces differentiation from the ancestral population. Here, we investigate microsatellite differentiation between introduced and native populations of the small Indian mongoose (Herpestes auropunctatus). Many expectations based on introduction history, such as loss of alleles and relationships among populations, are confirmed. Nevertheless, when applying population assignment methods to our data, we observe a few specimens that are incorrectly assigned and/or appear to have a mixed ancestry, despite estimates of substantial population differentiation. Thus, we suggest that population assignments of individuals should be viewed as tentative and that there should be agreement among different algorithms before assignments are applied in conservation or management. Further, we find no congruence between previously reported morphological differentiation and the sorting of microsatellite variation. Some introduced populations have retained much genetic variation while others have not, irrespective of morphology. Finally, we find alleles from the sympatric grey mongoose (Herpestes edwardsii) in one small Indian mongoose within the native range, suggesting an alternative explanation for morphological differentiation involving a shift in female preferences in allopatry.

  • 79. Tiira, K
    et al.
    Laurila, Anssi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Enberg, K
    Piironen, J
    Aikio, S
    Ranta, E
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Primmer, CR
    Do dominants have higher heterozygosity? Social status and genetic variation in brown trout, Salmo trutta2006Ingår i: Behavioral Ecology and Sociobiology, Vol. 59, s. 657-665Artikel i tidskrift (Refereegranskat)
  • 80. Ursenbacher, Sylvain
    et al.
    Carlsson, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Helfer, Veronique
    Tegelström, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution.
    Fumagalli, Luca
    Phylogeography and Pleistocene refugia of the Adder (Vipera berus) as inferred from mitochondrial DNA sequence data2006Ingår i: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 15, nr 11, s. 3425-3437Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In order to contribute to the debate about southern glacial refugia used by temperate species and more northern refugia used by boreal or cold-temperate species, we examined the phylogeography of a widespread snake species (Vipera berus) inhabiting Europe up to the Arctic Circle. The analysis of the mitochondrial DNA (mtDNA) sequence variation in 1043 bp of the cytochrome b gene and in 918 bp of the noncoding control region was performed with phylogenetic approaches. Our results suggest that both the duplicated control region and cytochrome b evolve at a similar rate in this species. Phylogenetic analysis showed that V. berus is divided into three major mitochondrial lineages, probably resulting from an Italian, a Balkan and a Northern (from France to Russia) refugial area in Eastern Europe, near the Carpathian Mountains. In addition, the Northern clade presents an important substructure, suggesting two sequential colonization events in Europe. First, the continent was colonized from the three main refugial areas mentioned above during the Lower-Mid Pleistocene. Second, recolonization of most of Europe most likely originated from several refugia located outside of the Mediterranean peninsulas (Carpathian region, east of the Carpathians, France and possibly Hungary) during the Mid-Late Pleistocene, while populations within the Italian and Balkan Peninsulas fluctuated only slightly in distribution range, with larger lowland populations during glacial times and with refugial mountain populations during interglacials, as in the present time. The phylogeographical structure revealed in our study suggests complex recolonization dynamics of the European continent by V. berus, characterized by latitudinal as well as altitudinal range shifts, driven by both climatic changes and competition with related species.

  • 81. Vilhunen, Sampsa
    et al.
    Tiira, Katriina
    Laurila, Anssi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Hirvonen, Heikki
    The bold and the variable: Fish with high heterozygosity act recklessly in the vicinity of predators2008Ingår i: Ethology, ISSN 0179-1613, E-ISSN 1439-0310, Vol. 114, nr 1, s. 7-15Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Variation in the innate behavioral response to predation threat is often assumed to reflect genetic differences among the prey individuals. To date, no published results, however, exist that would offer explanation for the origin of this behavioral variation within populations. Using microsatellites as markers, we estimated the genetic variability of juvenile brown trout (Salmo trutta) individuals whose behavior had been individually recorded in a trade-off situation where both predator chemical cues and food were present. Mean overall heterozygosity and the internal relatedness of fish associated significantly with their activity and foraging, so that the genetically more variable individuals showed more risk-prone behavior under predation risk. No association between genetic variability and behavior was found in trials where predator odors were not present. These results were consistent over the three study populations of brown trout with different backgrounds, suggesting that the phenomenon is of general nature in this species. Of the possible mechanisms suggested to enable the existence of the positive association between neutral microsatellite variation and fitness-related trait, the local effect hypothesis gained more support from our data than the general effect hypothesis.

  • 82.
    Vinnersten, Thomas Z. Persson
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Lundström, Jan O.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Schäfer, Martina L.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Petersson, Erik
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Zooekologi.
    Landin, J.
    A six-year study of insect emergence from temporary flooded wetlands in central Sweden, with and without Bti-based mosquito control2010Ingår i: Bulletin of entomological research, ISSN 0007-4853, E-ISSN 1475-2670, Vol. 100, nr 6, s. 715-725Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    In temporary wetlands in the River Dalalven floodplains, recurrent but irregular floods induce massive hatching of the flood-water mosquito Aedes sticticus, which causes enormous nuisance. Flood-water mosquito control using the biological larvicide Bacillus thuringiensis var. israelensis (Bti) was commenced in parts of the floodplains during 2002, and here we report the first six years of full-season monitoring of general insect emergence from temporary wetlands with and without treatment. Emergence traps, which were emptied weekly, were used from May to September each year. A total of 137,153 insects of 13 taxonomic orders were collected. Diptera was highly dominating and especially the sub-order Nematocera with 18 families was a very prominent taxon. Bti-treatment effects were analysed by taxonomic order, by sub-order in Diptera and Hemiptera, and by family for Nematocera and Coleoptera for the whole study period. We found no significant negative effects of Bti treatments on the production of insects by taxonomic order, with the exception of Coleoptera in the long term. However, no significant negative effects were found for the Coleoptera families, neither in the short term nor in the long term. There was no significant negative treatment effect on Nematocera production, neither when analyzed for the whole sub-order nor when analyzed by family. However, abundance of Ceratopogonidae was significantly higher in experimental than in reference wetlands. We conclude that Bti-treatment effects on insect production may be minute in comparison to other environmental factors structuring the insect fauna of the temporary wetlands studied.

  • 83. Wallgren, M.
    et al.
    Skarpe, C.
    Bergström, R.
    Danell, K.
    Bergström, A.
    Jakobsson, T.
    Karlsson, K.
    Strand, Tanja
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Influence of land use on the abundance of wildlife and livestock in the Kalahari, Botswana2009Ingår i: Journal of Arid Environments, ISSN 0140-1963, E-ISSN 1095-922X, Vol. 73, nr 3, s. 314-321Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Human land use such as pastoralism may be a key determinant of wildlife populations. We studied the influence of land use on wildlife and livestock in south-western Kalahari, Botswana, during the wet and dry seasons. We included two types of livestock areas and two types of wildlife protection areas. Wild and domestic mammals >0.2 kg were sampled by distance technique. Small mammals <0.2 kg were trapped and a vegetation survey was performed. Livestock and some medium-sized wildlife species were most abundant in livestock areas, while large-sized wildlife species were mainly restricted to wildlife areas. Most red-listed species were confined to the national park. The influence of land use on abundances changed moderately between seasons. However, cattle moved into wildlife areas during the wet season. Differences in species richness and diversity were most pronounced during the dry season. The trapping frequency of small mammals was highest in the national park. Differences in vegetation structure included sparser field layer and higher cover of an invasive shrub in livestock areas. Our study shows the importance of protected areas for many wildlife species in the Kalahari. It also shows the value of a multi-species approach for investigating the effects of land use on wildlife communities.

  • 84.
    Östman, Örjan
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Drakare, Stina
    Kritzberg, Emma S.
    Langenheder, Silke
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Logue, Jürg Brendan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Lindström, Eva S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Regional invariance among microbial communities2010Ingår i: Ecology Letters, ISSN 1461-023X, E-ISSN 1461-0248, Vol. 13, nr 1, s. 118-127Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Microbial ecology has focused much on causes of between-site variation in community composition. By analysing five data-sets each of aquatic bacteria and phytoplankton, we demonstrated that microbial communities show a large degree of similarity in community composition and that abundant taxa were widespread, a typical pattern for many metazoan metacommunities. The regional abundance of taxa explained on average 85 and 41% of variation in detection frequency and 58 and 31% of variation in local abundances for bacteria and phytoplankton, respectively. However, regional abundance explained less variation in local abundances with increasing environmental variation between sites within data-sets. These findings indicate that the studies of microbial assemblages need to consider similarities between communities to better understand the processes underlying the assembly of microbial communities. Finally, we propose that the degree of regional invariance can be linked to the evolution of microbes and the variation in ecosystem functions performed by microbial communities.

  • 85.
    Östman, Örjan
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Lundström, Jan O.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Vinnersten, Thomas Z. Persson
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution, Populationsbiologi och naturvårdsbiologi.
    Effects of mosquito larvae removal with Bacillus thuringiensis israelensis (Bti) on natural protozoan communities2008Ingår i: Hydrobiologia, ISSN 0018-8158, E-ISSN 1573-5117, Vol. 607, nr 1, s. 231-235Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The protein crystals produced by Bacillus thuringiensis israelensis (Bti) are used against the larvae of pestiferous flood-water mosquitoes in ephemeral wetlands. Although mosquito larvae are considered important predators on protozoans and bacteria, it is not known how a distinct reduction of mosquito larvae density in natural wetlands caused by application of Bti may indirectly affect these microbial communities. Here we show, in a large scale experiment in six natural wetlands, that the densities of heterotrophic protozoans was on an average 4.5 times higher in wetland areas treated with Bti than in control areas. In addition, the taxonomic richness of heterotrophic protozoans increased on an average of 60% in areas with Bti application compared to control areas. The increase in protozoan density and richness was fairly consistent among sites of different wetland habitats. We discuss the potential implications of our results for other parts of the ecosystem.

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