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1.	Brunhoff, Cecilia, et al. (author) Glacial survival or late glacial colonization? Phylogeography of the root vole (Microtus oeconomus) in north-west Norway 2006 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 33:12, s. 2136-2144 Journal article (peer-reviewed)abstract Aim It has been proposed that the root vole subspecies, Microtus oeconomus finmarchicus, survived the last glacial period on islands on the north-west coast of Norway. The Norwegian island of Andoya may have constituted the only site with permanent ice-free conditions. Geological surveys and fossil finds from Andoya demonstrate that survival throughout the last glacial maximum was probably possible for some plants and animals. In this study we aim to infer the recent evolutionary history of Norwegian root vole populations and to evaluate the glacial survival hypothesis. Methods DNA sequence variation in the mitochondrial cytochrome b gene was studied in 46 root voles from 19 localities. Location Northern Fennoscandia and north-west Russia with a focus on islands on the north-west coast of Norway. Results The phylogeographical analyses revealed two North European phylogroups labelled 'Andoya' and 'Fennoscandia'. The Andoya phylogroup contained root voles from the Norwegian islands of Andoya, Ringvassoya and Reinoya and two localities in north-west Russia. The Fennoscandian phylogroup encompassed root voles from the three Norwegian islands of Kvaloya, Hakoya and Arnoya and the remaining specimens from Norway, northern Sweden and Finland. Nucleotide diversity within the Andoya and Fennoscandian phylogroups was similar, ranging from 0.5% to 0.7%. Main conclusions Both our genetic data and previously published morphological data are consistent with in situ glacial survival of root voles on Andoya during the last glacial maximum. However, the level of genetic diversity observed in the extant island populations, the past periods of severe climatic conditions on Andoya and the ecology of the root vole are somewhat difficult to reconcile with this model. A biogeographical scenario involving late glacial recolonization along the northern coasts of Russia and Norway therefore represents a viable alternative. Our results demonstrate that complex recolonization and extinction histories can generate intricate phylogeographical patterns and relatively high levels of genetic variation in northern populations.
2.	Bruun, Hans Henrik, et al. (author) Nested communities of alpine plants on isolated mountains: relative importance of colonization and extinction 2003 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 30:2, s. 297-303 Journal article (peer-reviewed)abstract Aim This paper seeks to investigate whether alpine floras on isolated mountains in boreal forest show nestedness, and, if that is the case, to determine whether selective extinction or colonization is the likely cause of the observed patterns. Location Isolated mountains in the boreal coniferous forests of northern Sweden (province of Norrbotten, c. 66°N; 18°E). The timberline in the region probably has been 300-400 m above the present some thousands of years before present, potentially covering these mountains. Methods A data matrix of twenty-seven alpine plant species on twenty-seven isolated mountains was subjected to nested subsets analysis. Extinction probability was assumed to increase with decreasing area, and colonization probability was assumed to decrease with increasing isolation. By sorting the data matrix by these factors and sequentially computing the degree of nestedness, we were able to determine whether the alpine floras were structured mainly by selective extinction or mainly by differential colonization. Results When ordered by decreasing area the data matrix was significantly more nested than random, but that was not the case when ordered by decreasing isolation. Ordering by maximum altitude also produced significant nestedness. Main conclusions Contrary to the conventional view that isolated mountains were completely covered with boreal forest some thousands of years ago, the nestedness patterns of alpine plants indicate that many of them survived the forest period on the isolated mountains, probably on cliffs and slopes too steep for the formation of closed forest.
3.	Connor, Simon E., et al. (author) The ecological impact of oceanic island colonization - a palaeoecological perspective from the Azores 2012 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 39:6, s. 1007-1023 Journal article (peer-reviewed)abstract Aim In many cases, human colonization drastically modified the ecosystems of remote oceanic islands before scientists arrived to document the changes. Palaeoecological records before and after human colonization provide insights into the original ecosystems and an assessment of subsequent human impact. We used pollen analysis to compare the impact of 15th century colonization of the Azores with that of natural disturbances such as volcanic eruptions and climate changes. Location Azores archipelago, Atlantic Ocean. Methods Sediment records from three highland sites in the Azores (on the islands of Pico and Flores) were dated radiometrically and analysed palynologically. Pollen taxa were classified as native, endemic or introduced based on comparison with flora lists. Data were statistically zoned and temporal trends identified using detrended correspondence analysis. Results Human colonization of the Azores resulted in rapid, widespread, persistent vegetation changes on a scale unprecedented in the last 2700 years, detectable through the decline of dominant trees, the spread of grasses and fire-tolerant species, the introduction of exotic plants, evidence for grazing and fire, and changes to soils and moisture availability. During the same period, volcanic eruptions appear to have had more localized impacts on the vegetation, lasting 5001000 years and favouring endemic taxa. The effect of late Holocene climatic changes on the highland vegetation of the Azores seems to have been minor. Palaeoecological data indicate that at least two plant species went extinct on Pico after human colonization and that some plants regarded as introduced were almost certainly part of the original flora of the islands. Despite a consistent signal of human impact, compositional differences between Juniperus brevifolia communities on Pico and Flores remained after colonization. Main conclusions Human colonization had a greater impact on the pristine vegetation of Pico and Flores than climatic changes and volcanic activity during recent millennia. The similarity between post-colonization changes on the Azores and other oceanic islands suggests a consistent pattern and scale to historical-era human impact on otherwise pristine ecosystems. These characteristics could be used to further elaborate biogeographical theory and direct conservation efforts towards species that appear most susceptible to human activity.
4.	de Dinechin, Marc, et al. (author) Speciation chronology of rockhopper penguins inferred from molecular, geological and palaeoceanographic data 2009 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 36:4, s. 693-702 Journal article (peer-reviewed)abstract The Southern Ocean is split into several biogeographical provinces between convergence zones that separate watermasses of different temperatures. Recent molecular phylogenies have uncovered a strong phylogeographic structure among rockhopper penguin populations, Eudyptes chrysocome sensu lato, from different biogeographical provinces. These studies suggested a reclassification as three species in two major clades, corresponding, respectively, to warm, subtropical and cold sub-Antarctic watermasses rather than to geographic proximity. Such a phylogeographic pattern, also observed in plants, invertebrates and fishes of the Southern Ocean, suggests that past changes in the positions of watermasses may have affected the evolutionary history of penguins. We calculated divergence times among various rockhopper penguin clades and calibrated these data with palaeomagmatic and palaeoceanographic events to generate a speciation chronology in rockhopper penguins. Southern Ocean. Divergence times between populations were calculated using five distinct mitochondrial DNA loci, and assuming a molecular clock model as implemented in mdiv. The molecular evolution rate of rockhopper penguins was calibrated using the radiochronological age of St Paul Island and Amsterdam Island in the southern Indian Ocean. Separations within other clades were correlated with palaeoceanographic data using this calibrated rate. The split between the Atlantic and Indian populations of rockhopper penguins was dated as 0.25 Ma, using the date of emergence of St Paul and Amsterdam islands, and the divergence between sub-Antarctic and subtropical rockhopper penguins was dated as c. 0.9 Ma (i.e. during the mid-Pleistocene transition, a major change in the Earth's climate cycles). The mid-Pleistocene transition is known to have caused a major southward shift in watermasses in the Southern Ocean, thus changing the environment around the northernmost rockhopper penguin breeding sites. This ecological isolation of northernmost populations may have caused vicariant speciation, splitting the species into two major clades. After the emergence of St Paul and Amsterdam islands in the subtropical Indian Ocean 0.25 Ma, these islands were colonized by penguins from the subtropical Atlantic, 6000 km away, rather than by penguins from the sub-Antarctic Indian Ocean, 5000 km closer.
5.	Giesecke, Thomas, et al. (author) The effect of past changes in inter-annual temperature variability on tree distribution limits 2010 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 37:7, s. 1394-1405 Journal article (peer-reviewed)abstract Aim The northern limits of temperate broadleaved species in Fennoscanndia are controlled by their requirements for summer warmth for successful regeneration and growth as well as by the detrimental effects of winter cold on plant tissue. However, occurrences of meteorological conditions with detrimental effects on individual species are rare events rather than a reflection of average conditions. We explore the effect of changes in inter-annual temperature variability on the abundances of the tree species Tilia cordata, Quercus robur and Ulmus glabra near their distribution limits using a process-based model of ecosystem dynamics. Location A site in central Sweden and a site in southern Finland were used as examples for the ecotone between boreal and temperate forests in Fennoscandia. The Finnish site was selected because of the availability of varve-thickness data. Methods The dynamic vegetation model LPJ-GUESS was run with four scenarios of inter-annual temperature forcing for the last 10,000 years. In one scenario the variability in the thickness of summer and winter varves from the annually laminated lake in Finland was used as a proxy for past inter-annual temperature variability. Two scenarios were devised to explore systematically the effect of stepwise changes in the variance and shape parameter of a probability distribution. All variability scenarios were run both with and without the long-term trend in Holocene temperature change predicted by an atmospheric general circulation model. Results Directional changes in inter-annual temperature variability have significant effects on simulated tree distribution limits through time. Variations in inter-annual temperature variability alone are shown to alter vegetation composition by magnitudes similar to the magnitude of changes driven by variation in mean temperatures. Main conclusions The varve data indicate that inter-annual climate variability has changed in the past. The model results show that past changes in species abundance can be explained by changes in the inter-annual variability of climate parameters as well as by mean climate. Because inter-annual climatic variability is predicted to change in the future, this component of climate change should be taken into account both when making projections of future plant distributions and when interpreting vegetation history.
6.	Giesecke, Thomas, et al. (author) Towards an understanding of the Holocene distribution of Fagus sylvatica L. 2007 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 34:1, s. 118-131 Journal article (peer-reviewed)abstract Aim Understanding the driving forces and mechanisms of changes in past plant distribution and abundance will help assess the biological consequences of future climate change scenarios. The aim of this paper is to investigate whether modelled patterns of climate parameters 6000 years ago can account for the European distribution of Fagus sylvatica at that time. Consideration is also given to the role of non-climatic parameters as driving forces of the Holocene spread and population expansion of F. sylvatica. Location Europe. Methods European distributions were simulated using a physiologically-based bioclimatic model (STASH) driven by three different atmospheric general circulation model (AGCM) outputs for 6000 years ago. Results The three simulations generally showed F. sylvatica to have potentially been as widespread 6000 years ago as it is today, which gives a profound mismatch with pollen-based reconstructions of the F. sylvatica distribution at that time. The results indicate that drier conditions during the growing season 6000 years ago could have caused a restriction of the range in the south. Poorer growth conditions with consequently reduced competitive ability were modelled for large parts of France. Main conclusions Consideration of the entire European range of F. sylvatica showed that no single driving force could account for the observed distributional limits 6000 years ago, or the pattern of spread during the Holocene. Climatic factors, particularly drought during the growing season, are the likely major determinants of the potential range. Climatic factors are regionally moderated by competition, disturbance effects and the intrinsically slow rate of population increase of F. sylvatica. Dynamic vegetation modelling is needed to account for potentially important competitive interactions and their relationship with changing climate. We identify uncertainties in the climate and pollen data, as well as the bioclimatic model, which suggest that the current study does not identify whether or not climate determined the distribution of F. sylvatica 6000 years ago. Pollen data are better suited for comparison with relative abundance gradients rather than absolute distributional limits. These uncertainties from a study of the past, where we have information about plant distribution and abundance, argue for extreme caution in making forecasts for the future using equilibrium models.
7.	Gritti, Emmanuel, et al. (author) Vulnerability of Mediterranean Basin ecosystems to climate change and invasion by exotic plant species 2006 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 33:1, s. 145-157 Journal article (peer-reviewed)abstract Aim To assess at a broad scale the vulnerability of Mediterranean vegetation to alien plant invasion under different climatic and disturbance scenarios. Location We simulated the vegetation biogeography and dynamics on five of the main islands of the Mediterranean Basin: Mallorca, Corsica, Sardinia, Crete and Lesvos. Methods We used LPJ-GUESS, a generalized ecosystem model based on dynamic processes describing establishment, competition, mortality and ecosystem biogeochemistry. We simulated the vegetation distribution and dynamics using a set of plant functional types (PFTs) based on bioclimatic and physiological parameters, which included tree and shrub PFTs defined especially for the Mediterranean. Additionally, two invasive PFTs, an invasive tree type and an invasive herb type, were defined and used to estimate the vulnerability to invasion of a range of different ecosystems. The model was used to simulate climate changes and associated changes in atmospheric [CO2] to 2050 according to two Special Report on Emissions Scenarios climate scenarios (A1Fi and B1) combined with mean disturbance intervals of 3 and 40 years. Results The simulations and scenarios showed that the effect of climate change alone is likely to be negligible in many of the simulated ecosystems, although not all. The simulated progression of an invasion was highly dependent on the initial ecosystem composition and local environmental conditions, with a particular contrast between drier and wetter parts of the Mediterranean, and between mountain and coastal areas. The rate of ecosystem disturbance was the main factor controlling susceptibility to invasion, strongly influencing vegetation development on the shorter time scale. Main conclusions Further invasion into Mediterranean island ecosystems is likely to be an increasing problem: our simulations predict that, in the longer term, almost all the ecosystems will be dominated by exotic plants irrespective of disturbance rates.
8.	Henningsson, Sara, et al. (author) Does migration promote or restrict circumpolar breeding ranges of arctic birds? 2008 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 35:5, s. 781-790 Journal article (peer-reviewed)abstract Aim: Migration has been suggested to promote large breeding ranges among birds because of the greater mobility of migratory compared to non-migratory species, but migration has also been suggested to restrict breeding ranges because of evolutionary constraints imposed by the genetical migration programme. We aim to investigate the association between migration and the breeding ranges of both land birds and pelagic birds breeding in the Arctic region. Location: The Arctic region. Methods: Information on breeding and wintering range and migratory status of bird species breeding in the Artic tundra biome was compiled from the literature. The association between breeding range, migration distance, primary winter habitat and phylogeny was tested using multivariate general linear models (GLM) and pair-wise Mann-Whitney U tests. Phylogenetic effects were tested for using Mantel’s permutation tests. Results: We found different relationships depending on the species’ major winter habitat. Among birds that are pelagic during winter, long-distance migrants have the largest breeding ranges, while among terrestrial birds, residents and short-distance migrants have the largest breeding ranges. Breeding ranges of coastal birds of all migratory distance classes are comparatively restricted. Main Conclusions: As a new explanation for this pattern we suggest that the possibility to colonize large winter ranges is a key factor for the subsequent expansion of breeding ranges in the Arctic bird communities and possibly also in bird communities of other regions of the world. Because of the reversal in relative extent of continents and oceans between the hemispheres, longitudinally wide winter ranges are more likely for long-distance than short-distance migrants among pelagic birds, while the reverse holds true for birds that use terrestrial winter habitats. For coastal birds both continents and oceans form barriers restricting colonisation of extensive winter quarters and consequently also of extensive breeding ranges regardless of the distance to the winter quarters.
9.	Henningsson, Sara, et al. (author) Patterns and determinants of shorebird species richness in the circumpolar Arctic 2005 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 32:3, s. 383-396 Journal article (peer-reviewed)abstract Aim The intention with this study was first to investigate and describe the broad-scale geographical patterns of species richness of breeding shorebirds (Charadriiformes; families: Charadriidae, Scolopacidae and Haematopodidae) throughout the arctic tundra biome. Secondly, after compensating for the positive relationship between net primary productivity (NPP) and species richness, the relative importance of additional ecological and historical variables for species richness was investigated. The main variables considered are NPP, length of snow- and ice-free season, accessibility of regions depending on migratory flyway systems, tundra area at Pleistocene (120 and 20-18 ka bp) and Holocene (8 ka bp) times, and tundra area at present. Methods Information on shorebird species breeding distributions was compiled from distribution atlases and species accounts. The breeding distributions of shorebirds with ranges partly or completely in the Arctic (a total of 50 species) were mapped in ArcView 3.2 to create a raster grid layer of shorebird species richness at a 1degrees latitude x longitude resolution. The total and mean species richness value was calculated per each 10degrees of longitude sector of the Arctic. The relationships between species richness and the different climatic and environmental variables were analysed on the basis of this sector-wise division of the arctic tundra. The influence of each variable on species richness was investigated using univariate and multivariate analyses (multivariate linear regression and general linear model). Results We found that patterns of breeding shorebird species richness in the Arctic tundra biome are to a large degree determined by the NPP, the length of the snow- or ice-free season, the diversity of migratory flyways, as well as the historical extent of tundra habitat area during the maximum cooling of the last glacial period. Essentially, two main regions are distinguishable in the circumpolar Arctic regarding shorebird community richness. These are a species-rich Beringia-centred region and a species-poor Atlantic-centred region. Main conclusions The underlying explanations to these major trends may primarily be attributed to factors that operate at present through accessibility of areas from contemporary migration flyways, as well as processes that operated in the past during and after the last glacial cycle. The most prominent influence on the shorebird diversity was found for NPP in combination with the diversity of migratory flyways. These flyways provide the links between breeding and wintering resources, often separated by huge distances, and the geographical and ecological conditions associated with the shorebirds' migration seem to be of particular importance for their breeding diversity in different sectors of circumpolar tundra.
10.	Kuchta, Shawn, et al. (author) Closing the ring: historical biogeography of the salamander ring species Ensatina eschscholtzii 2009 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 36:5, s. 982-995 Journal article (peer-reviewed)abstract The salamander Ensatina eschscholtzii Gray is a classic example of a ring species, or a species that has expanded around a central barrier to form a secondary contact characterized by species-level divergence. In the original formulation of the ring species scenario, an explicit biogeographical model was proposed to account for the occurrence of intraspecific sympatry between two subspecies in southern California (the 'southern closure' model). Here we develop an alternative ring species model that is informed by the geomorphological development of the California Coast Ranges, and which situates the point of ring closure in the Monterey Bay region of central coastal California (the 'Monterey closure' model). Our study has two aims. The first is to use phylogenetic methods to evaluate the two competing biogeographical models. The second is to describe patterns of phylogeographical diversity throughout the range of the Ensatina complex, and to compare these patterns with previously published molecular systematic data. Western North America, with a focus on the state of California, USA. We obtained mitochondrial DNA sequence data from 385 individuals from 224 populations. A phylogeny was inferred using Bayesian techniques, and the geographical distributions of haplotypes and clades were mapped. The two biogeographical ring species models were tested against our Bayesian topology, including the associated Bayesian 95% credible set of trees. High levels of phylogeographical diversity were revealed, especially in central coastal and northern California. Our Bayesian topology contradicts the Monterey closure model; however, 0.08% of the trees in our Bayesian 95% credible set are consistent with this model. In contrast, the classic ring species biogeographical model (the southern closure model) is consistent with our Bayesian topology, as were 99.92% of the trees in our 95% credible set. Our Bayesian phylogenetic analysis most strongly supports the classic ring species model, modified to accommodate an improved understanding of the complex geomorphological evolution of the California Coast Ranges. In addition, high levels of phylogeographical diversity in central and northern California were identified, which is consistent with the striking levels of allozymic differentiation reported previously from those regions.
11.	Rundgren, Mats, et al. (author) Plant survival in Iceland during periods of glaciation? 1999 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 26:2, s. 387-396 Journal article (peer-reviewed)abstract Aim: The paper addresses the classical question of possible plant survival in Iceland during the last glacial period in the light of a palaeobotanical record from northern Iceland, spanning the period 11,300-9000 BP, including the Younger Dryas stadial. We review the Late Cenozoic fossil plant record, the past debate on glacial plant refugia in Iceland, and the evidence for ice-free areas during the Weichselian. Location: The investigated lake sediment record comes from Lake Torfadalsvatn, which is situated in the northwestern part of the Skagi peninsula in northern Iceland. Methods: The sediment chronology was constructed from the occurrence of the Vedde Ash and the Saksunarvatn ash, two well-dated Icelandic tephras, together with the results from five AMS and conventional radiocarbon dates performed on bulk sediment samples. The vegetational reconstruction was based on detailed pollen analysis of the sediment sequence. Results: The pollen analysis revealed that many of the taxa present in the area prior to the Younger Dryas stadial continued to produce pollen during that cold event. The more or less immediate reappearance of a few other pollen taxa at the Younger Dryas-Preboreal boundary suggests that these plants also survived, even if they did not produce sufficient pollen to be recorded during the Younger Dryas stadial. Main conclusions: We conclude that the relatively high plant diversity found in high Arctic areas and present-day nunataks in Iceland and Greenland, together with the fact that many plant species were able to survive the Younger Dryas stadial on the Skagi peninsula, suggest that species with high tolerance for climate fluctuations also survived the whole Weichselian in Iceland. This conclusion is supported by recent palaeoclimatic data from ice-cores and deep-sea sediments, indicating that Icelandic climate during the last glacial was only occasionally slightly colder than during the Younger Dryas stadial.
12.	Struwe, Lena, et al. (author) Spatial evolutionary and ecological vicariance analysis (SEEVA), a novel approach to biogeography and speciation research, with an example from Brazilian Gentianaceae 2011 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 38:10, s. 1841-1854 Journal article (peer-reviewed)abstract Aim Spatial evolutionary and ecological vicariance analysis (SEEVA) is a simple analytical method that evaluates environmental or ecological divergence associated with evolutionary splits. It integrates evolutionary hypotheses, phylogenetic data, and spatial, temporal, environmental and geographical information to elucidate patterns. Using a phylogeny of Prepusa Mart. and Senaea Taub. (Angiospermae: Gentianaceae), SEEVA is used to describe the radiation and ecological patterns of this basal gentian group across south-eastern Brazil. Location Latin America, global. Methods Environmental data for 151 geolocated botanical collections, associated with specimens from seven species, were compiled with ARCGIS, and were matched with geolocated base layers of eight climatological variables, as well as one each of geological, soil type, elevational and vegetation variables. Sister groups were defined on the basis of the six nested nodes that defined the phylogenetic tree of these two genera. A (0, 1)-scaled divergence index (D) was defined and tested for each of 12 environmental and for each of the six phylogenetic nodes, by means of contingency analyses. We contrast divergence indices of nested clades, allopatric and sympatric sister clades. Results The level of ecological divergence between sister clades/species, defined in terms of D measures, was substantial for five of six nodes, with 21 of 72 environmental comparisons having D > 0.75. Soil types and geological age of bedrock were strongly divergent only for basal nodes in the phylogeny, by contrast with temperature and precipitation, which exhibited strong divergence at all nodes. There has been strong divergence and progressive occupation of wetter and colder habitats throughout the history of Prepusa. Nodes separating allopatric sister clades exhibited larger niche divergence than did those separating sympatric sister clades. Main conclusions SEEVA provides a multi-source, direct analysis method for correlating field collections, phylogenetic hypotheses, species distributions and georeferenced environmental data. Using SEEVA, it was possible to quantify and test the divergence between sister lineages, illustrating both niche conservatism and ecological specialization. SEEVA permits elucidation of historical and ecological vicariance for evolutionary lineages, and is amenable to wide application, taxonomically, geographically and ecologically.
13.	Tyler, Torbjörn (author) Detecting migration routes and barriers by examining the distribution of species in an apomictic species complex 2000 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 27:4, s. 979-988 Journal article (peer-reviewed)abstract Aim The distribution of taxa ('microspecies') in the apomictic species complexes Hieracium L. sect. Hieracium and H. sect. Vulgata (Griseb.) Willk. and Lange have been analysed to test whether the geographical distribution of species within each complex will reflect historical processes and phenomena, e.g. historical barriers to migration and range expansion. It is argued that apomictic species can be used for phylogeographic analysis in the same way as organelle haplotypes or multilocus genotypes. Location The investigated area is the Nordic countries excluding Iceland, together with the Baltic islands of Saarema (Estonia) and Rugen (Germany). Methods The presence or absence of 160 species of H. sect. Hieracium and 165 species of H. sect. Vulgata was recorded in 39 geographical areas. Based on this dataset, Jaccard similarity indices were calculated and subjected to UPGMA cluster analysis and non-metric multidimensional scaling (MDS). Results For both species complexes, the larger water surfaces were found to represent discontinuities in species composition, interpreted as migration barriers. Some inland migration barriers were also indicated, e.g. in northern-central Sweden. The Scandes seems to have constituted a migration barrier for H. sect. Vulgata. Some areas in southwestern Sweden represent discontinuities in the distribution of species within H. sect. Hieracium. Main conclusions The revealed geographical patterns in species composition, as well as the differences in the patterns for the two species complexes, are readily explainable as reflecting historical migration routes and barriers. Further analysis using apomictic taxa as 'markers' may give important phylogeographic insights. The pros and cons of using microspecies, as opposed to molecular markers, in historical biogeography is discussed.
14.	Tyler, Torbjörn (author) Geographical distribution of allozyme variation in relation to post-glacial history in Carex digitata, a widespread European woodland sedge 2002 In: Journal of Biogeography. - : Wiley. - 1365-2699 .- 0305-0270. ; 29:7, s. 919-930 Journal article (peer-reviewed)abstract Aim To investigate the distribution, and broad-scale geographical patterns, of variation, in the widespread boreo-nemoral woodland herb Carex digitata throughout its native European range. To interpret the revealed geographical pattern of variation in terms of glacial survival, post-glacial migration and inter-regional gene-flow. Location The whole of Europe divided into twenty-five geographical regions. Methods Genetic variation at nine polymorphic allozyme loci was analysed in 10-25 individuals from 66 populations from throughout the European range of C. digitata . Allele frequencies were calculated both at the level of populations and at the level of geographical regions, and these frequencies were used to calculate the Cavalli-Sforza chord distance (CSCD). CSCD between neighbouring regions were presented on geographical maps. CSCD at both the population and the regional level were subjected to UPGMA cluster analysis. Standard measures of genetic diversity were calculated and divided into within population, region and species components. Results Most alleles had a scattered distribution throughout, but several alleles were mainly found in Fennoscandia and regional allelic richness was the highest here. Cluster analysis on the level of populations did not recover any geographical structure. However, genetic distances between regions, each consisting of 1-4 populations, revealed a clear geographical pattern. Genetic distances were low between (1) Scandinavian and British regions and (2) between Mediterranean regions, moderate between Central European regions and high between far-east European and Caucasian regions. Main conclusions A post-glacial scenario involving independent glacial survivals in south-eastern European Russia, the Caucasian Mountains, the Mediterranean area and central Europe is proposed. Northern Europe (i.e. Fennoscandia) appears to have been colonized through many independent long-distance dispersals from different extra-Fennoscandian populations. High regional population densities in Fennoscandia are assumed to have facilitated accumulation of genetic variation and inter-regional gene-flow as compared with more southern populations which are generally of restricted size and appear to have been mutually isolated and subjected to strong genetic drift.
15.	Perrigo, Allison L., et al. (author) What's on your boots : an investigation into the role we play in protist dispersal 2012 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 39:5, s. 998-1003 Journal article (peer-reviewed)abstract D. M. Wilkinson (2010, Journal of Biogeography, 37, 393–397) suggested that anthropogenic dispersal is an understudied and potentially important factor in terrestrial protist biogeography. We investigated human footwear as a potential vector of dictyostelids, a diverse group of amoebae that includes both geographically restricted and cosmopolitan species. Eighteen pairs of boots were examined and dictyostelids were isolated from nearly all samples larger than 5.0 g. In total, six dictyostelid isolates were recovered, corresponding to four species –Dictyostelium minutum, D. sphaerocephalum, D. leptosomopsis and a new species, Polysphondylium sp. 1. Myxogastrid amoebae and acrasid-like aggregations were also observed. Thus anthropogenic dispersal of naked amoebae appears to occur. The possible role of variations in dictyostelid fruiting body morphologies in dispersal potential is also discussed. These results support Wilkinson’s proposal and suggest that dictyostelids may be a useful group with which to study anthropogenic dispersal of terrestrial protists.
16.	Elmberg, Johan, 1960-, et al. (author) Abundance-distribution relationships on interacting trophic levels : the case of lake-nesting waterfowl and dytiscid water beetles 2000 In: Journal of Biogeography. - 0305-0270 .- 1365-2699. - 0305-0270 ; 27:4, s. 821-827 Journal article (peer-reviewed)abstract Aim To compare patterns in local abundance, regional distribution and body size in waterfowl and dytiscid beetles sampled from the same lakes. Location Thirty Swedish lakes, 56-63 degrees N. Methods Birds were censused repeatedly, at which time submerged activity traps were placed on the littoral to catch invertebrates. Avian patterns were analysed separately for four different selections of species, each motivated on functional or phylogenetical grounds. Patterns in dytiscid beetles have been described earlier in Nilsson, Elmberg & Sjoberg (1994). Results Although there were large differences between individual lakes, there was no significant latitudinal gradient at the lake level in either species richness or abundance in any of the bird groupings. Lakes which were rich in species and numbers of dytiscid beetles were also rich in species and numbers of all four waterfowl groups. Three of the four bird groups conform with the general pattern of widely distributed species being more abundant locally, as do dytiscid beetles in the same lakes. Body mass and local abundance were correlated in one of the four birds groups only, i.e. dabbling ducks, (Anas spp.). Main conclusions We find evidence for a similar and positive local abundance-distribution relationship in dytiscid beetles and waterfowl breeding in the same lakes, but no common general pattern in local abundance vs. body size.
17.	Aggemyr, Elsa, et al. (author) Landscape structure and land use history influence changes in island plant composition after 100 years 2012 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 39:9, s. 1645-1656 Journal article (peer-reviewed)abstract Aim We investigated how current and historical land use and landscape structure affect species richness and the processes of extinction, immigration and species turnover. Location The northern part of the Stockholm archipelago, Baltic Sea, Sweden. We resurveyed 27 islands ranging from 0.3 to 33 ha in area. Methods We compared current plant survey data, cadastral maps and aerial photographs with records obtained from a survey in 1908, using databases and a digital elevation model to examine changes in plant community dynamics in space and time. We examined the effects of local and landscape structure and land use changes on plant species dynamics by using stepwise regression in relation to eight local and three landscape variables. The eight local variables were area, relative age, shape, soil heterogeneity, bedrock ratio, number of houses, forest cover change, and grazing 100 years ago. The three landscape variables were distance to mainland, distance to closest island with a farm 100 years ago, and structural connectivity. Hanskis connectivity measure was modified to incorporate both connectivity and fragmentation. Results The investigated islands have undergone drastic changes, with increasing forest cover, habitation, and abandonment of grassland management. Although the total species richness increased by 31% and mean island area by 23%, we found no significant increase in species richness per unit area. Local variables explain past species richness (100 years ago), whereas both local and landscape variables explain current species richness, extinctions, immigrations and species turnover. Grazing that occurred 100 years ago still influences species richness, even though grazing management was abandoned several decades ago. The evidence clearly shows an increase in nitrophilous plant species, particularly among immigrant species. Main conclusions This study highlights the importance of including land use history when interpreting current patterns of species richness. Furthermore, local environment and landscape patterns affect important ecological processes such as immigration, extinction and species turnover, and hence should be included when assessing the impact of habitat fragmentation and land use change. We suggest that our modified structural connectivity measure can be applied to other types of landscapes to investigate the effects of fragmentation and habitat loss.
18.	Andersson, Elisabeth, et al. (author) Plant dispersal in boreal rivers and its relation to the diversity of riparian flora 2000 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 27:5, s. 1095-1106 Journal article (peer-reviewed)abstract Aim The paper has four major objectives: (1) to determine whether diaspore mimics accurately represent dispersal dynamics of real diaspores in a free-flowing river; (2) to estimate distance travelled and reasons for stranding of floating diaspores along a free-flowing river; (3) to test if species composition and seedling recruitment vary with the ability of the riverbank to trap waterborne drift; and (4) to compare diaspore dispersal in a free-flowing river with that in a regulated river where current velocity has been reduced. Location The field work was conducted in two 7th-order boreal rivers in northern Sweden, the free-flowing Vindel River and the regulated Ume River. Methods We performed a series of dispersal experiments. We tested the usefulness wooden cubes of diaspore mimics for performing dispersal experiments by releasing cubes and achenes of Helianthus annuus and compare their dispersal patterns in the free-flowing Vindel River. We used the cubes to identify 50-m long sections along the river with different trapping capacity, i.e. the number of stranded diaspore mimics within a 50-m section. We then related the number of stranded diaspore mimics to the vascular plant flora, the proportions of species with long or short floating times (i.e. more than or less than 2 days, respectively), the number of seedlings, and to environmental variables within the sections. We also released wooden cubes in a run-of-river impoundment to determine the dispersal capacity of diaspores in a regulated river. Results The cubes were useful as diaspore mimics. They dispersed similarly to achenes of H. annuus. The stranding pattern of diaspore mimics was significantly associated with water current. Species richness of vascular plants per 50-m section increased with the number of stranded mimics. Seedling recruitment, and the proportions of species with short-floating and long-floating diaspores, did not vary with the number of stranded mimics. The ability of a river to transport diaspores downstream was strongly reduced by impoundment. Main conclusions We conclude that patterns of species richness of riparian vegetation is in part determined by the ability of the riverbank to trap waterborne diaspores, but differences in floating ability among species did not affect the species composition along free-flowing rivers.
19.	Appelhans, Marc S., et al. (author) Age and historical biogeography of the pantropically distributed Spathelioideae (Rutaceae, Sapindales) 2012 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 39:7, s. 1235-1250 Journal article (peer-reviewed)abstract Aim The family Rutaceae (rue family) is the largest within the eudicot order Sapindales and is distributed mainly in the tropical and subtropical regions of both the New World and the Old World, with a few genera in temperate zones. The main objective of this study is to present molecular dating and biogeographical analyses of the subfamily Spathelioideae, the earliest branching clade (which includes eight extant genera), to interpret the temporal and spatial origins of this group, ascertaining possible vicariant patterns and dispersal routes and inferring diversification rates through time. Location Pantropics. Methods A dataset comprising a complete taxon sampling at generic level (83.3% at species level) of Spathelioideae was used for a Bayesian molecular dating analysis (beast). Four fossil calibration points and an age constraint for Sapindales were applied. An ancestral area reconstruction analysis utilizing the dispersalextinctioncladogenesis model and diversification rate analyses was conducted. Results Dating analyses indicate that Rutaceae and Spathelioideae are probably of Late Cretaceous origin, after which Spathelioideae split into a Neotropical and a Palaeotropical lineage. The Palaeotropical taxa have their origin inferred in Africa, with postulated dispersal events to the Mediterranean, the Canary Islands, Madagascar and Southeast Asia. The lineages within Spathelioideae evolved at a relatively constant diversification rate. However, abrupt changes in diversification rates are inferred from the beginning of the Miocene and during the Pliocene/Pleistocene. Main conclusions The geographical origin of Spathelioideae probably lies in Africa. The existence of a Neotropical lineage may be the result of a dispersal event at a time in the Late Cretaceous when South America and Africa were still quite close to each other (assuming that our age estimates are close to the actual ages), or by Gondwanan vicariance (assuming that our age estimates provide minimal ages only). Separation of land masses caused by sea level changes during the Pliocene and Pleistocene may have been triggers for speciation in the Caribbean genus Spathelia.
20.	Blake, S., et al. (author) Seed dispersal by Galápagos tortoises 2012 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 39:11, s. 1961-1972 Journal article (peer-reviewed)abstract Aim Large-bodied vertebrates often have a dramatic role in ecosystem function through herbivory, trampling, seed dispersal and nutrient cycling. The iconic Galápagos tortoises (Chelonoidis nigra) are the largest extant terrestrial ectotherms, yet their ecology is poorly known. Large body size should confer a generalist diet, benign digestive processes and long-distance ranging ability, rendering giant tortoises adept seed dispersers. We sought to determine the extent of seed dispersal by Galápagos tortoises and their impact on seed germination for selected species, and to assess potential impacts of tortoise dispersal on the vegetation dynamics of the Galápagos. Location Galápagos, Ecuador. Methods To determine the number of seeds dispersed we identified and counted intact seeds from 120 fresh dung piles in both agricultural and national park land. To estimate the distance over which tortoises move seeds we used estimated digesta retention times from captive tortoises as a proxy for retention times of wild tortoises and tortoise movement data obtained from GPS telemetry. We conducted germination trials for five plant species to determine whether tortoise processing influenced germination success. Results In our dung sample, we found intact seeds from >45 plant species, of which 11 were from introduced species. Tortoises defecated, on average, 464 (SE 95) seeds and 2.8 (SE 0.2) species per dung pile. Seed numbers were dominated by introduced species, particularly in agricultural land. Tortoises frequently moved seeds over long distances; during mean digesta retention times (12days) tortoises moved an average of 394m (SE 34) and a maximum of 4355m over the longest recorded retention time (28days). We did not find evidence that tortoise ingestion or the presence of dung influenced seed germination success. Main conclusions Galápagos tortoises are prodigious seed dispersers, regularly moving large quantities of seeds over long distances. This may confer important advantages to tortoise-dispersed species, including transport of seeds away from the parent plants into sites favourable for germination. More extensive research is needed to quantify germination success, recruitment to adulthood and demography of plants under natural conditions, with and without tortoise dispersal, to determine the seed dispersal effectiveness of Galápagos tortoises.
21.	Bommarco, Riccardo (author) Alien plants associate with widespread generalist arbuscular mycorrhizal fungal taxa: evidence from a continental-scale study using massively parallel 454 sequencing 2011 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 38, s. 1305-1317 Journal article (peer-reviewed)abstract Main conclusions AM fungal communities in the native, invasive and experimentally introduced ranges varied in taxonomic composition and richness, but they shared a pool of geographically widespread, non-host-specific taxa that might support the invasion of a generalist alien plant. Our dataset provides the first geographical overview of AM taxon distributions obtained using a single host-plant species.
22.	Buerki, Sven, et al. (author) An evaluation of new parsimony-based versus parametric inference methods in biogeography : a case study using the globally distributed plant family Sapindaceae 2011 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 38:3, s. 531-550 Journal article (peer-reviewed)abstract Aim Recently developed parametric methods in historical biogeography allow researchers to integrate temporal and palaeogeographical information into the reconstruction of biogeographical scenarios, thus overcoming a known bias of parsimony-based approaches. Here, we compare a parametric method, dispersal-extinction-cladogenesis (DEC), against a parsimony-based method, dispersal-vicariance analysis (DIVA), which does not incorporate branch lengths but accounts for phylogenetic uncertainty through a Bayesian empirical approach (Bayes-DIVA). We analyse the benefits and limitations of each method using the cosmopolitan plant family Sapindaceae as a case study. Location World-wide. Methods Phylogenetic relationships were estimated by Bayesian inference on a large dataset representing generic diversity within Sapindaceae. Lineage divergence times were estimated by penalized likelihood over a sample of trees from the posterior distribution of the phylogeny to account for dating uncertainty in biogeographical reconstructions. We compared biogeographical scenarios between Bayes-DIVA and two different DEC models: one with no geological constraints and another that employed a stratified palaeogeographical model in which dispersal rates were scaled according to area connectivity across four time slices, reflecting the changing continental configuration over the last 110 million years. Results Despite differences in the underlying biogeographical model, Bayes-DIVA and DEC inferred similar biogeographical scenarios. The main differences were: (1) in the timing of dispersal events - which in Bayes-DIVA sometimes conflicts with palaeogeographical information, and (2) in the lower frequency of terminal dispersal events inferred by DEC. Uncertainty in divergence time estimations influenced both the inference of ancestral ranges and the decisiveness with which an area can be assigned to a node. Main conclusions By considering lineage divergence times, the DEC method gives more accurate reconstructions that are in agreement with palaeogeographical evidence. In contrast, Bayes-DIVA showed the highest decisiveness in unequivocally reconstructing ancestral ranges, probably reflecting its ability to integrate phylogenetic uncertainty. Care should be taken in defining the palaeogeographical model in DEC because of the possibility of overestimating the frequency of extinction events, or of inferring ancestral ranges that are outside the extant species ranges, owing to dispersal constraints enforced by the model. The wide-spanning spatial and temporal model proposed here could prove useful for testing large-scale biogeographical patterns in plants.
23.	Campbell, Colin (author) The influence of vegetation type, soil properties and precipitation on the composition of soil mite and microbial communities at the landscape scale 2010 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 37, s. 1317-1328 Journal article (peer-reviewed)abstract The influence of vegetation type and soil properties differed between groups of soil organisms, albeit in a predictable manner, across the 12 sites. Organisms directly associated with plants (fungi), and organisms with microhabitat and resource preferences (Oribatida) were strongly responsive to changes in habitat type. The response of organisms not directly associated with plants (bacteria, archaea) depended on differences in soil properties, while organisms with less clear microhabitat and resource preferences (Mesostigmata) were not strongly responsive to either vegetation type or soil properties. These results show that it is possible to predict the impact of habitat change on specific soil organisms depending on their ecology. Moreover, the community composition of all groups was related to variation in precipitation within the study area, which shows that external factors, such as those caused by climate change, can have a direct effect on belowground communities.
24.	Eidesen, P. B., et al. (author) Repeatedly out of Beringia: Cassiope tetragona embraces the arctic 2007 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 34:9, s. 1559-1574 Journal article (peer-reviewed)abstract Aim Eric Hulten hypothesized that most arctic plants initially radiated from Beringia in the Late Tertiary and persisted in this unglaciated area during the Pleistocene glaciations, while their distribution ranges were repeatedly fragmented and reformed elsewhere. Whereas taxonomic and fossil evidence suggest that Cassiope tetragona originated in Beringia and expanded into the circumarctic area before the onset of the glaciations, lack of chloroplast DNA (cpDNA) variation may suggest that colonization was more recent. We address these contradictory scenarios using high-resolution nuclear markers. Location Circumpolar Arctic. Methods The main analysis was by amplified fragment-length polymorphism (AFLP), while sequences of chloroplast DNA verified the use of Cassiope mertensiana as an outgroup for C. tetragona. Data were analysed using Bayesian clustering, principal coordinates analyses, parsimony and neighbour-joining, and measures of diversity and differentiation were calculated. Results The circumpolar C. tetragona ssp. tetragona was well separated from the North American C. tetragona ssp. saximontana. The genetic structure in ssp. tetragona showed a strong east-west trend, with the Beringian populations in an intermediate position. The highest level of diversity was in Beringia, while the strongest differentiation in the data set was found between the populations from the Siberian Arctic west of Beringia and the remainder. Main conclusions The results are consistent with a Beringian origin of the species, but the levels and geographical patterns of differentiation and gene diversity suggest that the latest expansion from Beringia into the circumarctic was recent, possibly during the current interglacial. The results are in accordance with a recent leading-edge mode of colonization, particularly towards the east throughout Canada/Greenland and across the North Atlantic into Scandinavia and Svalbard. As fossils demonstrate the presence of the species in North Greenland 2.5-2.0 Ma, as well as in the previous interglacial, we conclude that C. tetragona expanded eastwards from Beringia several times and that the earlier emigrants of this woody species became extinct. The last major westward expansion from Beringia seems older, and the data suggest a separate Siberian refugium during at least one glaciation.
25.	Espeland, Marianne, 1981-, et al. (author) The effect of environmental diversification on species diversification in New Caledonian caddisflies (Insecta: Trichoptera: Hydropsychidae) 2010 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 37:5, s. 879-890 Journal article (peer-reviewed)abstract Aim To test whether environmental diversification played a role in the diversification of the New Caledonian Hydropsychinae caddisflies. Location New Caledonia, south-west Pacific. Methods The phylogeny of the New Caledonian Hydropsychinae caddisflies was hypothesized using parsimony and Bayesian methods on molecular characters. The Bayesian analysis was the basis for a comparative analysis of the correlation between phylogeny and three environmental factors: geological substrate (ultrabasic, non-ultrabasic), elevation and precipitation. Phylogenetic divergence times were estimated using a relaxed clock method, and environmental factors were mapped onto a lineage-through-time plot to investigate the timing of environmental diversification in relation to species radiation. The correlation between rainfall and elevation was tested using independent contrasts, and the gamma statistic was calculated to infer the diversification pattern of the group. Results The diversification of extant Orthopsyche–Caledopsyche species began in the Middle–Late Oligocene, when much of the island of New Caledonia was covered by ultrabasic substrate and mountain forming was prevalent. Most lineages originated in the Middle–Late Miocene, a period associated with long-term climate oscillation. Optimization of environmental factors on the phylogeny demonstrated that the New Caledonian Hydropsychinae group adapted to ultrabasic substrate early in its evolutionary history. The clade living mostly on ultrabasic substrate was far more species-rich than the clade living mostly on non-ultrabasic substrate. Elevation and rainfall were significantly correlated with each other. The lineage-through-time plot revealed that the main environmental diversification preceded species diversification. A constant speciation through time was rejected, and the negative gamma indicates that most of the diversification occurred early in the history of the clade. According to the inferred phylogeny, the genus Orthopsyche McFarlane is a synonym under Caledopsyche Kimmins, and Abacaria caledona Oláh & Barnard should also be included in Caledopsyche. Main conclusions The age of the radiation does not support a vicariance origin of New Caledonian Hydropsychinae caddisflies. Environmental diversification pre-dates lineage diversification, and thus environmental heterogeneity potentially played a role in the diversification of the group, by providing a variety of fragmented habitats to disperse into, promoting speciation. The negative gamma indicates that the speciation rate slowed as niches started to fill.
26.	Fontana, Sonia L. (author) Coastal dune vegetation and pollen representation in south Buenos Aires Province, Argentina 2005 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 32:4, s. 719-735 Journal article (peer-reviewed)
27.	Hailer, Frank, et al. (author) Phylogeography of the white-tailed eagle, a generalist with large dispersal capacity 2007 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 34:7, s. 1193-1206 Journal article (peer-reviewed)abstract Aim Late Pleistocene glacial changes had a major impact on many boreal and temperate taxa, and this impact can still be detected in the present-day phylogeographic structure of these taxa. However, only minor effects are expected in species with generalist habitat requirements and high dispersal capability. One such species is the white-tailed eagle, Haliaeetus albicilla, and we therefore tested for the expected weak population structure at a continental level in this species. This also allowed us to describe phylogeographic patterns, and to deduce Ice Age refugia and patterns of postglacial recolonization of Eurasia. Location Breeding populations from the easternmost Nearctic (Greenland) and across the Palaearctic (Iceland, continental Europe, central and eastern Asia, and Japan). Methods Sequencing of a 500 base-pair fragment of the mitochondrial DNA control region in 237 samples from throughout the distribution range. Results Our analysis revealed pronounced phylogeographic structure. Overall, low genetic variability was observed across the entire range. Haplotypes clustered in two distinct haplogroups with a predominantly eastern or western distribution, and extensive overlap in Europe. These two major lineages diverged during the late Pleistocene. The eastern haplogroup showed a pattern of rapid population expansion and colonization of Eurasia around the end of the Pleistocene. The western haplogroup had lower diversity and was absent from the populations in eastern Asia. These results suggest survival during the last glaciation in two refugia, probably located in central and western Eurasia, followed by postglacial population expansion and admixture. Relatively high genetic diversity was observed in northern regions that were ice-covered during the last glacial maximum. This, and phylogenetic relationships between haplotypes encountered in the north, indicates substantial population expansion at high latitudes. Areas of glacial meltwater runoff and proglacial lakes could have provided suitable habitats for such population growth. Main conclusions This study shows that glacial climate fluctuations had a substantial impact on white-tailed eagles, both in terms of distribution and demography. These results suggest that even species with large dispersal capabilities and relatively broad habitat requirements were strongly affected by the Pleistocene climatic shifts.
28.	Hedblom, Marcus, et al. (author) Landscape effects on birds in urban woodlands: an analysis of 34 Swedish cities 2010 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 37, s. 1302-1316 Journal article (peer-reviewed)abstract AimTo compare bird abundances in woodlands along gradients from the city centre to the peri-urban area. To evaluate the importance of the proportion of woodland within the city and in the peri-urban landscape to forest bird communities breeding in urban woodlands. To test whether fragmentation effects on birds were linked to the type of peri-urban matrix.LocationA total of 34 Swedish cities with > 10,000 inhabitants in south-central Sweden. The study area covered 105,000 km2, in which 84% of the Swedish population of 9.1 million lives.MethodsRepeated point count surveys were conducted in 2004 in a total of 474 woodlands. General linear models were used to test for possible differences in abundance along urban to peri-urban gradients, and to regress bird abundances in local urban woodlands on: (1) total woodland cover in the city, (2) total woodland cover in the peri-urban landscape, (3) the interaction between woodland cover in the city and in the peri-urban area, (4) region, and (5) human density.ResultsMore than 12,000 individuals of 100 forest bird species were recorded. Of the 34 most common species detected, 13 bird species had higher abundances in urban than in peri-urban woodlands, and seven species showed the opposite trend. The bird community of urban woodlands was characterized by species associated with deciduous forests and tree nesters, whereas the bird community of peri-urban woodlands was characterized by species associated with coniferous woodland and ground nesters. Twelve species were significantly linearly associated with the proportion of urban woodland and/or the proportion of peri-urban woodland, and a further eight species were associated with the interaction between these two factors. Local breeding bird abundances of four species were significantly positively associated with the proportion of urban woodland only in farmland-dominated landscapes.Main conclusionsFragmentation effects on some urban birds are linked to the type of peri-urban matrix. In farmland landscapes, peri-urban woodlands may have been too scarce to act as a source of bird immigrants to fragmented urban woodlands. To maintain populations of specialized forest birds within cities in landscapes dominated by agriculture, it is of paramount importance to conserve any remaining urban woodlands.
29.	Johansen, S., et al. (author) A contribution to the discussion of biota dispersal with drift ice and driftwood in the North Atlantic 2001 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 28:1, s. 105-115 Journal article (peer-reviewed)
30.	Jonsson, Micael, et al. (author) Direct and indirect effects of area, energy and habitat heterogeneity on breeding bird communities 2011 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 38:6, s. 1186-1196 Journal article (peer-reviewed)abstract Aim To compare the ability of island biogeography theory, niche theory and species–energy theory to explain patterns of species richness and density for breeding bird communities across islands with contrasting characteristics.Location Thirty forested islands in two freshwater lakes in the boreal forest zone of northern Sweden (65°55′ N to 66°09′ N; 17°43′ E to 17°55′ E).Methods We performed bird censuses on 30 lake islands that have each previously been well characterized in terms of size, isolation, habitat heterogeneity (plant diversity and forest age), net primary productivity (NPP), and invertebrate prey abundance. To test the relative abilities of island biogeography theory, niche theory and species–energy theory to describe bird community patterns, we used both traditional statistical approaches (linear and multiple regressions) and structural equation modelling (SEM; in which both direct and indirect influences can be quantified).Results Using regression-based approaches, area and bird abundance were the two most important predictors of bird species richness. However, when the data were analysed by SEM, area was not found to exert a direct effect on bird species richness. Instead, terrestrial prey abundance was the strongest predictor of bird abundance, and bird abundance in combination with NPP was the best predictor of bird species richness. Area was only of indirect importance through its positive effect on terrestrial prey abundance, but habitat heterogeneity and spatial subsidies (emerging aquatic insects) also showed important indirect influences. Thus, our results provided the strongest support for species–energy theory.Main conclusions Our results suggest that, by using statistical approaches that allow for analyses of both direct and indirect influences, a seemingly direct influence of area on species richness can be explained by greater energy availability on larger islands. As such, animal community patterns that seem to be in line with island biogeography theory may be primarily driven by energy availability. Our results also point to the need to consider several aspects of habitat quality (e.g. heterogeneity, NPP, prey availability and spatial subsidies) for successful management of breeding bird diversity at local spatial scales and in fragmented or insular habitats.
31.	Jønsson, Knud A., et al. (author) Biogeographical history of cuckoo‐shrikes (Aves: Passeriformes) : transoceanic colonization of Africa from Australo-Papua 2010 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 37:9, s. 1767-1781 Journal article (peer-reviewed)abstract Aim Cuckoo-shrikes and allies (Campephagidae) form a radiation of birds widely distributed in the Indo-Pacific and Africa. Recent studies on the group have been hampered by poor taxon sampling, causing inferences about systematics and biogeography to be rather speculative. With improved taxon sampling and analyses within an explicit spatiotemporal framework, we elucidate biogeographical patterns of dispersal and diversification within this diverse clade of passerine birds. Location Africa, Asia, Australo-Papua, the Pacific, the Philippines and Wallacea. Methods We use model-based phylogenetic methods (MrBayes and garli) to construct a phylogenetic hypothesis of the core Campephagidae (Campephagidae with the exclusion of Pericrocotus). The phylogeny is used to assess the biogeographical history of the group with a newly developed Bayesian approach to dispersal-vicariance analysis (Bayes-diva). We also made use of a partitioned beast analysis, with several calibration points taken from island ages, passerine mitochondrial substitution rates and secondary calibration points for passerine birds, to assess the timing of diversification and dispersal. Results We present a robust molecular phylogeny that includes all genera and 84% of the species within the core Campephagidae. Furthermore, we estimate divergence dates and ancestral area relationships. We demonstrate that Campephagidae originated in Australo-Papua with a single lineage (Pericrocotus) dispersing to Asia early. Later, there was further extensive transoceanic dispersal from Australo-Papua to Africa involving lineages within the core Campephagidae radiation. Main conclusions The phylogenetic relationships, along with the results of the ancestral area analysis and the timing of dispersal events, support a transoceanic dispersal scenario from Australo-Papua to Africa by the core Campephagidae. The sister group to core Campephagidae, Pericrocotus, dispersed to mainland Asia in the late Oligocene. Asia remained uncolonized by the core Campephagidae until the Pliocene. Transoceanic dispersal is by no means an unknown phenomenon, but our results represent a convincing case of colonization over a significant water gap of thousands of kilometres from Australo-Papua to Africa.
32.	Kalas, J A, et al. (author) Food supply and breeding occurrences : The West European population of the lekking great snipe Gallinago media (Latham, 1787) (Aves) 1997 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 24:2, s. 213-221 Journal article (peer-reviewed)
33.	Klütsch, Cornelya, et al. (author) Genetic and morphometric differentiation among island populations of two Norops lizards (Reptilia : Sauria : Polychroticlae) on independently colonized islands of the Islas de Bahia (Honduras) 2007 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 34:7, s. 1124-1135 Journal article (peer-reviewed)abstract Aim: Anole lizards (Reptilia: Sauria: Polychrotidae) display remarkable morphological and genetic differentiation between island populations. Morphological differences between islands are probably due to both adaptive (e.g. differential resource exploitation and intra- or interspecific competition) and non-adaptive differentiation in allopatry. Anoles are well known for their extreme diversity and rapid adaptive speciation on islands. The main aim of this study was to use tests of morphological and genetic differentiation to investigate the population structure and colonization history of islands of the Islas de Bahia, off the coast of Honduras. Location Five populations of Norops bicaorum and Norops lemurinus were sampled, four from islands of the Islas de Bahia and one from the mainland of Honduras. Methods Body size and weight differentiation were measured in order to test for significant differences between sexes and populations. In addition, individuals were genotyped using the amplified fragment length polymorphism technique. Bayesian model-based and assignment/exclusion methods were used to study genetic differentiation between island and mainland populations and to test colonization hypotheses. Results Assignment tests suggested migration from the mainland to the Cayos Cochinos, and from there independently to both Utila and Roatan, whereas migration between Utila and Roatan was lacking. Migration from the mainland to Utila was inferred, but was much less frequent. Morphologically, individuals from Utila appeared to be significantly different in comparison with all other localities. Significant differentiation between males of Roatan and the mainland was found in body size, whereas no significant difference was detected between the mainland and the Cayos Cochinos. Main conclusions Significant genetic and morphological differentiation was found among populations. A stepping-stone model for colonization, in combination with an independent migration to Utila and Roatan, was suggested by assignment tests and was compatible with the observed morphological differentiation.
34.	Kuneš, Petr, et al. (author) Soil phosphorous as a control of productivity and openness in temperate interglacial forest ecosystems. 2011 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 38:11, s. 2150-2164 Journal article (peer-reviewed)abstract Aim Observations of long chronosequences in forest ecosystems show that, after some millennia of build-up, biomass declines in relation to the slow depletion of soil phosphorus. Plants that dominate during this period of soil impoverishment have specialized strategies for P acquisition, including ectomycorrhiza or root clusters. We use quantitative, pollen-based reconstructions of regional vegetation in four Quaternary warm stages (Holocene, Eemian, Holsteinian, Harreskovian) to test whether inferred forest cover and productivity changes are consistent with long-term modification of soil nutrient pools.Location Southern Scandinavia (Denmark, southern Sweden).Methods The REVEALS model was used to estimate regional vegetation abundances of 25 pollen-type-equivalent taxa from pollen records of large sedimentary basins in southernmost Scandinavia. Based on the estimated regional vegetation, we then calculated time-series of Ellenberg indicator values for L (light), R (soil reaction) and N (a productivity proxy). We classified the vegetation records into distinct phases and compared these phases and the samples using hierarchical clustering and ordination.Results All three interglacials developed coniferous or mixed forests. However, pure deciduous forests were never reached during the Holsteinian, while pure coniferous forests never developed in the Holocene. Above-ground productivity was inferred to be low initially, peaking in the first third of the warm stages and then slowly declining (except during the Holocene). Dominant trees of the post-peak phases all had ectomycorrhiza as a strategy for P acquisition, indicating that easily accessible P pools had become depleted. Increases in fire regimes may have amplified the inferred final drop in productivity. Mid/late Holocene productivity changes were much influenced by agricultural activities.Main conclusions REVEALS vegetation estimates combined with Ellenberg indicator values suggest a consistent pattern in warm stages of initially rising productivity, followed by a long and slow decline. The P-acquisition strategies of dominant trees indicate that the decline reflects increasing P depletion of soils.
35.	Li, Zhonghu, et al. (author) The Pleistocene demography of an alpine juniper of the Qinghai-Tibetan Plateau : tabula rasa, cryptic refugia or something else? 2011 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 38:1, s. 31-43 Journal article (peer-reviewed)abstract Aim Numerous palaeoecological and genetic studies have shown that different tree species responded in very different ways to Pleistocene climatic oscillations. Some were forced into small refugia far from their current range, while others were able to survive in small refugia close to, or even within, their current natural range. In this study we examine the Pleistocene demography of a juniper species (Juniperus przewalskii, Cupressaceae) from the Qinghai-Tibetan Plateau. Location The Qinghai-Tibetan Plateau (QTP). Methods Eight nuclear loci were sequenced in 141 individuals from 20 natural populations distributed across the entire natural range of J. przewalskii, and coalescent analysis was used to test demographic hypotheses. Results The overall nucleotide diversity in the sample was low (pi(sil) = 0.0029), with few rare alleles and pronounced population genetic structure (F-ST = 0.181). We detected a division previously found using chloroplast DNA markers: all segregating sites in populations from the central part of the QTP appear to be a subset of those found around the edge of the plateau, confirming the relatively young age of the former. In contrast to the middle Pleistocene bottlenecks detected in boreal tree species, the coalescent-based analyses failed to reject the standard neutral model for the juniper species considered here. Main conclusions Juniperus przewalskii did not undergo marked changes in population sizes during the Pleistocene, although this species seems to have experienced recent, post-glacial expansion. This finding is largely consistent with the limited number of previous studies on conifer species of the QTP, but contradicts findings of studies on boreal species. These findings have wide implications for understanding plant species' responses to past climatic oscillations on the high-elevation QTP.
36.	Maliouchenko, O., et al. (author) Comparative phylogeography and population structure of European Betula species, with particular focus on B. pendula and B. pubescens 2007 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 34:9, s. 1601-1610 Journal article (peer-reviewed)abstract Aim To compare the population genetic structures of the haplotype-sharing species Betula pendula and B. pubescens and to draw phylogeographic inferences using chloroplast DNA markers. In particular, we tested whether B. pendula and B. pubescens exhibited the same or different phylogeographic structures. Location Western Europe and Russia. Methods In this study we used both chloroplast DNA polymerase chain reaction-restriction fragment length polymorphism and microsatellites to genotype B. pendula, B. pubescens and, to a limited extent, B. nana, in 53 populations across Eurasia. A spatialamova(samova) was used to identify major clusters within each species. Results The low level of phylogeographic structure previously observed in B. pendula was confirmed, and thesamovaanalysis retrieved only two major clusters. In contrast, seven clusters were observed in B. pubescens, although the overall level of population differentiation was similar to that of B. pendula. Main conclusions We detected a difference in the population genetic structure between the two species, despite extensive haplotype sharing. It is difficult to ascribe this finding to a single factor, but divergence in ecology between the two species may provide part of the explanation. For both species, the contribution of southern western populations to the recolonization after the Last Glacial Maximum seems to have been limited, and eastern and western European populations apparently had different histories.
37.	Malm-Renöfält, Birgitta, et al. (author) Spatial and temporal patterns of species richness in a riparian landscape 2005 In: Journal of Biogeography. - : Blackwell Publishing. - 0305-0270 .- 1365-2699. ; 32:11, s. 2025-2037 Journal article (peer-reviewed)abstract Aim: To test for control of vascular plant species richness in the riparian corridor by exploring three contrasting (although not mutually exclusive) hypotheses: (1) longitudinal patterns in riparian plant species richness are governed by local, river-related processes independent of the regional species richness, (2) riparian plant species richness is controlled by dispersal along the river (longitudinal control), and (3) the variation in riparian plant species richness mirrors variation in regional richness (lateral control).Location: The riparian zones of the free-flowing Vindel River and its surrounding river valley, northern Sweden.Methods: We used data from three surveys, undertaken at 10-year intervals, of riparian reaches (200-m stretches of riverbank) spanning the entire river. In addition, we surveyed species richness of vascular plants in the uplands adjacent to the river in 3.75-km2 large plots along the same regional gradient. We explored the relationship between riparian and upland flora, and various environmental variables. We also evaluated temporal variation in downstream patterns of the riparian flora.Results: Our results suggest that local species richness in boreal rivers is mainly a result of local, river-related processes and dispersal along the corridor. The strongest correlation between species richness and the environment was a negative one between species number and soil pH, but pH varied within a narrow range. We did not find evidence for a correlation between species richness on regional and local scales. We found that the local patterns of species richness for naturally occurring vascular plants were temporally variable, probably in response to large-scale disturbance caused by extreme floods. Most previous studies have found a unimodal pattern of species richness with peaks in the middle reaches of a river. In contrast, on two of three occasions corresponding to major flooding events, we found that the distribution of species richness of naturally occurring vascular plants resembled that of regional diversity: a monotonic decrease from headwater to coast. We also found high floristic similarity between the riparian corridor and the surrounding landscape.Main conclusions: These results suggest that local processes control patterns of riparian species richness, but that species composition is also highly dependent on the regional species pool. We argue that inter-annual variation in flood disturbance is probably the most important factor producing temporal variability of longitudinal species richness patterns.
38.	Manns, Ulrika, et al. (author) Biogeography of 'tropical Anagallis' (Myrsinaceae) inferred from nuclear and plastid DNA sequence data 2011 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 38:5, s. 950-961 Journal article (peer-reviewed)abstract Aim 'Tropical Anagallis' corresponds to one of two evolutionary lineages within the genus Anagallis L. Generally, species within this lineage have a limited distribution in (sub-)tropical regions in Africa or Madagascar. Two species, however, are endemic to South America, and exhibit a trans-Atlantic disjunction with the rest of the species within the lineage. To investigate this disjunct distribution, as well as other dispersal events, the distribution of extant taxa was used to hypothesize the ancestral area(s) of distribution. Location Africa, Madagascar, Europe and South America. Methods Dispersal-vicariance analysis (DIVA) was used to optimize distribution areas onto parsimony and Bayesian phylogenies based on sequence data from four chloroplast loci and the nuclear internal transcribed spacers (ITS). Results Parsimony analysis gave one most parsimonious tree while Bayesian analysis resulted in a collapsed node due to alternative placements of Anagallis nummularifolia Baker, endemic to Madagascar. Optimization of the present distribution using DIVA, and the most parsimonious tree and six alternative topologies of the Bayesian analysis, show an origin of the lineage in Europe as most likely, although one topology indicates a broader ancestral distribution area. Dispersal to Africa appears to have been a single event, while two parallel dispersal events seem to have resulted in the American as well as Madagascan distributions. Main conclusions The lineage 'tropical Anagallis' evolved in Europe and may have been present in the Eocene boreotropical forests, although scarcity of fossils makes assessment of age difficult. Dispersal to South America is proposed to have been via the North Atlantic land bridge, or, more likely, through transport by the North Equatorial Current. Dispersal from Europe to Africa represents a single event, while dispersal to Madagascar from mainland Africa has occurred twice.
39.	Mobley, Kenyon B, et al. (author) Population structure of the dusky pipefish (Syngnathus floridae) from the Atlantic and Gulf of Mexico, as revealed by mitochondrial DNA and microsatellite analyses 2010 In: Journal of Biogeography. - : John Wiley & Sons. - 0305-0270 .- 1365-2699. ; 37:7, s. 1363-1377 Journal article (peer-reviewed)abstract Aim To elucidate the historical phylogeography of the dusky pipefish (Syngnathus floridae) in the North American Atlantic and Gulf of Mexico ocean basins. Location Southern Atlantic Ocean and northern Gulf of Mexico within the continental United States. Methods A 394-bp fragment of the mitochondrial cytochrome b gene and a 235-bp fragment of the mitochondrial control region were analysed from individuals from 10 locations. Phylogenetic reconstruction, haplotype network, mismatch distributions and analysis of molecular variance were used to infer population structure between ocean basins and time from population expansion within ocean basins. Six microsatellite loci were also analysed to estimate population structure and gene flow among five populations using genetic distance methods (FST, Nei’s genetic distance), isolation by distance (Mantel’s test), coalescent-based estimates of genetic diversity and migration patterns, Bayesian cluster analysis and bottleneck simulations. Results Mitochondrial analyses revealed significant structuring between ocean basins in both cytochrome b (ΦST = 0.361, P < 0.0001; ΦCT = 0.312, P < 0.02) and control region (ΦST = 0.166, P < 0.0001; ΦCT = 0.128, P < 0.03) sequences. However, phylogenetic reconstructions failed to show reciprocal monophyly in populations between ocean basins. Microsatellite analyses revealed significant population substructuring between all locations sampled except for the two locations that were in closest proximity to each other (global FST value = 0.026). Bayesian analysis of microsatellite data also revealed significant population structuring between ocean basins. Coalescent-based analyses of microsatellite data revealed low migration rates among all sites. Mismatch distribution analysis of mitochondrial loci supports a sudden population expansion in both ocean basins in the late Pleistocene, with the expansion of Atlantic populations occurring more recently. Main conclusions Present-day populations of S. floridae do not bear the mitochondrial DNA signature of the strong phylogenetic discontinuity between the Atlantic and Gulf coasts of North America commonly observed in other species. Rather, our results suggest that Atlantic and Gulf of Mexico populations of S. floridae are closely related but nevertheless exhibit local and regional population structure. We conclude that the present-day phylogeographic pattern is the result of a recent population expansion into the Atlantic in the late Pleistocene, and that life-history traits and ecology may play a pivotal role in shaping the realized geographical distribution pattern of this species.
40.	Munoz-Fuentes, Violeta, et al. (author) Ecological factors drive differentiation in wolves from British Columbia 2009 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 36:8, s. 1516-1531 Journal article (peer-reviewed)abstract Aim Limited population structure is predicted for vagile, generalist species, such as the grey wolf (Canis lupus L.). Our aims were to study how genetic variability of grey wolves was distributed in an area comprising different habitats that lay within the potential dispersal range of an individual and to make inferences about the impact of ecology on population structure. Location British Columbia, Canada - which is characterized by a continuum of biogeoclimatic zones across which grey wolves are distributed - and adjacent areas in both Canada and Alaska, United States. Methods We obtained mitochondrial DNA control region sequences from grey wolves from across the province and integrated our genetic results with data on phenotype, behaviour and ecology (distance, habitat and prey composition). We also compared the genetic diversity and differentiation of British Columbia grey wolves with those of other North American wolf populations. Results We found strong genetic differentiation between adjacent populations of grey wolves from coastal and inland British Columbia. We show that the most likely factor explaining this differentiation is habitat discontinuity between the coastal and interior regions of British Columbia, as opposed to geographic distance or physical barriers to dispersal. We hypothesize that dispersing grey wolves select habitats similar to the one in which they were reared, and that this differentiation is maintained largely through behavioural mechanisms. Main conclusions The identification of strong genetic structure on a scale within the dispersing capabilities of an individual suggests that ecological factors are driving wolf differentiation in British Columbia. Coastal wolves are highly distinct and representative of a unique ecosystem, whereas inland British Columbia grey wolves are more similar to adjacent populations of wolves located in Alaska, Alberta and Northwest Territories. Given their unique ecological, morphological, behavioural and genetic characteristics, grey wolves of coastal British Columbia should be considered an Evolutionary Significant Unit (ESU) and, consequently, warrant special conservation status. If ecology can drive differentiation in a highly mobile generalist such as the grey wolf, ecology probably drives differentiation in many other species as well.
41.	Murphy, Nicholas P., et al. (author) Trapped in desert springs : phylogeography of Australian desert spring snails 2012 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 39:9, s. 1573-1582 Journal article (peer-reviewed)abstract AimWe investigate the phylogeographical history and determine the time-scaleof population divergence of hydrobiid freshwater snails (genus Trochidrobia)inhabiting groundwater springs in the Australian desert. We test the hypothesisthat divergence between geographically distinct snail populations occurredsimultaneously due to their isolation in hydrologically discrete spring systems, i.e.‘trapped in desert springs’.LocationGroundwater springs of the Great Artesian Basin (GAB) in centralAustralia.MethodsDNA sequence data from the mitochondrial cytochrome c oxidasesubunit I gene and the nuclear 28S and internal transcribed spacer rRNA geneswere used to reconstruct phylogenetic relationships within and among threespecies of Trochidrobia (Hydrobiidae): T. punicea (13 spring groups, n = 90),T. smithi (12 spring groups, n = 62) and T. minuta (2 spring groups, n = 4). Bayesian relaxed molecular clock analyses and approximate Bayesian computation were used to date lineage divergence and distinguish betweenalternative biogeographical scenarios.ResultsThe diversification of the three Trochidrobia species probably occurredbetween 2.54 and 9.3 Ma, prior to the formation of the springs c. 1 Ma.Intraspecific divergences within the two widespread species occurred after theformation and colonization of the springs. Coalescent modelling and molecularclock analyses supported a simultaneous radiation of five allopatric intraspecificsnail lineages within T. punicea (two lineages) and T. smithi (three lineages)across the GAB springs examined.Main conclusionsThe analyses support the ‘trapped in desert springs’hypothesis for the diversification of intraspecific lineages within the species T.punicea and T. smithi. This hypothesis suggests that the formation of desertsaround Lake Eyre in the early Pleistocene led to the hydrological isolation ofspring complexes in the GAB, resulting in significant molecular divergence, butno morphological divergence, of Trochidrobia snail populations.
42.	Olsen, J. L., et al. (author) The phylogeographic architecture of the fucoid seaweed Ascophyllum nodosum: an intertidal 'marine tree' and survivor of more than one glacial-interglacial cycle 2010 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 37:5, s. 842-856 Journal article (peer-reviewed)abstract Aim Ascophyllum nodosum (L.) Le Jolis is a dominant fucoid seaweed occurring along sheltered, rocky shores throughout the North Atlantic (but not in the Pacific), where it is a foundational species of the intertidal community. Its large size and vulnerability to ice-scour have led to the hypothesis that contemporary populations in the north-west Atlantic may be the result of de novo recolonization from the north-east Atlantic since the Last Glacial Maximum (LGM) (c. 20 ka). We tested this hypothesis. Location Temperate North Atlantic rocky intertidal between c. 42 and 65 degrees N latitude. Methods More than 1300 individuals from 28 populations were sampled from across the entire range of A. nodosum and genotyped for six microsatellite loci, and > 500 individuals were genotyped for two mitochondrial loci, an intergenic spacer (IGS) and the tRNA (W) gene (trnW). Population structure and historical demography were analysed in a standard population genetics and coalescence framework. Results Based on the presence of private alleles and haplotypes, we found that A. nodosum has survived on both sides of the Atlantic (since before the LGM, dating back to at least the penultimate Eemian interglacial) with similar effective population sizes and divergence times (1.2 and 0.8 Ma). Dispersal has been predominantly from Europe to North America, and there is very weak present-day population differentiation across the North Atlantic. Diversity measures provided additional support for determining the location of refugia. Main conclusions Ascophyllum nodosum was apparently little affected by the LGM, although contemporary climate change is likely to have major effects on its latitudinal distribution on both sides of the North Atlantic. It is a very long-lived species, analogous in virtually all demographic aspects to a tree - resistant to extinction but vulnerable to catastrophic events. The Brittany peninsula is a hotspot of genetic diversity worthy of conservation.
43.	Razafimandimbison, Sylvain G., et al. (author) Origin of the pantropical and nutriceutical Morinda citrifolia L. (Rubiaceae) : comments on its distribution range and circumscription 2010 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 37:3, s. 520-529 Journal article (peer-reviewed)abstract Aim Morinda citrifolia L., commercially known as noni or the Indian mulberry plant, is morphologically variable and the only widely distributed member of the pantropical genus Morinda sensu stricto (Rubiaceae). This large distribution has been attributed partly to the ability of the seeds of the large-fruited M. citrifolia L. var. citrifolia L. to be transported by oceanic drifting. This form of M. citrifolia var. citrifolia has been predicted to be the progenitor colonizer of the island endemic Morinda species. Using a phylogenetic approach and large sampling of the widespread, large-fruited M. citrifolia var. citrifolia, we assessed the potential area of origin of M. citrifolia and tested the hypothesis that the large-fruited M. citrifolia var. citrifolia is an ancestral colonizer. Location Tropics. Methods We performed Bayesian analyses of 22 species of the tribe Morindeae (including 11 individuals of the three currently recognized varieties of M. citrifolia) based on combined nrETS, nrITS, rps16 and trnT-F sequence data. Geographic origins of the studied taxa were mapped onto the Bayesian majority rule consensus tree. Results Nine sequenced individuals of M. citrifolia from diverse geographic locations formed a highly supported clade, which was sister to the Australo-Micronesian clade that included M. bracteata var. celebica and M. latibracteata. These sister clades are part of the broader Asian, arborescent Morinda clade. We found no support for the current varietal classification of M. citrifolia. Main conclusions Our analyses suggest a Micronesian origin of M. citrifolia. This implies that the large-fruited M. citrifolia var. citrifolia might well have been present in the Pacific before the arrival of the Micronesian and Polynesian ancestors from Southeast Asia. The wide distribution of this form of M. citrifolia var. citrifolia is attributed partly to the trans-oceanic dispersal of its buoyant seeds, self-pollination and its ability to produce flowers and fruits year-round. The hypothesis that the widespread, large-fruited M. citrifolia var. citrifolia is the progenitor colonizer of the island endemic Morinda species is inconsistent with its derived position within the Asian, arborescent Morinda clade and with the fact that the nine sampled individuals of M. citrifolia form a clade.
44.	Roberge, Jean-Michel (author) Energy density and its variation in space limit species richness of boreal forest birds 2012 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 39, s. 1462-1472 Journal article (peer-reviewed)abstract Aim An areas ability to support species may be dependent not only on the total amount of available energy it contains but also on energy density (i.e. available energy per unit area). Acknowledging these two aspects of energy availability may increase mechanistic understanding of how increased energy availability results in increased species richness. We studied the relationship between energy density, its variation in space and boreal forest bird species richness and investigated two possible mechanisms: (1) metabolic constraints of organisms, and (2) increased resource availability for specialists. Location Protected areas in Finlands boreal forest. Methods We tested whether bird species richness was best determined by total energy availability in an area or by energy density and its variation within the area, before and after including bird abundance in the models. We evaluated two main explanatory variables: tree growth reflecting the rate of energy production and tree volume as a measure of biomass. In addition, we modelled individual species responses to energy density and its variation, and evaluated the prediction of the metabolic constraints hypothesis that small species are limited by energy density whereas large species are limited by total energy availability in the area. Results Energy density and its variation were good predictors of species richness: together with abundance they explained 84% of variation in species richness (compared with 74% for abundance alone). Pure metabolic constraints were unlikely to explain this relationship. Instead, the mechanism probably involved increased habitat heterogeneity benefiting specialist species. Total energy availability was also an important factor determining species richness but its effect was indirect via abundance. Main conclusions Our results corroborate the importance of energy availability as a driver of species richness in forest bird communities, and they indicate that energy density and its variation in the landscape strongly influence species richness even after accounting for abundance.
45.	Sanmartin, Isabel, et al. (author) West Wind Drift revisited : testing for directional dispersal in the Southern Hemisphere using event-based tree fitting 2007 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 34:3, s. 398-416 Journal article (peer-reviewed)abstract Aim Recent studies suggest that if constrained by prevailing wind or ocean currents dispersal may produce predictable, repeated distribution patterns. Dispersal mediated by the West Wind Drift (WWD) and Antarctic Circumpolar Current (AAC) has often been invoked to explain the floristic similarities of Australia, South America and New Zealand. If these systems have been important dispersal vectors then eastward dispersal - from Australia to New Zealand and the western Pacific to South America - is expected to predominate. We investigate whether phylogenies for Southern Hemisphere plant groups provide evidence of historical dispersal asymmetry and more specifically whether inferred asymmetries are consistent with the direction of the WWD/AAC. Location Southern Hemisphere. Methods We assembled a data set of 23 published phylogenies for plant groups that occur in New Zealand, Australia and/or South America. We used parsimony-based tree fitting to infer the number and direction of dispersals within each group. Observed dispersal asymmetries were tested for significance against a distribution of expected values. Results Our analyses suggest that dispersal has played a major role in establishing present distributions and that there are significant patterns of asymmetry in Southern Hemisphere dispersal. Consistent with the eastward direction of the WWD/ACC, dispersal from Australia to New Zealand was inferred significantly more often than in the reverse direction. No significant patterns of dispersal asymmetry were found between the western Pacific landmasses and South America. However, eastward dispersal was more frequently inferred between Australia and South America, while for New Zealand-South American events westward dispersal was more common. Main Conclusions Our results suggest that eastward circumpolar currents have constrained the dispersal of plants between Australia and New Zealand. However, the WWD/ACC appear to have had less of an influence on dispersal between the western Pacific landmasses and South America. This observation may suggest that differences in dispersal mechanism are important - direct wind or water dispersal vs. stepping-stone dispersal along the Antarctic coast. While our analyses provide useful preliminary insights into dispersal asymmetry in the Southern Hemisphere we will need larger data sets and additional methodological advances in order to test fully these dispersal patterns and infer processes from phylogenetic data.
46.	Semerikova, Svetlana A., et al. (author) Post-glacial history and introgression in Abies (Pinaceae) species of the Russian Far East inferred from both nuclear and cytoplasmic markers 2011 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 38:2, s. 326-340 Journal article (peer-reviewed)abstract Aim The main aim of the present study is to infer the post-glacial history of Abies species from north-east Asia and to test the hypotheses that coastal Abies populations suffered less from climatic fluctuations during Pleistocene glacial periods than their more continental counterparts, and that Sakhalin was a major area of introgression. Location Natural ranges of the fir species Abies nephrolepis, Abies sachalinensis and Abies holophylla in the Russian Far East, and of Abies gracilis, which is endemic to the Kamchatka Peninsula. Methods Nineteen populations were sampled for allozyme analysis. Seventeen of these populations were also screened for variation at two paternally inherited chloroplast DNA microsatellite loci (cpSSR) and variation at one maternally inherited mitochondrial marker (nad4-3/4). Finally a subset of 11 populations was analysed with amplified fragment length polymorphism (AFLP). Comparisons were made with already available Abies sibirica data. For all sets of markers, we estimated genetic diversity and differentiation using an analysis of molecular variance (AMOVA). Population clustering was assessed with a Bayesian approach implemented in structure v.2.3. Results Among the three major species, A. sibirica, A. nephrolepis and A. sachalinensis, A. sachalinensis demonstrated the highest cytoplasmic and nuclear diversity and the most continental species, A. sibirica, the lowest. Both nuclear and mitochondrial DNA markers revealed the presence of a transitional zone on Sakhalin Island between A. nephrolepis and A. sachalinensis of south Sakhalin. The structure analysis delivered very clear results confirming the admixed origin of A. sachalinensis, with a genetic contribution from A. nephrolepis. No variation in cytoplasmic markers was found in A. gracilis, suggesting the occurrence of a recent bottleneck. Main conclusions There is a clear reduction of genetic diversity in Abies species from the Pacific coast into the continent. The higher diversity in A. sachalinensis could have two causes: a larger effective population size in the islands due to relatively stable climatic conditions and consequently less pronounced demographic fluctuations in population size and/or hybridization with continental and Japanese populations. Sakhalin Island is a major transitional zone for conifer species. Finally, the fir from Kamchatka, A. gracilis, should be regarded as a separate species closely related to the A. nephrolepis-A. sachalinensis complex.
47.	Smedmark, Jenny E. E., et al. (author) Divergence time uncertainty and historical biogeography reconstruction - an example from Urophylleae (Rubiaceae) 2010 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 37:12, s. 2260-2274 Journal article (peer-reviewed)abstract Aim When hypotheses of historical biogeography are evaluated, age estimates of individual nodes in a phylogeny often have a direct impact on what explanation is concluded to be most likely. Confidence intervals of estimated divergence times obtained in molecular dating analyses are usually very large, but the uncertainty is rarely incorporated in biogeographical analyses. The aim of this study is to use the group Urophylleae, which has a disjunct pantropical distribution, to explore how the uncertainty in estimated divergence times affects conclusions in biogeographical analysis. Two hypotheses are evaluated: (1) long-distance dispersal from Africa to Asia and the Neotropics, and (2) a continuous distribution in the boreotropics, probably involving migration across the North Atlantic Land Bridge, followed by isolation in equatorial refugia. Location Tropical and subtropical Asia, tropical Africa, and central and southern tropical America. Methods This study uses parsimony and Bayesian phylogenetic analyses of chloroplast DNA and nuclear ribosomal DNA data from 56 ingroup species, beast molecular dating and a Bayesian approach to dispersal-vicariance analysis (Bayes-DIVA) to reconstruct the ancestral area of the group, and the dispersal-extinction-cladogenesis method to test biogeographical hypotheses. Results When the two models of geographic range evolution were compared using the maximum likelihood (ML) tree with mean estimates of divergence times, boreotropical migration was indicated to be much more likely than long-distance dispersal. Analyses of a large sample of dated phylogenies did, however, show that this result was not consistent. The age estimate of one specific node had a major impact on likelihood values and on which model performed best. The results show that boreotropical migration provides a slightly better explanation of the geographical distribution patterns of extant Urophylleae than long-distance dispersal. Main conclusions This study shows that results from biogeographical analyses based on single phylogenetic trees, such as a ML or consensus tree, can be misleading, and that it may be very important to take the uncertainty in age estimates into account. Methods that account for the uncertainty in topology, branch lengths and estimated divergence times are not commonly used in biogeographical inference today but should definitely be preferred in order to avoid unwarranted conclusions.
48.	Sundberg, S., et al. (author) Colonization of Sphagnum on land uplift islands in the Baltic Sea : time, area, distance and life history 2006 In: Journal of Biogeography. - Uppsala Univ, Evolutionary Biol Ctr, Dept Plant Ecol, SE-75236 Uppsala, Sweden. : Wiley. - 0305-0270 .- 1365-2699. ; 33:8, s. 1479-1491 Journal article (peer-reviewed)abstract Aim: To test whether species richness of Sphagnum mosses on islands in a land uplift archipelago is related to island age, area or connectivity, and whether the frequency of different species can be predicted by their life history and autecology. Location: The northern Stockholm archipelago in the Baltic Sea, east-central Sweden, with a current land uplift rate of 4.4 mm year(-1). Methods: We sampled 17 islands differing in area (0.55-55 ha), height (3.6-18 m, representing c. 800-4000 years of age) and distance from mainland (1.6-41 km). For each Sphagnum patch we measured area, height above sea level, horizontal distance from the shore and shading from vascular plants. Factors affecting island species richness, species frequency and habitats on the islands were tested by stepwise regressions. Species frequency was tested on nine life history and autecological variables, including estimated abundance and spore output on the mainland, habitat preference and distribution. Results: We recorded 500 patches of 19 Sphagnum species, distributed in 83 rock pools on 14 islands. Island species richness correlated positively with island area and with degree of shelter by surrounding islands, while distance from the mainland, connectivity, height or age did not add to the model. Species frequency (number of colonized islands and rock pools) was mainly predicted by spore output on the mainland and by habitat preference (swamp forest species were more frequent than others), while spore size, for example, did not add to the model. Species differed in mean height above and horizontal distance from the shore, area of occupied rock pools and in the degree of shading of patches. The mean horizontal distance from the shore and the area of occupied rock pools correlated positively with the normal growth position above the water table among species. Spore capsules were found in only 2% of patches, mostly in the bisexual Sphagnum fimbriatum. Main conclusions: The presence of Sphagnum in the Stockholm archipelago seems to be governed by regional spore production and habitat demands. Sphagnum does not appear to be dispersal limited at distances up to 40 km and time spans of centuries. Species with a high regional spore output have had a higher colonization rate, which, together with the rarity of spore capsules on the islands, indicate the mainland as a source for colonization rather than dispersal among islands. Swamp forest species seem more tolerant to the island conditions (summer droughts and some salt spray) than open mire species. The different distances from the sea occupied by the species indicate a slow, continuous succession and species replacement towards the island interior as islands are being uplifted and thus expand in area. This partly explains why larger islands harbour more species. Our results thus support some of the island biogeographical theories related to the species-area relationship.
49.	Thorsson, A. E. Th., et al. (author) Introgression and phylogeography of Betula nana (diploid), B-pubescens (tetraploid) and their triploid hybrids in Iceland inferred from cpDNA haplotype variation 2010 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 37:11, s. 2098-2110 Journal article (peer-reviewed)abstract Aim The objective was to find direct genetic evidence supporting introgressive hybridization between tetraploid tree birch (Betula pubescens) and diploid dwarf birch (B. nana), via triploid hybrids, and to investigate an association between the introgression and phylogeographical distribution of Icelandic birch. Location Samples were collected from 463 trees in 12 woodlands in Iceland and eight locations in Norway, Sweden, Scotland and Greenland. Methods Ploidy status of individual trees was determined by chromosome counting. Variation in the chloroplast genome was assessed using polymerase chain reaction-restriction fragment length polymorphism. The geographical distribution of the haplotypes was mapped. The haplotype variation and introgression ratios (IG) were analysed statistically. Results Thirteen haplotypes were identified among Icelandic samples. The most common haplotype (T, 49% occurrence) was present in all ploidy groups and in all woodlands. All common haplotypes were shared between the triploid group and the parental species, indicating introgressive hybridization. This was supported by the statistical analysis of IG indices and the variation components. Considerable differences existed among samples, shaped by isolation by distance and local introgression. An east-west phylogeographical distribution in Iceland was observed. Main conclusions Despite extensive introgression across species and ploidy levels, a biogeographical pattern has been observed, and this may indicate different population histories or multiple origins of Icelandic birch. The chloroplast haplotype diversity found in Iceland resembles that found in birch populations from northern Scandinavia.
50.	Valiranta, Minna, et al. (author) Scattered late-glacial and early Holocene tree populations as dispersal nuclei for forest development in north-eastern European Russia 2011 In: Journal of Biogeography. - : Wiley. - 0305-0270 .- 1365-2699. ; 38:5, s. 922-932 Journal article (peer-reviewed)abstract Aim Concepts about patterns and rates of post-glacial tree population migration are changing as a result of the increasing amount of palaeobotanical information being provided by macroscopic plant remains. Here we combine macrofossil, pollen and stomata records from five sites in north-eastern European Russia and summarize the results for the late-glacial-early Holocene transition. The late-glacial-early Holocene transition encompasses the first indications of trees (tree-type Betula, Picea abies, Abies sibirica and Larix sibirica) and subsequent forest development. Considerable time-lags between the first macrobotanical and/or stomata finds of spruce (Picea abies) and the establishment of a closed forest are reconsidered. Location Pechora basin, north-eastern European Russia. Methods We used plant macrofossil, stomata, pollen and radiocarbon analyses to reconstruct late-glacial and early Holocene tree establishment and forest development. The data were derived from lake sediment and peat archives. Results Palaeobotanical data reveal an early Holocene presence (11,500-10,000 cal. yr bp) of arboreal taxa at all five sites. One site presently located in the northernmost taiga zone, shows the presence of spruce and reproducing tree birch during the late-glacial. Given the current view of post-glacial population dynamics and migration rates, it seems likely that the source area of these early tree populations in north-eastern European Russia was not located in southern Europe but that these populations had local origins. Results thus support the emerging view that the first post-glacial population expansions in non-glaciated regions at high latitudes do not reflect migration from the south but were a result of an increase in the size and density of small persisting outlying tree populations. Main conclusions Results suggest that the area east of the margin of the Scandinavian ice sheet to the Ural Mountains had isolated patches of trees during the late-glacial and early Holocene and that these small populations acted as initial nuclei for population expansion and forest development in the early Holocene.

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