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  • 1. Bommarco, Riccardo
    et al.
    Lönn, Mikael
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Danzer, Ulrika
    Pålsson, Karl-Johan
    Torstensson, Peter
    Genetic and phenotypic differences between thistle populations in response to habitat and weed management practices2010In: Biological Journal of the Linnean Society, ISSN 0024-4066, E-ISSN 1095-8312, Vol. 99, no 4, p. 797-807Article in journal (Refereed)
    Abstract [en]

    Rapid evolutionary change is increasingly being recognized as commonplace, but the evolutionary consequences for species and ecosystems under human-induced selection regimes have not been explored in detail, although many species occur in such environments. In a common garden experiment and with amplified fragment length polymorphism markers, we examined whether genetic differentiation has taken place between spatially intermixed populations of creeping thistles Cirsium arvense (Asteraceae) collected from a natural habitat (maritime shores), a semi-natural habitat (road verges) and arable fields under two management regimes: conventional and organic farming. Populations of C. arvense have altered genetically and locally adapted their growth patterns with changed land use. Although plants from different habitats showed similar total biomass production, shoot and root production was higher for maritime populations, suggesting selection for increased competitive ability. Competitive ability then declined in the order semi-natural, conventional farms and organic farms. Thistles in arable fields may be more selected for tolerance against disturbances from herbicides and mechanical weed control. In addition, early shoot sprouting and genetic analysis showed differentiation between plants originating from conventional farms and farms that were converted to organic 9–30 years ago, suggesting some adaptation to altered crop cultivation practices

  • 2.
    Dumanski, Jan P.
    et al.
    Uppsala University.
    Rasi, Chiara
    Uppsala University.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Davies, Hanna
    Uppsala University.
    Ingelsson, Martin
    Uppsala University.
    Giedraitis, Vilmantas
    Uppsala University.
    Lannfelt, Lars
    Uppsala University.
    Magnusson, Patrik K. E.
    Karolinska Institutet.
    Lindgren, Cecilia M.
    University of Oxford, Oxford, United Kingdom.
    Morris, Andrew P.
    University of Oxford, Oxford, United Kingdom.
    Cesarini, David
    New York University, New York, USA.
    Johannesson, Magnus
    Stockholm School of Economics.
    Janson, Eva Tiensuu
    Uppsala University.
    Lind, Lars
    Uppsala University.
    Pedersen, Nancy L.
    Karolinska Institutet.
    Ingelsson, Erik
    Uppsala Univiversity.
    Forsberg, Lars A.
    Uppsala Univiversity.
    Smoking is associated with mosaic loss of chromosome Y2015In: Cancer Research, ISSN 0008-5472, E-ISSN 1538-7445, Vol. 75, article id 4683Article in journal (Other academic)
  • 3.
    Dumanski, Jan P
    et al.
    Uppsala University.
    Rasi, Chiara
    Uppsala University.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Davies, Hanna
    Uppsala University.
    Ingelsson, Martin
    Uppsala University.
    Giedraitis, Vilmantas
    Uppsala University.
    Lannfelt, Lars
    Uppsala University.
    Magnusson, Patrik K E
    Karolinska Institutet.
    Lindgren, Cecilia M
    Morris, Andrew P
    University of Liverpool, Liverpool, UK..
    Cesarini, David
    New York University, New York, USA..
    Johannesson, Magnus
    Stockholm School of Economics.
    Tiensuu Janson, Eva
    Uppsala University.
    Lind, Lars
    Uppsala University.
    Pedersen, Nancy L
    Karolinska Institutet.
    Ingelsson, Erik
    Uppsala University.
    Forsberg, Lars A
    Uppsala University.
    Smoking is associated with mosaic loss of chromosome Y2015In: Science, ISSN 0036-8075, E-ISSN 1095-9203, Vol. 347, no 6217, p. 81-83Article in journal (Refereed)
    Abstract [en]

    Tobacco smoking is a risk factor for numerous disorders, including cancers affecting organs outside the respiratory tract. Epidemiological data suggest that smoking is a greater risk factor for these cancers in males compared to females. This observation, together with the fact that males have a higher incidence of and mortality from most non-sex-specific cancers, remains unexplained. Loss of chromosome Y (LOY) in blood cells is associated with increased risk of nonhematological tumors. We demonstrate here that smoking is associated with LOY in blood cells in three independent cohorts [TwinGene: odds ratio (OR) = 4.3, 95% CI = 2.8-6.7; ULSAM: OR = 2.4, 95% CI = 1.6-3.6; and PIVUS: OR = 3.5, 95% CI = 1.4-8.4] encompassing a total of 6014 men. The data also suggest that smoking has a transient and dose-dependent mutagenic effect on LOY status. The finding that smoking induces LOY thus links a preventable risk factor with the most common acquired human mutation.

  • 4.
    Elväng, Annelie
    et al.
    Södertörn University, School of Life Sciences, Molecular biology.
    Melik, Wessam
    Södertörn University, School of Life Sciences, Chemistry. Södertörn University, School of Life Sciences, Molecular biology.
    Bertrand, Yann
    Södertörn University, School of Life Sciences, Molecular biology.
    Lönn, Mikael
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Environmental science.
    Johansson, Magnus
    Södertörn University, School of Life Sciences, Chemistry. Södertörn University, School of Life Sciences, International health.
    Sequencing of a Tick-Borne Encephalitis Virus from Ixodes ricinus Reveals a Thermosensitive RNA Switch Significant for Virus Propagation in Ectothermic Arthropods.2011In: Vector Borne and Zoonotic Diseases, ISSN 1530-3667, E-ISSN 1557-7759, Vol. 11, no 6, p. 649-658Article in journal (Refereed)
    Abstract [en]

    Tick-borne encephalitis virus (TBEV) is a flavivirus with major impact on global health. The geographical TBEV distribution is expanding, thus making it pivotal to further characterize the natural virus populations. In this study, we completed the earlier partial sequencing of a TBEV pulled out of a pool of RNA extracted from 115 ticks collected on Torö in the Stockholm archipelago. The total RNA was sufficient for all sequencing of a TBEV genome (Torö-2003), without conventional enrichment procedures such as cell culturing or suckling mice amplification. To our knowledge, this is the first time that the genome of TBEV has been sequenced directly from an arthropod reservoir. The Torö-2003 sequence has been characterized and compared with other TBE viruses. In silico analyses of secondary RNA structures formed by the two untranslated regions revealed a temperature-sensitive structural shift between a closed replicative form and an open AUG accessible form, analogous to a recently described bacterial thermoswitch. Additionally, novel phylogenetic conserved structures were identified in the variable part of the 3'-untranslated region, and their sequence and structure similarity when compared with earlier identified structures suggests an enhancing function on virus replication and translation. We propose that the thermo-switch mechanism may explain the low TBEV prevalence often observed in environmentally sampled ticks. Finally, we were able to detect variations that help in the understanding of virus adaptations to varied environmental temperatures and mammalian hosts through a comparative approach that compares RNA folding dynamics between strains with different mammalian cell passage histories.

  • 5.
    Eriksson, Sofia
    et al.
    Södertörn University, School of Life Sciences, Environmental science. Stockholms universitet.
    Lönn, Mikael
    Södertörn University, School of Life Sciences, Biology.
    Historical perspepctives on landscape representation and forest composition in Woodland Key Habitats compared to formally protected forest in boreal SwedenManuscript (preprint) (Other academic)
    Abstract [en]

    Habitats of Swedish conservation interests are in general small and fragmented following the extensive and intensive forest management history. This study covering 71 000 ha of boreal Sweden investigates how history influences present-day distribution and composition of forests identified as high conservation value habitats and how they are protected. We also investigated if the habitat criteria used to describe reservations differed between reservation types and if habitat criteria were associated with the size of Woodland Key Habitats. The results show strong effects from historical ownership and historical forest type on the probability of an area being set aside as formally protected or as voluntary protected Woodland Key Habitats. We also found that both formal reservations and Woodland Key Habitats primarily cover coniferous forest in the age interval 70-110 years but not the presumably most valuable oldest coniferous category >110 or deciduous forests, which are as common in reservations as in other areas. Old deciduous forests (>110 years) are significantly more rare in formal reservations compared to the forest matrix. When viewed in a context of fragmentation and edge effects the results underline the importance of evaluating reserved areas and Woodland Key Habitats in a wider temporal and larger spatial perspective to optimize conservation management efforts. Maximal representation and biodiversity can be better achieved if new reservations are chosen to represent different ownership and forest history, and if they are selected in a landscape context related to present reservations and the present surrounding production forest.

  • 6.
    Eriksson, Sofia
    et al.
    Södertörn University, School of Life Sciences, Environmental science. Stockholms universitet.
    Lönn, Mikael
    Södertörn University, School of Life Sciences, Biology.
    Interactions between historical forest composition and ownership affect present composition of older forest in boreal SwedenManuscript (preprint) (Other academic)
    Abstract [en]

    In this study we reconstruct forest composition during the 1860s for a 71000 ha area in southern boreal Sweden. The aim is to show how historical ownership and associated anthropogenic disturbances act as a source of heterogeneity in the present-day distribution and composition of coniferous and deciduous forest within the commercial production forest. We use older (>110 years) and mature (70-110 years) forest as response variables in generalized linear models with a binominal error distribution. The explanatory variables include size of zone, historical type of ownership zone (village, company, and farm), amount of forest, and forest type. We focus in particular on investigating effects from interacting explanatory variables. The significant statistical associations in the study indicate that patterns of deciduous and coniferous older patches differ, and that deciduous patches differ in relation to age interval. The oldest deciduous patches, for example, are today more likely on areas that had deciduous cover also in the past and stood on forestland managed by farmers, but less likely on the same habitat managed by companies. We show that there are strong effects on present forest composition from historical ownership and forest composition. We argue that by including local data on past ownership combined with knowledge on use patterns management could be better adapted to local landscape dynamics compared to the application of overly generalized patterns or models of boreal dynamics that excludes interactions with management.

  • 7.
    Eriksson, Sofia
    et al.
    Södertörn University, School of Life Sciences, Environmental science. Stockholm University.
    Skånes, Helle
    Hammer, Monica
    Södertörn University, School of Life Sciences, Environmental science.
    Lönn, Mikael
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Current distribution of older and deciduous forests as legacies from historical use patterns in a Swedish boreal landscape (1725–2007)2010In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 260, no 7, p. 1095-1103Article in journal (Refereed)
    Abstract [en]

    We combine historical maps and satellite derived data to reconstruct the development of a Swedish boreal landscape over the past 300 years. The aim is to understand legacies from past use patterns in present-day forest composition and consequences for conservation objectives from a landscape perspective. We analyze landscape development in cross-tabulation matrixes, building change trajectories. These trajectories are tested in linear models to explain the distribution of present-day landscape composition of coniferous, mixed, and deciduous forests >110 years. Of 49 tested change trajectories, 11 showed a significant association. Associations for mixed and coniferous forests were similar and linked to characteristics such as forest continuity, which characterized the studied landscape. Deciduous older forests did not show any association to forest continuity but were more likely to occur on areas that specifically shifted from forests with grazing in the 1720s to open impediment (likely indicating low tree coverage) in the 1850s. There were large shifts and spatial redistribution in ownerships over time. Use patterns and legacies varied between small- and large-scale ownership categories as well as within small-scale categories. The legacies found in the study indicate a complex origin of heterogeneous landscape elements such as older deciduous forests. Additionally, the origin of the legacies indicates a potential need to diversify conservation management based on the influence of past use patterns. Despite large inconsistencies in historical and contemporary data we argue that this type of analysis could be used to further understand the distribution of landscape elements important for conservation objectives.

  • 8. Grandin, Ulf
    et al.
    Lönn, Mikael
    Södertörn University, Avdelning Naturvetenskap.
    Rydin, Håkan
    Allozyme variation at a PGI locus in differently aged populations of Moehringia trinervia (Caryophyllaceae) in a successional area2002In: Nordic Journal of Botany, ISSN 0107-055X, E-ISSN 1756-1051, Vol. 22, no 3, p. 303-311Article in journal (Refereed)
    Abstract [en]

    We studied genetic effects of the colonisation process during primary succession by analysing allozyme variation at a PGI locus in differently aged populations of Moehringia trinervia, which is a selfing annual with low dispersal ability. The populations studied come from islands and shores created in the 1880s by a drop in the water table of a Swedish lake and from old parts of a large island and of the mainland. The population age is known from five vegetation analyses over a century. We have also analysed the genetic composition of M. trinervia derived from seeds in the soil. Mainland populations had a higher genetic diversity than island populations that were little differentiated and differed genetically from the mainland populations. There was no temporal trend in the distribution of genetic variation on the new islands. The presence of alleles in the extant populations was associated with the proportion of that allele in the seed bank, indicating a main recruitment from the seed bank and not by repeated immigrations. We suggest that some of the new islands were colonised by a few early founders from the mainland. Later colonisation has occurred between adjacent islands, which preserves the founder effect and could explain the uniform, low genetic variation in the island populations

  • 9. Gunnarsson, Urban
    et al.
    Shaw, Jon A.
    Lönn, Mikael
    Södertörn University, School of Life Sciences.
    Local-scale genetic structure in the peatmoss Sphagnum fuscum2007In: Molecular Ecology, ISSN 0962-1083, E-ISSN 1365-294X, Vol. 16, no 2, p. 305-312Article in journal (Refereed)
    Abstract [en]

    Sphagnum (peatmoss) dominates huge areas of the Northern Hemisphere and acts as a significant carbon sink on a global scale, yet little is known about the genetic structure of Sphagnum populations. We investigated genetic structure within a population of the common peatmoss Sphagnum fuscum, to assess local patterns of genetic diversity and the spatial extent of clones. One hundred seventeen shoots were sampled from five transects in Fuglmyra, central Norway, and sequenced for three anonymous DNA regions. Five neighbourhood patches were marked along each transect, and from each patch, five stems were sampled for molecular analyses. Seventeen haplotypes could be distinguished and two major groups of haplotypes differed by 12 mutational steps. The two major haplotype groups differed significantly in microhabitat association along the distance to groundwater table and the pH gradients, indicating microhabitat differentiation. The haplotypes within these groups were all genetically similar, differing by one or two mutations. The most common haplotype occurred in four transects separated by 250-m distance. Most of the molecular variation in the population was found among transects, and within patches. Large dominating clones within each transect resulted in low variation explained by the among-patch-within-transect component of spatial structure. Mutation appears to account for a larger proportion of the population variation than recombination. Within the population, vegetative growth and asexual reproduction from gametophyte fragments dominate as the main reproductive mode

  • 10. Gustafsson, Susanne
    et al.
    Lönn, Mikael
    Södertörn University, Avdelning Naturvetenskap.
    Genetic differentiation and habitat preference of flowering-time variants within Gymnadenia conopsea2003In: Heredity, ISSN 0018-067X, E-ISSN 1365-2540, Vol. 91, p. 284-292Article in journal (Refereed)
    Abstract [en]

    Using fast-evolving microsatellites, more slowly evolving ITS markers and performing habitat analyses, we demonstrated a drastic genetic divergence and significant habitat differentiation between early- and late-flowering variants of plants morphologically belonging to Gymnadenia conopsea ssp conopsea. The two phenological variants can either be found in separate or in mixed populations. Information from microsatellite markers and ITS sequences indicated the occurrence of an early historical split between the two flowering-time variants, a split that has been maintained until the present time even within sympatric populations. Early-flowering variants were also far more genetically diverse, had more alleles per microsatellite locus and a wider habitat amplitude than late-flowering variants. As a comparison, we included G. odoratissima in the sequencing study. We found G. odoratissima to be most closely related to the early-flowering type. This indicates a more ancient divergence event between the two flowering-time variants within G. conopsea ssp conopsea than between the two different species G. odoratissima and the early-flowering variant of G. conopsea. Possible explanations to the results arrived at and possible mechanisms maintaining the genetic separation are discussed.

  • 11. Hanson, K
    et al.
    Lönn, Mikael
    Effekter av hyggesbruk och habitat-egenskaper pa den demografiska strukturen hos populationer av glesgroe Glyceria lithuanica1999In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 93, no 5/6, p. 249-256Article in journal (Other academic)
  • 12.
    Jonsson, Magnus
    et al.
    Södertörn University, School of Life Sciences.
    Bertilsson, Maria
    Ehrlén, Johan
    Lönn, Mikael
    Södertörn University, School of Life Sciences.
    Genetic divergence of climatically marginal populations of Vicia pisiformis on the Scandinavian Peninsula2008In: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 145, no 1, p. 1-8Article in journal (Refereed)
    Abstract [en]

    Vicia pisiformis L. is a perennial leguminous plant with a main distribution in broadleaved forest-steppes of eastern Europe. The species is classified as endangered (EN) according to the IUCN red-lists in both Norway and Sweden, due to severe fragmentation, small population sizes and continuing population decline. The populations on the Scandinavian Peninsula constitute the northern limit of the species distribution and are mostly restricted to warm stony slopes with predominantly southern aspects. In this study we used the AFLP method, which is a high-resolution genetic fingerprint method. Samples were collected from 22 Scandinavian populations. The overall genetic structure was analysed in an AMOVA, in a Mantel test and through constrained correspondence analysis (CCA). The ordination scores representing non-geographic genetic divergence were extracted from the CCA and analysed in a linear model using habitat variables and population size as explanatory variables. We found (i) a strong geographic structure, (ii) significant genetic divergence between populations, (iii) that this genetic divergence remained significant even after removing the effect of geography in a partial CCA and (iv) that the remaining non-geographic part of genetic divergence (distance from the ordination centre) was associated with aspect, populations with a northern aspect were more genetically divergent. Aspect explains more variation than population size and is the only variable retained in the minimal adequate model. We suggest that local adaptation has caused this divergence from an expected geographical pattern of genetic variation. This explanation is further supported by the association between aspect and specific AFLP fragments. Many plant populations are relics of a different climate (Aguirre-Planter et al. 2000; Despres et al. 2002; Pico and Riba 2002). In response to long-term climate change, populations can either migrate towards a more favourable climate or adapt to the new conditions (delaVega 1996; Jump et al. 2006). Species with limited dispersal ability are at risk of reaching isolated dead-ends of decreasingly suitable habitat, without any suitable habitat within dispersal distance (Colas et al. 1997). Isolated populations have to use their inherent evolutionary potential and adapt to changes in environmental conditions, or they will go extinct. As population fragments go extinct, those that remain will become increasingly isolated from each other both spatially and also genetically as the level of gene flow declines with increasing distance. Such correlation between genetic dissimilarities and geographic distances, known as isolation by distance (Slatkin 1993; Wright 1943), when found, suggests a history of geographically limited gene flow (Kimura and Weiss 1964). On top of an isolation by distance pattern there might be other genetic structures to be found. Occasional long-distance dispersal events for example may disturb geographic patterns with puzzling allele distributions as a result (Nichols and Hewitt 1994). Genetic drift is a process that will affect any pattern of genetic variation in a random fashion. Local adaptation through natural selection is a process that, if sufficiently strong in comparison with gene flow and genetic drift, will create patterns where genetic differentiation is associated with certain environmental conditions (Wright 1951). Several studies have shown the importance of local adaptation of populations (reviewed by Kawecki and Ebert 2004) (see also Bonin et al. 2006; Knight and Miller 2004; Kolseth and Lönn 2005; Lönn et al. 1998). Local adaptation can be strong also at small spatial scales (Snaydon and Davies 1976; Lönn 1993) even though it is sometimes very limited in terms of the number of genes involved (Kärkkainen et al. 2004) Environmental variability provides a base for biological variation by imposing differentiated selection pressures resulting in local adaptation. Topography provides large environmental variation within a relatively small area and thereby provides a basis for small-scale local adaptations. Depending on the local topographic possibilities populations can either migrate up and down slopes or along the same altitude to a different aspect to find a suitable microclimate. The dispersal distance will be much shorter per degree of temperature change during altitudinal migration (Hewitt 1996), than during simple latitudinal migration across a flat landscape. Slope and aspect are two important topographic parameters that determine the influx level of solar radiation, especially towards the poles where the total global radiation decreases (Larcher 2003). Vicia pisiformis is an endangered poorly-dispersed long-lived forest herb with its main distribution across the semi-open broadleaved forest steppes of eastern Europe. The Scandinavian populations are believed to be climate relict populations from warmer times. Earlier genetic studies of V. pisiformis using allozymes, RAPD:s and morhology, have found low to very low levels of genetic variation (Gustafsson and Gustafsson 1994; Black-Samuelsson et al. 1997; Black-Samuelsson and Lascoux 1999). Therefore we used AFLP (amplified fragment length polymorphism) markers, which detect even very small genetic differences between individuals. AFLP mainly analyse neutral variation, as the major fraction of most genomes is assumed to be neutral. However, since the AFLP-fragments are distributed randomly throughout the whole genome some fragments may be situated so close to regions under selection that they become more or less linked to them. This linkage disequilibrium between molecular markers and regions under selection, often referred to as quantitative trait loci (QTL), forms the basis for both QTL-mapping and marker assisted selection (MAS), reviewed by Dekkers and Hospital (2002). Gardner and Latta (2006) for example, found QTL under selection in both natural environments and in the greenhouse. Markers have been found to be connected to biomass production (Cavagnaro et al. 2006) and environmental variation (Bonin et al. 2006; Jump et al. 2006; Porcher et al. 2006). In this study we examine 22 Swedish and Norwegian populations of Vicia pisiformis and ask (i) if there is genetic differentiation between these populations, (ii) if there is can it be explained in its entirety by geographic location or (iii) can it partly be explained by habitat characteristics, suggesting local adaptation, or population size, suggesting genetic drift. We show that populations are differentiated geographically and that genetic variation in addition to the geographical pattern is associated with habitat.

  • 13.
    Kolseth, Anna-Karin
    et al.
    Södertörn University, School of Life Sciences.
    Lönn, Mikael
    Södertörn University, School of Life Sciences.
    Genetic structure of Euphrasia stricta on the Baltic island of Gotland, Sweden2005In: Ecography, ISSN 0906-7590, E-ISSN 1600-0587, Vol. 28, no 4, p. 443-452Article in journal (Refereed)
    Abstract [en]

    Genetic differentiation between and within five varieties of Euphrasia stricta (var. brevipila, var. gotlandica, var. stricta, var. suecica and var. tenuis) on Gotland was investigated, using amplified fragment length polymorphism, AFLP. The varieties are described in the literature by morphology and association to habitat type. We wanted to investigate whether the varieties are locally adapted populations to the typical habitat type for each variety or if they are preadapted to certain habitat types and have colonized Gotland in their present form. A constrained principal coordinate analysis revealed three genetically differentiated subunits within the species. The two early-flowering varieties suecica and tenuis each formed a distinct group, while the three late-flowering varieties brevipila, gotlandica and stricta together formed the third group. A phylogenetic tree confirms the partitioning into three groups. Within the group containing the late-flowering varieties there are populations that pair as each other's closest relatives, but belong to different varieties. These pairs are also geographically adjacent. The phylogenetic tree had a “star-like” appearance indicating a stronger divergence between populations than between varieties. The same pattern was seen in the partitioning of genetic diversity, with a lower amount of genetic variation occurring between varieties, FST=0.14, than between populations within the varieties, FST ranging from 0.26 to 0.60. In Euphrasia stricta the varieties suecica and tenuis and the group containing the varieties stricta/gotlandica/brevipila are likely to have a phylogeographical history outside Gotland, or an ancient and concealed local origin on the island. Within the group stricta/gotlandica/brevipila local evolutionary events seem to determine the variety identity, probably through local adaptation. Natural selection, genetic drift and mutations create genetic differentiation between populations. Gene flow, on the other hand, may counteract these processes (Slatkin 1987). Local adaptation is affected by the stability and strength of the natural selection and the amount of gene flow (Rice and Mack 1991, van Tienderen 1992, Miller and Fowler 1994), but also by the amount of genetic variability for the character that selection works on (Dudley 1996). Many studies have been done in the area of local adaptation (Lönn 1993, Prentice et al. 1995, Lönn et al. 1996, Liviero et al. 2002), and some studies have identified selective agents causing the adaptations. The selective agents are for example small differences in ecological niches and frequency dependent selection caused by pathogens (Parker 1994) or differences in selection regimes in different habitats (Kittelson and Maron 2001). Recent findings on ecological speciation emphasizes the importance of niche-shifting in local populations or groups of populations (Levin 2003) and rapid accumulation of beneficial mutations in isolated small populations (Rieseberg et al. 2003). Evolution works on different spatial and temporal scales, which makes it important to consider these different scales when studying evolutionary processes. Looking at the local phylogeny, geographic and temporal aspects are important when they link evolutionary processes to the extant landscape and the properties of the genetic structure. Linking evolutionary processes to the extant landscape is an important tool in evaluating evolutionary potential and predicting effects of landscape changes. Regional dynamics within species, using varieties/ecotypes, may also give information on initiation of speciation events. Manel et al. (2003) introduce and define landscape genetics as the combination of molecular population genetics and landscape ecology. The advantage of landscape genetics is the combination of the broad geographical span of scales (landscape to microclimate) and the high genetic resolution (individuals) compared to biogeography and phylogeography, which focuses more on species level at a broad spatial and temporal scale. Escudero et al. (2003), like Manel et al. (2003), put an emphasis on the spatial analysis of genetic diversity where a second step is to find ecological or demographic processes that could have shaped the genetic structure. A more direct approach is to measure habitat and genetic properties at many geographic locations and then model the biological processes shaping the spatial genetic structure (Lönn 1993, Prentice et al. 1995), which is the approach we intend to follow here. Molecular markers will be able to trace stochastic processes like drift and gene-flow (Page and Holmes 1998) as well as selective events through hitch-hiking (Hedrick 1980) and linkage events: AFLP has been used to identify quantitative trait loci by Via and Hawthorne (2002) and to explore the role of directional selection in whitefish ecotypes by Campbell and Bernatchez (2004). Yeo (1954, 1956, 1961, 1962, 1964, 1966, 1968) has done an extensive study of the cytology, hybridisation, cultivation, germination and relationship between species of British and European Euphrasia species. Yeo (1968) concludes that differences in chromosome number, habitat preferences and spatial distribution drives the speciation of Euphrasia in Europe and limits the hybridisation between species. The hybridisation may however result in new gene combinations for selection to work on (Yeo 1968). Yeo (1968) suggests that Euphrasia has gone through a fast and quite recent evolution in Europe after the last glaciation since Euphrasia has interfertile species of which many are endemic to small areas. Today, species differentiation within Euphrasia may be due to vegetation history, hybridisation and the parallel selection of well-adapted biotypes in similar or identical habitats (Karlsson 1976). Both Karlsson (1986) and Yeo (1968) put emphasis on the habitat specialization as an important factor in speciation referring to high morphological variability and hybridisation creating possibilities to evolve habitat specializations in Euphrasia.Zopfi (1998) showed in cultivation experiments that there is a genetic basis for different ecotypic variants of Euphrasiarostkoviana defined by grassland management, concerning onset of flowering, seed size and flowering period, life-history characters that are important adaptations to grazing and mowing. Euphrasia stricta is a tetraploid annual hemiparasite belonging to the Scrophulariaceae family (Yeo 1968, Krok and Almquist 2001). The species occurs all over Europe, except on the British Isles and in Spain and Portugal (Hultén and Fries 1986). In Sweden five varieties are found, which are subdivided based on morphology, phenology and habitat preference (Krok and Almquist 2001). They all grow on the Baltic island of Gotland, which is situated east of Sweden consisting of Silurian limestone (Fredén 1994). Euphrasia stricta var. suecica and E. stricta var. tenuis grow in traditionally managed wooded hay meadows and both are early flowering (Karlsson 1984). The variety suecica is red-listed according to the Swedish Red List (Gärdenfors 2000) and exists only in meadows on Gotland. The variety tenuis exists not only on Gotland but also on the Swedish mainland although it is declining throughout its distribution range. The populations of suecica and tenuis on Gotland are well known (Karlsson 1984, Petersson 1999). Euphrasia stricta var. stricta and E. stricta var. brevipila occur in pastures, along paths and on cultivated land. They flower later in the summer than var. suecica and var. tenuis. The variety stricta is common on the calcareous ground on Gotland with short grass turf, but rare on the mainland in contrast to the variety brevipila, which is common in whole of Sweden except on Gotland. The variety brevipila prefers soils that contain more sand compared to stricta. The late-flowering variety gotlandica is only found on Gotland and Öland, the second Baltic island on the Swedish east coast, were it is restricted to temporary pools on limestone ground (alvar) (Karlsson 1986). All Euphrasia species seems to lack a persistent seed bank (Karlsson 1984), but seeds have survived for up to three years in pots in cultivation experiments of other Euphrasia species (Yeo 1961). Artificial selfing and crosses within and between populations of Euphrasia stricta var. stricta yield high fertility in progeny pollen, 70–100% in between population crosses and 90–100% in selfing or within population crosses (Karlsson 1986). Flowering time for Euphrasia is not only dependent on habitat, but also to some extent on temperature and host attachment (Wilkins 1963, Yeo 1964, Molau 1993, Svensson et al. 2001, Svensson and Carlsson 2004). Euphrasia stricta probably have a mixed mating system (von Wettstein 1896). Based on these factors, which separates the varieties spatially and temporal, the aim of this study was to examine whether the varieties are locally adapted ecotypes that have evolved more than one time on the studied geographical scale or if they are distinct units over the region, implying colonization from outside or a single evolutionary event

  • 14.
    Kolseth, Anna-Karin
    et al.
    Södertörn University, School of Life Sciences. Uppsala universitet.
    Lönn, Mikael
    Södertörn University, School of Life Sciences.
    Habitat Associations of Fine-scale Genetic Structure in an Euphrasia stricta PopulationManuscript (preprint) (Other academic)
  • 15.
    Kolseth, Anna-Karin
    et al.
    Södertörn University, School of Life Sciences. Uppsala universitet.
    Lönn, Mikael
    Södertörn University, School of Life Sciences.
    Regional Genetic Structure in the Tetraploid Hemiparasite Euphrasia stricta Inferred from MicrosatellitesManuscript (preprint) (Other academic)
  • 16.
    Kolseth, Anna-Karin
    et al.
    Södertörn University, School of Life Sciences. Uppsala University.
    Lönn, Mikael
    Södertörn University, School of Life Sciences.
    Svensson, Brita M.
    Genetic structure in two meadow varieties of Euphrasia stricta on the Baltic island of Gotland (Sweden) and implications for conservation2005In: Folia Geobotanica, ISSN 1211-9520, E-ISSN 1874-9348, Vol. 40, no 2-3, p. 163-176Article in journal (Refereed)
  • 17.
    Larsson, Josefine
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Lind, E. E.
    SLU.
    Corell, H.
    Göteborgs universitet.
    Grahn, Mats
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Smolarz, K.
    University of Gdańsk, Gdynia, Poland.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Mathematics Teaching.
    Regional genetic differentiation in the blue mussel from the Baltic Sea area2017In: Estuarine, Coastal and Shelf Science, ISSN 0272-7714, E-ISSN 1096-0015, p. 98-109Article in journal (Refereed)
    Abstract [en]

    Connectivity plays an important role in shaping the genetic structure and in evolution of local adaptation. In the marine environment barriers to gene flow are in most cases caused by gradients in environmental factors, ocean circulation and/or larval behavior. Despite the long pelagic larval stages, with high potential for dispersal many marine organisms have been shown to have a fine scale genetic structuring. In this study, by using a combination of high-resolution genetic markers, species hybridization data and biophysical modeling we can present a comprehensive picture of the evolutionary landscape for a keystone species in the Baltic Sea, the blue mussel. We identified distinct genetic differentiation between the West Coast, Baltic Proper and Bothnian Sea regions, with lower gene diversity in the Bothnian Sea. Oceanographic connectivity together with salinity and to some extent species identity provides explanations for the genetic differentiation between the West Coast and the Baltic Sea (Baltic Proper and Bothnian Sea). The genetic differentiation between the Baltic Proper and Bothnian Sea cannot be directly explained by oceanographic connectivity, species identity or salinity, while the lower connectivity to the Bothnian Sea may explain the lower gene diversity. © 2016.

  • 18.
    Larsson, Josefine
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Lind, Emma E
    SLU.
    Świeżak, Justyna
    University of Gdansk, Gdynia , Poland.
    Smolarz, Katarzyna
    University of Gdansk, Gdynia , Poland.
    Grahn, Mats
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Sewage treatment plant associated genetic differentiation in the blue mussel from the Baltic Sea and Swedish west coast2016In: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, Vol. 4, article id e2628Article in journal (Refereed)
    Abstract [en]

    Human-derived environmental pollutants and nutrients that reach the aquatic environment through sewage effluents, agricultural and industrial processes are constantly contributing to environmental changes that serve as drivers for adaptive responses and evolutionary changes in many taxa. In this study, we examined how two types of point sources of aquatic environmental pollution, harbors and sewage treatment plants, affect gene diversity and genetic differentiation in the blue mussel in the Baltic Sea area and off the Swedish west coast (Skagerrak). Reference sites (REF) were geographically paired with sites from sewage treatments plant (STP) and harbors (HAR) with a nested sampling scheme, and genetic differentiation was evaluated using a high-resolution marker amplified fragment length polymorphism (AFLP). This study showed that genetic composition in the Baltic Sea blue mussel was associated with exposure to sewage treatment plant effluents. In addition, mussel populations from harbors were genetically divergent, in contrast to the sewage treatment plant populations, suggesting that there is an effect of pollution from harbors but that the direction is divergent and site specific, while the pollution effect from sewage treatment plants on the genetic composition of blue mussel populations acts in the same direction in the investigated sites.

  • 19.
    Lönn, Mikael
    et al.
    Södertörn University, School of Life Sciences.
    Alexandersson, Ronny
    Gustafsson, Susanne
    Hybrids and fruit set in a mixed flowering-time population of Gymnadenia conopsea (Orchidaceae).2006In: Hereditas, ISSN 0018-0661, E-ISSN 1601-5223, Vol. 143, p. 222-228Article in journal (Refereed)
    Abstract [en]

    We have recently found that the morphologically determined subspecies Gymnadenia conopsea ssp conopsea in Sweden includes early and late flowering individuals. We were interested in the interactions between the flowering time groups; if there were gene flow between them and if so this was detrimental or advantageous. A spatially mixed population of early and late flowering individuals was studied using three microsatellite loci. We measured patterns in genetic differentiation and inferred occurrence of hybridisation and introgression. Variation in flowering time, fertility and relative and absolute fruit set was measured. The pattern of introgression between flowering-time groups differed between loci. In two of the three investigated loci, allele separation was distinct between early and late flowering plants and one genetically obvious hybrid was infertile. In the third locus, several alleles were shared between the two flowering time variants. The degree of introgression was associated to fruit set failure, which was higher in the late flowering plants and lower in early flowering plants. A small group of early flowering individuals with somewhat delayed flowering compared to the main group was genetically distinct and had lower relative and absolute fruit set. This group was not genetically intermediate, but rather constituting an independent group, with lower fruit set possibly caused by absence of pollinators. There seem to be a strong barrier against introgression into the late flowering group which is kept genetically distinct and less diverse. The early flowering group is diverse, includes two subgroups and seems to benefit from gene flow

  • 20.
    Lönn, Mikael
    et al.
    Södertörn University, School of Life Sciences.
    Andersson, Anna-Carin
    Andersson, Stefan
    Genetisk variation hos vilda växter och djur i Sverige: En kunskapsöversikt om svenska arter och populationer, teori och undersökningsmetoder2007Report (Other (popular science, discussion, etc.))
  • 21.
    Lönn, Mikael
    et al.
    Södertörn University, School of Life Sciences.
    Lundqvist, Anna-Carin
    Andersson, Stefan
    Genetic variation in wild plants and animals in Sweden: A review of case studies from the perspective of conservation genetics2008Report (Other (popular science, discussion, etc.))
  • 22.
    Lönn, Mikael
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Mutvei, Ann
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Mattsson, Jan-Eric
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Results and Comparison of Different Complementary Assessment Methods of Science Learning Outcome2015In: Conference proceedings. New perspectives in science education, 4th ed., Libreriauniversitaria.it , 2015, p. -5Conference paper (Refereed)
    Abstract [en]

    To assess the quality of different aspects of the learning outcomes in relation to knowledge requirements as results of teaching several assessment methods have to be used. For most teachers it is also obvious that students differ in their ability to demonstrate the learning outcome depending on the assessment method used. In order to compare different assessment methods of the learning outcome of pre-school teacher students’ different types of tasks were evaluated and compared in order to identify the potential of each method to give the students fair chances of showing their skills. Thus, assessments based on multiple choice questionnaires of different types, long answer questions, practical laboratory experiments, experiment construction and the students ability to evaluate experiment plans were compared. Having Swedish as mother tongue also was included as an explanatory variable since we suspected that some of the assessment methods in reality rather evaluates the linguistic skills in interpreting texts rather than evaluating the content knowledge of the subject. The results for each student when different methods were used were compared in order to evaluate if some of the methods for assessment gave similar results or if the methods induced differences in the results for the same student. We use ordination techniques to assess and visualize main trends in the data and linear models and classification trees to evaluate specific associations. There is correlation between results from several assessment methods, there are positive correlation between combinations of results from long answers, experiment and experiment construction, meaning students who showed good results with one method did so also with the others - but in some comparisons like long answer questions and multiple choice questions good results were independent of each other. There was a negative effect of having a non-Swedish mother tongue on the results in multiple choice questionnaires, but a positive effect of a non-Swedish mother tongue on the combined scores on experimental construction and experiment. Linear models show that good achievements in experimental construction are explained by high summed scores of Doll´s criteria, the four R’s richness, recursion, relations, and rigor.

  • 23.
    Lönn, Mikael
    et al.
    Södertörn University, Avdelning Naturvetenskap.
    Prentice, Honor C.
    Gene diversity and demographic turnover in central and peripheral populations of the perennial herb, Gypsophila fastigiata2002In: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 99, no 3, p. 489-498Article in journal (Refereed)
    Abstract [en]

    Within-population gene diversity (HS) was estimated (using allozyme markers) for 16 populations of the perennial, outcrossing plant, Gypsophila fastigiata, on the Baltic island of Öland. The populations were characterized by data on extent, density, life-stages, and habitat diversity. Populations were classed as central or peripheral in relation to the distribution of “alvar” (habitats with shallow, calcareous soils on limestone bedrock) on southern Öland. Three minimal adequate models were used to explain HS and the proportions of juveniles and dead adults. In the first model, HS was significantly lower in peripheral populations and there were no significant additional effects of other explanatory variables. The lower diversity in peripheral populations can be explained by a combination of genetic drift (in populations that vary in size in response to habitat fragmentation) and lower levels of interpopulation gene flow than in central populations. In the two life-stage models, peripheral populations had significantly larger proportions of both juveniles and dead adults – indicating a greater demographic turnover than in the central populations. There were also significant effects of HS and species diversity on the proportion of juveniles. The central or peripheral position of populations is the strongest predictor of both within-population gene diversity and life-stage dynamics in Öland G. fastigiata.

  • 24.
    Mattsson, Jan-Eric
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Mathematics Teaching.
    Mutvei, Ann
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Mathematics Teaching.
    Art studies as tools for understanding observations in science2017In: Conference proceedings New perspectives in science education: 6th Conference Edition: Florence, Italy: 16-17 March 2017, Limena: Libreriauniversitaria.it , 2017, p. 513-516Conference paper (Refereed)
    Abstract [en]

    Observations are fundamental in science as they has to include cognitive activities based on the perceived sensations. These activities have to be transformed to written or spoken language. In order to practice and visualize these processes we present a method based on Roland Barthes concepts studium and punctum. About 60 students aiming at becoming primary school teachers (years 4–6) were followed during a period of the first two years of their education. The results on all course examinations during these years (n=17) were compared to the quality of two reflective texts. One from the end of the first year on the impression of art works by David Hockney or Bill Viola, another of experiences from field sites used at the beginning of their studies. They wrote reflections on their experiences including observations and their personal and professional development during their teacher training. The texts where analysed by using the 4 R’s of Doll’s. Results of VARK tests assessing the learning style of the students from the beginning of their education were used. The choice of science courses can be shown to be correlated to different factors depending of the selection of these but there was no general pattern behind the choice of science. Training of observation in different contexts and reflections on these in relation to personal development seem to promote better professional understanding.

  • 25.
    Mattsson, Jan-Eric
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Mathematics Teaching.
    Mutvei, Ann
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Mathematics Teaching.
    To communicate the theory of evolution to all from babies to adults2017In: Conexão Ciencia, ISSN 1980-7058, Vol. 12, no 2, p. 408-415Article in journal (Refereed)
    Abstract [en]

    Teaching evolution is a tricky business. Less teaching seems to give better understanding of the theory. Evolutionary processes are dialectic relations between many actors, individuals, groups, abiotic and biotic factors etc., different from mechanistic descriptions of relations between singular objects in other scientific theories. This difference, in combination with religious beliefs confuses efforts to get understanding and acceptance of the theory of evolution. With the new curriculum for Swedish compulsory school, science education has to be linked to students’ own experiences in order to promote critical thinking and skills useable in daily life. Further, biology in science teaching during the first school years is focused on general observations and fundamental concepts, not on scientific methods and evolutionary processes. Thus, students often experience biology as a subject filled with facts about simple relations and teleological explanations, making the theory of evolution superfluous. The objectives here were to design teaching in evolutionary theory adapted to the professional needs of students and to assess the learning outcome. Three different courses in evolutionary theory were included. Two pre-service teacher training programs, for nursery school and for year 4–6 in the compulsory school, and one for students in environmental studies were included. Assessments of learning outcome were made by analyses of texts written by the students. The quality of the science knowledge content and the personal and professional development were assessed by using the 4 R’s of Doll. Associations between concepts and understanding were evaluated using clustering and ordination statistical techniques. The learning outcome was good showing visible progressions in the understanding. Thus, it is important to assess the understanding of concepts rather than estimating their frequency in students texts.

  • 26.
    Mattsson, Jan-Eric
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Mutvei, Ann
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Students´ Different Strategies in their Development of Knowledge, Understanding, and Skills in Science Education2015In: Conference proceedings. New perspectives in science education, 4th ed., Libreriauniversitaria.it , 2015, p. -4Conference paper (Refereed)
    Abstract [en]

    Students differ in their ways of accomplishing varied forms of knowledge, develop personal understanding and improve their skills. Likewise, teachers differ in their way of teaching depending on earlier experiences and training, thus, for teachers it is important understand the different strategies of the students and their own pedagogic profile in order to design learning situations advantageous for all students.

    In this study we try to describe the development and the persistence of the learning outcome of five pre-service primary school teacher students and their teachers during one semester of science and technology teaching. The assessment of the students’ fulfilment of the knowledge requirements was made during and shortly after the course, all of them passed. The focus here is to analyse the students and teachers different routes to achieve professional skills and was made eight months after the finished course. The students and the teachers met and discussed their experiences of their development during the course. The discussions in the whole group and in smaller subgroups were recorded and analysed. One area of interest was to describe the personal and professional development during that semester and how this was regarded retrospectively. This may be regarded as an assessment of the pedagogic activities and their relevance for the different students.

    Another important objective was to describe the conceptual development of both the students and their teachers and to investigate if there were differences in their development. The development of the conceptual profiles of each person was constructed out of the discussions analysed to reveal developmental changes. The conceptual profiles were regarded to contain three basic zones, externalism, internalism and relational.

    A third objective was to investigate the quality of the development out of the criteria of Doll, the four R’s richness, recursion, relations, and rigor and to what extent these criteria were visible in the conceptual development?

    On the professional and personal level all participants recognized a development, for the students supported by experiences during practical training at schools. The result also show that type of conceptual development varied between participants but large similarities in the degree of conceptual development of different concepts in one person. Finally, many of the generative phases of conceptual development were correlated to Doll’s criteria of quality in teaching and learning.

  • 27.
    Mattsson, Jan-Eric
    et al.
    Södertörn University, School of Life Sciences, Biology.
    Vinter, Tiina
    Södertörn University, School of Life Sciences.
    Lönn, Mikael
    Södertörn University, School of Life Sciences.
    Macrolichen diversity in relation to diversity of woody plants2006Conference paper (Other academic)
    Abstract [en]

    In studies concerning nature conservation issues common lichen species have usually been neglected although collecting of these results gives comparatively small disturbance of the populations and is easily done. Instead rare or threatened species or species usually have been used as indicators of sites with high biodiversity. Here, the macrolichen diversity is compared with the diversity of woody plants and other characteristics of different sites in Estonia, Finland and Sweden as a part of a larger project including comparative studies on habitats with presumably high species diversity The site selection was based on the occurrence of Daphne mezereum which usually occurs in semi-open habitats in transitions zones containing species from the surrounding biotopes. One of the main objectives with the study was to develop a fairly rapid method of evaluation of biodiversity using easily identified species. As total inventories are time consuming and reflects snapshots of a certain occasion it is beneficial to use other methods which may give a little less but sufficient information for many purposes, e.g., estimations on biodiversity. The ecological and evolutionary processes that shape diversity and distributions are general and results are assumed to be translatable from the target species to other species. The combination of data from a small number of species may constitute a useful monitoring protocol for lichens and higher plants. In total about 50 lichen species and 25 substrates are included and analyzed in the study. Most of the most common lichens are sorediate or isidiate and asexually reproducing and occur on several substrates. The relation between the diversity of lichen and woody plants is presented.

  • 28.
    Mutvei, Ann
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Mathematics Teaching.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Mathematics Teaching.
    Mattsson, Jan-Eric
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Digestion as an example of integrated teaching of chemistry and biology2017In: Conexão Ciencia, ISSN 1980-7058, Vol. 12, no 2, p. 89-95Article in journal (Refereed)
    Abstract [en]

    Most people are uncertain about how nutrients enter and are distributed in the body. They may be capable of naming the different parts of the digestive system on a torso but have vague ideas of the relation between these organs and the chemical processes they govern. Reasons for this are poor understanding of gas exchange, the role of the circulatory system, and that most processes are intracellular. In order to create a more holistic view of the biology and chemistry of digestion these subjects may be taught simultaneously and integrated. Here practical exercises and lectures about digestion and nutrients for pre-service primary school teachers are presented. The practical work included food preparation in order to investigate the change of the properties of the macromolecules of nutrients. A simple drawing of a body was used in order to visualize the routes of nutrients and the role of gas exchange in digestion. An evolutionary perspective on digestion was used in order to explain the ancient origin of most chemical processes in the digestive system and in the whole body. The material produced by the students at their final examinations was used for assessing their use and understanding of concepts, the quality based on Doll’s 4R’s and the degree of holistic understanding of the digestive system. The findings show that the pedagogic design used gives a general picture of digestion and energy transfer usable for teaching in primary school.

  • 29.
    Mutvei, Ann
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Mattsson, Jan-Eric
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Observation not only perception but also cognition2016In: Conference proceedings: New perspectives in science education : 5th conference edition : Florence, Italy, 17-18 March 2016, Padova: Libreria Universitaria, 2016, p. 365-369Conference paper (Refereed)
    Abstract [en]

    According to the Swedish curriculum for primary school it is important in science subjects to develop skills to observe, to describe the observations and to put them into a theoretical framework already starting year 1–3.

    Thus, it may be important for the teacher not only to be accustomed to the methods of observing but also to be an expert on using these observations in order to design teaching situations where these skills may be developed.

    Here we present a study where 25 pre-service primary school teacher students at the beginning of a 20 weeks course established a relation to a study site focused on ecological questions. The task during the first week of that course was to observe and describe two habitats in the field and suggest what abiotic and biotic factors that had shaped the variation focussing at competition as an important ecological factor. In order to connect those ecological aspects with evolutionary aspects, specimen of the common species in the two habitats were collected and brought to the lab where the students constructed phenetic trees based on morphology but also on ecologically relevant properties like roots/no roots, expecting the set-up to awake evolutionary reflection. A main goal with this week was to give the students tools to investigate nature – to observe and describe patterns and to explain them by observing abiotic and biotic variation and evolutionary features and limitations.

    Later during the course we created other, often not obviously similar, situations where the students had the opportunity to use the experiences of this first training week. We used open questions for reflections and examinations in order to get written material to assess the development of the skills.

    We found notable personal development in most students and a greater awareness about the importance of personal cognitive activities in order to create better understanding and ability to use achieved knowledge in different situations.

  • 30.
    Mutvei, Ann
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Mathematics Teaching.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Mathematics Teaching.
    Mattsson, Jan-Eric
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Biology.
    Technology in preschool: from idea to product2017In: Conference proceedings New perspectives in science education: 6th Conference Edition: Florence, Italy: 16-17 March 2017, Limena: Libreriauniversitaria.it , 2017, p. 604-609Conference paper (Refereed)
    Abstract [en]

    Teaching pre-service preschool teachers in technology is a challenge. Technology is a fairly new subject in school, students lack experiences and are not aware of the aim of the subject. In addition technology also include the consequences of technological choices for individuals, society and environment. The curriculum for pre-school in Sweden emphasize development of children´s knowledge in science, technology and their ability to identify technology in everyday life. The education of pre-service teachers involves visualization of their own tacit knowledge and experiences to be used in the teaching of technology. Here a course during a three weeks period with 55 pre-service teacher students is presented. They worked in groups with construction exercises, museum visit and outdoor technology walk. The students wrote summaries of the processes together with critical reflections. The written exams on the identification of technology in everyday life were analysed by using the quality markers 4R’s of Doll’s and compared with marks on their examination tasks. Our results show that many students could describe the processes of construction with high quality showing several perspectives of understanding, e.g., the advantage of group activity, their own development of understanding and how to teach children in preschool.

  • 31.
    Prentice, Honor C
    et al.
    Department of Biology, Lund University.
    Li, Yuan
    Department of Biology, Lund University.
    Lönn, Mikael
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Tunlid, Anders
    Department of Biology, Lund University.
    Ghatnekar, Lena
    Department of Biology, Lund University.
    A horizontally transferred nuclear gene is associated with microhabitat variation in a natural plant population2015In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 282, no 1821, article id 20152453Article in journal (Refereed)
    Abstract [en]

    Horizontal gene transfer involves the non-sexual interspecific transmission of genetic material. Even if they are initially functional, horizontally transferred genes are expected to deteriorate into non-expressed pseudogenes, unless they become adaptively relevant in the recipient organism. However, little is known about the distributions of natural transgenes within wild species or the adaptive significance of natural transgenes within wild populations. Here, we examine the distribution of a natural plant-to-plant nuclear transgene in relation to environmental variation within a wild population. Festuca ovina is polymorphic for an extra (second) expressed copy of the nuclear gene (PgiC) encoding cytosolic phosphoglucose isomerase, with the extra PgiC locus having been acquired horizontally from the distantly related grass genus Poa. We investigated variation at PgiC in samples of F. ovina from a fine-scale, repeating patchwork of grassland microhabitats, replicated within spatially separated sites. Even after accounting for spatial effects, the distributions of F. ovina individuals carrying the additional PgiC locus, and one of the enzyme products encoded by the locus, are significantly associated with fine-scale habitat variation. Our results suggest that the PgiC transgene contributes, together with the unlinked 'native' PgiC locus, to local adaptation to a fine-scale mosaic of edaphic and biotic grassland microhabitats.

  • 32. Prentice, Honor C.
    et al.
    Lönn, Mikael
    Lager, Helena
    Rosen, Ejvind
    Van Der Maarel, Eddy
    Changes in allozyme frequencies in Festuca ovina populations after a 9-year nutrient/water experiment2000In: Journal of Ecology, ISSN 0022-0477, E-ISSN 1365-2745, Vol. 88, no 2, p. 331-347Article in journal (Refereed)
    Abstract [en]

    1 The grass Festuca ovina is an important constituent of the species-rich 'alvar' grasslands on the Baltic island of Oland. Levels of allozyme polymorphism are high and variation is known to be correlated with habitat variation (soil moisture, pH and depth). 2 A 9-year field experiment on species diversity provided replicate plots (in three sites) that had been subjected to six different experimental treatments (control; N + P + K; P + K; N + K; K; water). 3 Samples of F. ovina were collected and analyses of deviance were used to investigate associations between allele frequencies, at each of four polymorphic loci, and the nutrient/water treatments. We also used the models to estimate predicted values for the alleles in different nutrient/water treatments and in interactions involving the nutrient/water treatments and additional explanatory variables (vegetation height and clipping). 4 There were significant allozyme frequency differences between samples of F. ovina from the six different nutrient/water treatments in the grassland experiment. Frequencies in the fertilized or watered plots had diverged from those in the control plots. There were also significant allele-habitat associations (after the removal of site effects), especially at the Pgi-2 locus. 5 Soil moisture was the only variable that was common to this study and an earlier study of variation in F. ovina in natural habitats. In natural populations, the Pgi-2-2 allele was significantly associated with soil moisture and was more common in dry habitats. Our findings that the frequency of the Pgi-2-2 allele was significantly affected by the nutrient/water treatments, and that it was rarest in the treatment that involved the addition of extra water, were therefore as predicted. 6 The study supports the conclusion, from an earlier study of populations in unmanipulated grassland habitats, that selection is contributing to the fine-scale patterning of genetic variation in the alvar populations of F. ovina.

  • 33. Prentice, Honor C.
    et al.
    Lönn, Mikael
    Södertörn University, School of Life Sciences.
    Rosquist, Gabrielle
    Ihse, Margareta
    Kindström, Merit
    Gene diversity in a fragmented population of Briza media: grassland continuity in a landscape context2006In: Journal of Ecology, ISSN 0022-0477, E-ISSN 1365-2745, Vol. 94, no 1, p. 87-97Article in journal (Refereed)
    Abstract [en]

    1. We investigated patterns of allozyme variation in demes of the grass Briza media in semi-natural grassland fragments within a mosaic agricultural landscape on the Baltic island of Öland. In the study area, Briza is both a characteristic species of old pastures and an early colonizer of young grasslands developing on previously forested or arable sites. 2 Generalized linear models revealed that descriptors of both present landscape structure and past grassland history are significant determinants of genetic variation in the Briza demes. Genetic structure and levels of within-deme diversity are influenced by the size of grassland fragments, the type of habitat surrounding the grasslands, the size/spatial extent of the demes, the geographic position of the demes and the historical continuity of the grassland fragments. 3 Gene diversity (H) was higher in demes from grassland polygons with a high proportion of adjacent grassland, higher in the more extensive demes, and decreased northwards within the study area. 4 The negative association between the inbreeding coefficient (FIS) and grassland continuity is interpreted in terms of a two-stage colonization process: recruitment into young grasslands leads initially to spatial patchiness, but subsequent selection in maturing pastures occurs within an increasingly uniform and dense sward. 5 Despite a weak overall genetic structure (as indicated by Bayesian cluster analysis) the between-deme FST was significant. Linear discriminant analysis of within-deme allele frequencies grouped the demes according to the age and previous land-use history of their grassland polygons. The convergence of the allele frequency profiles in the younger grasslands towards those of the old grasslands is consistent with convergence of selective regimes as pastures mature towards an increasingly uniform, dense sward and characteristic species assemblage. 6 The genetic composition of demes of a grassland species appears to be influenced by the process of plant community convergence during grassland development – complementing the recent finding that convergence of species composition in experimental assemblages of grassland plants is dependent on the genotypic composition of the component species

  • 34. Reitalu, Triin
    et al.
    Prentice, Honor C.
    Sykes, Martin T.
    Lönn, Mikael
    Södertörn University, School of Life Sciences.
    Jönsson, Lotten
    Hall, Karin
    Plant species segregation on different spatial scales in semi-natural grasslands2008In: Journal of Vegetation Science, ISSN 1100-9233, E-ISSN 1654-1103, Vol. 19, no 3, p. 407-416Article in journal (Refereed)
    Abstract [en]

    Question: We studied the patterns of plant species co-occurrence on three, nested, spatial scales in semi-natural grassland communities and explored the possible ecological processes underlying the patterns. Location: Dry, semi-natural grasslands in a 4.5 km x 4.5 km area on the Baltic Island of Oland (Sweden). Methods: The study used replicated samples on three, nested, spatial scales: 50 cm x 50 cm plots (N= 516), grassland patches (N = 109) and the whole landscape (N= 6). We used a null model approach to study species co-occurrence patterns and compared the ecological amplitudes of the pairs of species contributing most to the patterns. We used linear models to search for associations between species segregation and environmental and landscape factors. Results and Conclusions: Our results support the prediction that patterns of species co-occurrence are likely to be influenced by different mechanisms on different spatial scales. On the plot scale, we interpreted the species segregation in terms of species interactions. The degree of species segregation was significantly associated with the plots'positions within the grassland patches (edge effects) and with management intensity of the grasslands - both variables can be assumed to influence species interactions. On the grassland patch scale, we interpreted the species segregation in terms of within-patch environmental heterogeneity. The degree of segregation was significantly associated with the area of the grassland patches and with management intensity - both variables that are likely to be related to environmental heterogeneity within the grasslands. Species segregation on the landscape scale was interpreted in terms of environmental heterogeneity among grassland patches and was significantly associated with land-use history

  • 35. Reitalu, Triin
    et al.
    Sykes, Martin T.
    Johansson, Lotten M.
    Lönn, Mikael
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Environmental science.
    Hall, Karin
    Vanderwalle, Marie
    Prentice, Honor C.
    Small-scale plant species richness and evenness in semi-natural grasslands respond differently to habitat fragmentation2009In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 142, no 4, p. 899-908Article in journal (Refereed)
    Abstract [en]

    The study explores whether small-scale species diversity, species evenness and species richness in semi-natural grassland communities are similarly associated with present management regime and/or present and historical landscape context (percentage of different land-cover types in the surroundings). Species diversity, evenness and richness were recorded within 441 50 × 50 cm grassland plots in 4.5 × 4.5 km agricultural landscape on Öland, Sweden. Recent and historical land-cover maps (years 2004, 1959, 1938, 1835, and 1800) were used to characterize the present and past landscape context of the sampled vegetation plots. Partial regression and simultaneous autoregressive models were used to explore the relationships between species diversity measures (Shannon diversity, richness and evenness) and different explanatory variables while accounting for spatial autocorrelation in the data. The results indicated that species richness was relatively sensitive to grassland isolation, while the response of species evenness to isolation was characterized by a degree of inertia. Because the richness and evenness components of species diversity may respond differently to habitat fragmentation, we suggest that monitoring projects and empirical studies that focus on changes in biodiversity in semi-natural grasslands should include the assessment of species evenness – as a complement to the assessment of species richness. In addition, our results indicated that the development and persistence of a species-rich and even grassland vegetation was favoured in areas that have historically (in the 19th century) been surrounded by grasslands. Information on landscape history should, whenever possible, be incorporated into the planning of strategies for grassland conservation.

  • 36. Wallin, Lotta
    et al.
    Svensson, Brita M.
    Lönn, Mikael
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Environmental science.
    Artificial dispersal as a restoration tool in meadows: Sowing or planting?2009In: Restoration Ecology, ISSN 1061-2971, E-ISSN 1526-100X, Vol. 17, no 2, p. 270-279Article in journal (Refereed)
    Abstract [en]

    Habitat fragmentation and the abandonment of former agricultural practices have led to extremely low dispersal rates for plant species growing in traditionally managed hay meadows in Sweden. Historically, seed dispersal between populations was maintained by hay movement, grazing animals, and farmers sharing their equipment. Because these means of dispersal typically are no longer occurring, artificial dispersal using seeds and plug-plants is tested here as a restoration tool. In this study, we chose two perennial herbs commonly occurring in meadows as test species, viz, Hypochoeris maculata L. (Asteraceae) and Succisa pratensis Moench. (Dipsacaceae). We found that plug-plant transplants were twice as effective as seed sowing for both species. The seed collection site was found to be important for seed-based establishment and survival; consequently, the choice of donor meadow is important when acquiring seeds used for restoration. We also found that survival of plants introduced as seeds was generally lower at sites harboring species favored by nitrogen as well as at sites in later successional phases. Both methods of introducing meadow species worked well, even though long-term establishment may well be more successful with the plug-plant method due to higher plug-plant establishment 2 years after introduction in the field.

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