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  • 1301. Olsson, Urban
    et al.
    Irestedt, Martin
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Sangster, George
    Naturhistoriska riksmuseet, Enheten för zoologi.
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Alström, Per
    Systematic revision of the avian family Cisticolidae based on a multi-locus phylogeny of all genera.2013Inngår i: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 66, nr 3, s. 790-9Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The avian taxon Cisticolidae includes c. 110 species which are distributed throughout the tropical and subtropical parts of the Old World. We estimated the phylogeny of 47 species representing all genera assumed to be part of Cisticolidae based on sequence data from two mitochondrial and two nuclear markers, in total 3495bp. Bayesian inference and maximum likelihood analyses resulted in a generally well-supported phylogeny which clarified the position of several previously poorly known taxa. The placement of Drymocichla, Malcorus, Micromacronus, Oreophilais, Phragmacia, Phyllolais, Poliolais and Urorhipis in Cisticolidae is corroborated, whereas Rhopophilus and Scotocerca are removed from Cisticolidae. Urorhipis and Heliolais are placed in the genus Prinia whereas Prinia burnesii is shown to be part of Timaliidae, and is placed in the genus Laticilla. Although not recovered by all single loci independently, four major clades were identified within Cisticolidae, and one of these is here described as a new taxon (Neomixinae).

  • 1302.
    Omrak, Ayca
    et al.
    Stockholm Univ, Dept Archaeol & Class Studies, Lilla Frescativagen 7, S-11418 Stockholm, Sweden..
    Günther, Torsten
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Valdiosera, Cristina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi. La Trobe Univ, Dept Archaeol Environm & Community Planning, Melbourne, Vic 3086, Australia..
    Svensson, Emma M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi. Swedish Univ Agr Sci, Dept Anim Breeding & Genet, Ullsvag 26, S-75007 Uppsala, Sweden..
    Malmström, Helena Jankovic
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Kiesewetter, Henrike
    Univ Tubingen, Project Troia, Inst Prehist Early Hist & Medieval Archaeol, Schloss Burgsteige 11, D-72070 Tubingen, Germany..
    Aylward, William
    Univ Wisconsin, Ctr Biotechnol, 1220 Linden Dr, Madison, WI 53706 USA.;Univ Wisconsin, Dept Class & Ancient Near Eastern Studies, 1220 Linden Dr, Madison, WI 53706 USA..
    Stora, Jan
    Stockholm Univ, Dept Archaeol & Class Studies, Lilla Frescativagen 7, S-11418 Stockholm, Sweden..
    Jakobsson, Mattias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Gotherström, Anders
    Stockholm Univ, Dept Archaeol & Class Studies, Lilla Frescativagen 7, S-11418 Stockholm, Sweden..
    Genomic Evidence Establishes Anatolia as the Source of the European Neolithic Gene Pool2016Inngår i: Current Biology, ISSN 0960-9822, E-ISSN 1879-0445, Vol. 26, nr 2, s. 270-275Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Anatolia and the Near East have long been recognized as the epicenter of the Neolithic expansion through archaeological evidence. Recent archaeogenetic studies on Neolithic European human remains have shown that the Neolithic expansion in Europe was driven westward and northward by migration from a supposed Near Eastern origin [1-5]. However, this expansion and the establishment of numerous culture complexes in the Aegean and Balkans did not occur until 8,500 before present (BP), over 2,000 years after the initial settlements in the Neolithic core area [6-9]. We present ancient genome-wide sequence data from 6,700-year-old human remains excavated from a Neolithic context in Kumtepe, located in northwestern Anatolia near the well-known (and younger) site Troy [10]. Kumtepe is one of the settlements that emerged around 7,000 BP, after the initial expansion wave brought Neolithic practices to Europe. We show that this individual displays genetic similarities to the early European Neolithic gene pool and modern-day Sardinians, as well as a genetic affinity to modern-day populations from the Near East and the Caucasus. Furthermore, modern-day Anatolians carry signatures of several admixture events from different populations that have diluted this early Neolithic farmer component, explaining why modern-day Sardinian populations, instead of modern-day Anatolian populations, are genetically more similar to the people that drove the Neolithic expansion into Europe. Anatolia's central geographic location appears to have served as a connecting point, allowing a complex contact network with other areas of the Near East and Europe throughout, and after, the Neolithic.

  • 1303.
    Onut-Brännström, Ioana
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Ament-Velásquez, Sandra Lorena
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Hiltunen, Markus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Resl, Philipp
    Vanderpool, Dan
    Yamamoto, Yoshikazu
    Spribille, Toby
    Scofield, Douglas G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Johannesson, Hanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Constraints to sex by a single mating type? Genomic and population analyses reveal insight into the reproductive biology of ThamnoliaManuskript (preprint) (Annet vitenskapelig)
  • 1304.
    Onuţ-Brännström, Ioana
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Benjamin, Mitchell
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Scofield, Douglas G.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Starri, Heiðmarsson
    Icelandic Institute of Natural History, Borgir Nordurslod, Iceland.
    Andersson, Martin G.I.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Lindström, Eva S.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Limnologi.
    Johannesson, Hanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Sharing of photobionts in sympatric populations of Thamnolia and Cetraria lichens: evidence from high-throughput sequencing2018Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, artikkel-id 4406Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, we explored the diversity of green algal symbionts (photobionts) in sympatric populations of the cosmopolitan lichen-forming fungi Thamnolia and Cetraria. We sequenced with both Sanger and Ion Torrent High-Throughput Sequencing technologies the photobiont ITS-region of 30 lichen thalli from two islands: Iceland and Öland. While Sanger recovered just one photobiont genotype from each thallus, the Ion Torrent data recovered 10–18 OTUs for each pool of 5 lichen thalli, suggesting that individual lichens can contain heterogeneous photobiont populations. Both methods showed evidence for photobiont sharing between Thamnolia and Cetraria on Iceland. In contrast, our data suggest that on Öland the two mycobionts associate with distinct photobiont communities, with few shared OTUs revealed by Ion Torrent sequencing. Furthermore, by comparing our sequences with public data, we identified closely related photobionts from geographically distant localities. Taken together, we suggest that the photobiont composition in Thamnolia and Cetraria results from both photobiont-mycobiont codispersal and local acquisition during mycobiont establishment and/or lichen growth. We hypothesize that this is a successful strategy for lichens to be flexible in the use of the most adapted photobiont for the environment.

  • 1305.
    Onuţ-Brännström, Ioana
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Tibell, Leif
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    Johannesson, Hanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi.
    A worldwide phylogeography of the whiteworm lichens Thamnolia reveals three lineages with distinct habitats and evolutionary histories2017Inngår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 7, nr 10, s. 3602-3615Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Thamnolia is a lichenized fungus with an extremely wide distribution, being encountered in arctic and alpine environments in most continents. In this study, we used molecular markers to investigate the population structure of the fungal symbiont and the associated photosynthetic partner of Thamnolia. By analyzing molecular, morphological, and chemical variation among 253 specimens covering the species distribution range, we revealed the existence of three mycobiont lineages. One lineage (Lineage A) is confined to the tundra region of Siberia and the Aleutian Islands, a second (Lineage B) is found in the high alpine region of the Alps and the Carpathians Mountains, and a third (Lineage C) has a worldwide distribution and covers both the aforementioned ecosystems. Molecular dating analysis indicated that the split of the three lineages is older than the last glacial maximum, but the distribution ranges and the population genetic analyses suggest an influence of last glacial period on the present-day population structure of each lineage. We found a very low diversity of Lineage B, but a higher and similar one in Lineages A and C. Demographic analyses suggested that Lineage C has its origin in the Northern Hemisphere, possibly Scandinavia, and that it has passed through a bottleneck followed by a recent population expansion. While all three lineages reproduce clonally, recombination tests suggest rare or past recombination in both Lineages A and C. Moreover, our data showed that Lineage C has a comparatively low photobiont specificity, being found associated with four widespread Trebouxia lineages (three of them also shared with other lichens), while Lineages A and B exclusively harbor T. simplex s. lat. Finally, we did not find support for the recognition of taxa in Thamnolia based on either morphological or chemical characters.

  • 1306. Ord, Terry
    et al.
    Klomp, Danielle
    Garcia-Porta, Joan
    Hagman, Mattias
    University of New South Wales, Kensington, Australia.
    Repeated evolution of exaggerated dewlaps and other throat morphology in lizards.2015Inngår i: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 28, s. 1948-1964Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The existence of elaborate ornamental structures in males is often assumed to reflect the outcome of female mate choice for showy males. However, female mate choice appears weak in many iguanian lizards, but males still exhibit an array of ornament-like structures around the throat. We performed a phylogenetic comparative study to assess whether these structures have originated in response to male–male competition or the need for improved signal efficiency in visually difficult environments. We found little evidence for the influence of male–male competition. Instead, forest species were more likely to exhibit colourful throat appendages than species living in open habitats, suggesting selection for signal efficiency. On at least three independent occasions, throat ornamentation has become further elaborated into a large, conspicuously coloured moving dewlap. Although the function of the dewlap is convergent, the underlying hyoid apparatus has evolved very differently, revealing the same adaptive outcome has been achieved through multiple evolutionary trajectories. More generally, our findings highlight that extravagant, ornament-like morphology can evolve in males without the direct influence of female mate choice and that failure to consider alternative hypotheses for the evolution of these structures can obscure the true origins of signal diversity among closely related taxa.

  • 1307.
    Orizaola, German
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Laurila, Anssi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Developmental plasticity increases at the northern range margin in a warm-dependent amphibian2016Inngår i: Evolutionary Applications, ISSN 1752-4571, E-ISSN 1752-4571, Vol. 9, nr 3, s. 471-478Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Accurate predictions regarding how climate change affects species and populations are crucial for the development of effective conservation measures. However, models forecasting the impact of climate change on natural environments do not often consider the geographic variation of an organism's life history. We examined variation in developmental plasticity to changing temperature in the pool frog (Pelophylax lessonae) across its distribution by studying populations from central areas (Poland), edge populations (Latvia) and northern marginal populations (Sweden). Relative to central and edge populations, northern populations experience lower and less variable temperature and fewer episodes of warm weather during larval development. Plasticity in larval life-history traits was highest at the northern range margin: larvae from marginal populations shortened larval period and increased growth rate more than larvae from central and edge populations when reared at high temperature. Maintaining high growth and development under the scarce spells of warm weather is likely adaptive for high-latitude populations. The detection of high levels of developmental plasticity in isolated, marginal populations suggests that they may be better able to respond to the temperature regimes expected under climate change than often predicted, reflecting the need to incorporate geographic variation in life-history traits into models forecasting responses to environmental change.

  • 1308.
    Orraryd, Daniel
    et al.
    Linköpings universitet, Institutionen för samhälls- och välfärdsstudier, Lärande, Estetik, Naturvetenskap (LEN). Linköpings universitet, Utbildningsvetenskap.
    Tibell, Lena A.E.
    Linköpings universitet, Institutionen för teknik och naturvetenskap, Medie- och Informationsteknik. Linköpings universitet, Tekniska fakulteten.
    Creative evolution: Students generating stop-motion animations of evolutionary change2015Konferansepaper (Fagfellevurdert)
    Abstract [en]

    iagrams have been used to visualize evolutionary relationships for more than 150 years, and are today readily found in many areas such as textbooks, media, museums and the scientific literature. The tree of life metaphor, where the diagram takes the form of an organic vertical tree has been used almost as long and is still used to a high degree in textbooks and at museums. Despite this high prevalence the instructional needed to develop tree-thinking abilities are often lacking, potentially leading to interpretational misconceptions of the evolutionary concepts presented.

    In this study 5 exhibitions with evolutionary content in natural science museums in the Nordic countries have been analysed in order to understand how evolutionary tree diagrams are incorporated in these exhibitions, what design is used and what instructional support is available to the visitor. A multi-modal social semiotic approach was used, where 3 functional levels were analysed together in order to assess the meaning making potential of the evolutionary trees in these exhibitions; i) content, representational process and design. ii) instruction and interactivity. iii) spatial and organizational composition. The analyses show a wide range of communication strategies; reaching from the evolutionary tree diagrams having a pivotal role in the exhibition narrative to being placed purely in the margin with no explicit connection to the overall evolutionary content. The instructional support is in many cases lacking but is sometimes incorporated in the presentational text of specific parts of the evolutionary tree, and the design ranges from tree of life type iconic visualisations to highly abstract renderings. Overall the evolutionary tree as a visual tool to communicate important evolutionary concepts seems to be used to a high degree but important aspects in order to better afford scientific correct interpretations of the trees are sometimes lacking.

  • 1309.
    Orsucci, Marion
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution. Univ Montpellier, Montpellier SupAgro, CBGP, INRA,CIRAD,IRD, Montpellier, France;Univ Montpellier, INRA, DGIMI, Montpellier, France.
    Audiot, P.
    Univ Montpellier, Montpellier SupAgro, CBGP, INRA,CIRAD,IRD, Montpellier, France.
    Nidelet, S.
    Univ Montpellier, Montpellier SupAgro, CBGP, INRA,CIRAD,IRD, Montpellier, France.
    Dorkeld, F.
    Univ Montpellier, Montpellier SupAgro, CBGP, INRA,CIRAD,IRD, Montpellier, France.
    Pommier, A.
    Univ Montpellier, Montpellier SupAgro, CBGP, INRA,CIRAD,IRD, Montpellier, France.
    Vabre, M.
    INRA, DIASCOPE, Mauguio, France.
    Severac, D.
    MGX Montpellier GenomiX, Inst Genom Fonct, F-34094 Montpellier 5, France.
    Rohmer, M.
    MGX Montpellier GenomiX, Inst Genom Fonct, F-34094 Montpellier 5, France.
    Gschloessl, B.
    Univ Montpellier, Montpellier SupAgro, CBGP, INRA,CIRAD,IRD, Montpellier, France.
    Streiff, R.
    Univ Montpellier, Montpellier SupAgro, CBGP, INRA,CIRAD,IRD, Montpellier, France;Univ Montpellier, INRA, DGIMI, Montpellier, France.
    Transcriptomic response of female adult moths to host and non-host plants in two closely related species2018Inngår i: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 18, artikkel-id 145Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background: Divergent selection has been shown to promote speciation in many taxa and especially in phytophagous insects. In the Ostrinia species complex, the European corn borer (ECB) and adzuki bean borer (ABB) are two sibling species specialized to different host plants. The first is a well-known maize pest, whereas the second is a polyphagous species associated with various dicotyledons. Their specialization to host plants is driven by morphological, behavioral and physiological adaptations. In particular, previous studies have shown that ECB and ABB display marked behavior with regard to plant choice during oviposition, involving specific preference and avoidance mechanisms. In this study, our goal was to identify the mechanisms underlying this host-plant specialization in adult females through an analysis of their gene expression. We assembled and annotated a de novo reference transcriptome and measured differences in gene expression between ECB and ABB females, and between environments. We related differentially expressed genes to host preference behavior, and highlighted the functional categories involved. We also conducted a specific analysis of chemosensory genes, which are considered to be good candidates for host recognition before oviposition. Results: We recorded more differentially expressed genes in ECB than in ABB samples, and noticed that the majority of genes potentially involved in the host preference were different between the two species. At the functional level, the response to plant environment in adult females involved many processes, including the metabolism of carbohydrates, lipids, proteins, and amino acids; detoxification mechanisms and immunity; and the chemosensory repertoire (as expected). Until now, most of the olfactory receptors described in Ostrinia spp. had been tested for their putative role in pheromone recognition by males. Here we observed that one specific olfactory receptor was clearly associated with ECB's discrimination between maize and mugwort conditions, highlighting a potential new candidate involved in plant odor discrimination in adult females. Conclusions: Our results are a first step toward the identification of candidate genes and functions involved in chemosensory processes, carbohydrate metabolism, and virus and retrovirus dynamics. These candidates provide new avenues for research into understanding the role of divergent selection between different environments in species diversification.

  • 1310.
    Osathanunkul, Maslin
    et al.
    Chiang Mai Univ, Fac Sci, Dept Biol, Chiang Mai 50200, Thailand..
    Suwannapoom, Chatmongkon
    Chinese Acad Sci, Kunming Inst Zool, State Key Lab Genet Resources & Evolut, Kunming 650223, Peoples R China.;Chinese Acad Sci, Kunming Inst Zool, Yunnan Lab Mol Biol Domest Anim, Kunming 650223, Peoples R China.;Chiang Mai Univ, Sci & Technol Res Inst, Chiang Mai 50200, Thailand..
    Ounjai, Sarawut
    Chiang Mai Univ, Fac Sci, Dept Biol, Chiang Mai 50200, Thailand..
    Rora, Jantarika A.
    Chiang Mai Univ, Fac Sci, Dept Biol, Chiang Mai 50200, Thailand..
    Madesis, Panagiotis
    Ctr Res & Technol Hellas, Inst Appl Biosci, Thessaloniki, Greece..
    de Boer, Hugo
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Systematisk biologi. Univ Oslo, Nat Hist Museum, NO-0318 Oslo, Norway..
    Refining DNA Barcoding Coupled High Resolution Melting for Discrimination of 12 Closely Related Croton Species2015Inngår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, nr 9, artikkel-id e0138888Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    DNA barcoding coupled high resolution melting (Bar-HRM) is an emerging method for species discrimination based on DNA dissociation kinetics. The aim of this work was to evaluate the suitability of different primer sets, derived from selected DNA regions, for Bar-HRM analysis of species in Croton (Euphorbiaceae), one of the largest genera of plants with over 1,200 species. Seven primer pairs were evaluated (matK, rbcL1, rbcL2, rbcL3, rpoC, trnL and ITS1) from four plastid regions, matK, rbcL, rpoC, and trnL, and the nuclear ribosomal marker ITS1. The primer pair derived from the ITS1 region was the single most effective region for the identification of the tested species, whereas the rbcL1 primer pair gave the lowest resolution. It was observed that the ITS1 barcode was the most useful DNA barcoding region overall for species discrimination out of all of the regions and primers assessed. Our Bar-HRM results here also provide further support for the hypothesis that both sequence and base composition affect DNA duplex stability.

  • 1311. Ostersetzer-Biran, Oren
    et al.
    Lane, Nick
    Pomiankowski, Andrew
    Burton, Ron
    Arnqvist, Göran
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Filipovska, Aleksandra
    Huchon, Dorothee
    Mishmar, Dan
    The First Mitochondrial Genomics and Evolution SMBE-Satellite Meeting: A New Scientific Symbiosis2017Inngår i: Genome Biology and Evolution, ISSN 1759-6653, E-ISSN 1759-6653, Vol. 9, nr 11, s. 3054-3058Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The central role of the mitochondrion for cellular and organismal metabolism is well known, yet its functional role in evolution has rarely been featured in leading international conferences. Moreover, the contribution of mitochondrial genetics to complex disease phenotypes is particularly important, and although major advances have been made in the field of genomics, mitochondrial genomic data have in many cases been overlooked. Accumulating data and new knowledge support a major contribution of this maternally inherited genome, and its interactions with the nucleus, to both major evolutionary processes and diverse disease phenotypes. These advances encouraged us to assemble the first Mitochondrial Genomics and Evolution (MGE) meeting-an SMBE satellite and Israeli Science foundation international conference (Israel, September 2017). Here, we report the content and outcome of the MGE meeting

  • 1312.
    Otto, Sarah P.
    et al.
    Univ British Columbia, Dept Zool, Vancouver, BC V6T 1Z4, Canada.;Univ British Columbia, Biodivers Res Ctr, Vancouver, BC V6T 1Z4, Canada..
    Scott, Michael F.
    Univ British Columbia, Biodivers Res Ctr, Vancouver, BC V6T 1Z4, Canada.;Univ British Columbia, Dept Bot, Vancouver, BC V6T 1Z4, Canada..
    Immler, Simone
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Evolution of haploid selection in predominantly diploid organisms2015Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 112, nr 52, s. 15952-15957Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Diploid organisms manipulate the extent to which their haploid gametes experience selection. Animals typically produce sperm with a diploid complement of most proteins and RNA, limiting selection on the haploid genotype. Plants, however, exhibit extensive expression in pollen, with actively transcribed haploid genomes. Here we analyze models that track the evolution of genes that modify the strength of haploid selection to predict when evolution intensifies and when it dampens the "selective arena" within which male gametes compete for fertilization. Considering deleterious mutations, evolution leads diploid mothers to strengthen selection among haploid sperm/pollen, because this reduces the mutation load inherited by their diploid offspring. If, however, selection acts in opposite directions in haploids and diploids ("ploidally antagonistic selection"), mothers evolve to reduce haploid selection to avoid selectively amplifying alleles harmful to their offspring. Consequently, with maternal control, selection in the haploid phase either is maximized or reaches an intermediate state, depending on the deleterious mutation rate relative to the extent of ploidally antagonistic selection. By contrast, evolution generally leads diploid fathers to mask mutations in their gametes to the maximum extent possible, whenever masking (e.g., through transcript sharing) increases the average fitness of a father's gametes. We discuss the implications of this maternal-paternal conflict over the extent of haploid selection and describe empirical studies needed to refine our understanding of haploid selection among seemingly diploid organisms.

  • 1313. Otálora, Monica A.G.
    et al.
    Martínez, I
    Aragón, G
    Wedin, Mats
    Naturhistoriska riksmuseet, Enheten för botanik.
    Species delimitation and phylogeography of the Pectenia species-complex: a misunderstood case in species-pairs in lichenized fungi, where reproduction mode does not delimit lineages.2017Inngår i: Fungal Biology, ISSN 1878-6146, E-ISSN 1878-6162, Vol. 121, s. 222-233-Artikkel i tidsskrift (Fagfellevurdert)
  • 1314.
    Outomuro, David
    et al.
    Biología de Organismos y Sistemas, University of Oviedo.
    Bokma, Folmer
    Department of Ecology and Environmental Science, Umeå University.
    Johansson, Frank
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Populationsbiologi och naturvårdsbiologi.
    Hind wing shape evolves faster than front wing shape in Calopteryx damselflies2012Inngår i: Evolutionary biology, ISSN 0071-3260, E-ISSN 1934-2845, Vol. 39, nr 1, s. 116-125Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wing shape has been shown in a variety of species to be influenced by natural and sexual selection. In damselflies, front- and hind wings can beat independently, and functional differentiation may occur. Males of Calopteryx damselflies show species-specific nuptial flights that differ in colour signalling with the hind wings. Therefore, hind wing shape and colour may evolve in concert to improve colour display, independent of the front wings. We predicted that male hind wing shape evolves faster than front wing shape, due to sexual selection. Females do not engage in sexual displays, so we predicted that females do not show differences in divergence between front- and hind wing shape. We analysed the nonallometric component of wing shape of five European Calopteryx taxa using geometric morphometrics. We found a higher evolutionary divergence of hind wing shape in both sexes. Indeed, we found no significant differences in rate of evolution between the sexes, despite clear sexspecific differences in wing shape. We suggest that evolution of hind wing shape in males is accelerated by sexual selection on pre-copulatory displays and that this acceleration is reflected in females due to genetic correlations that somehow link the rates of wing shape evolution in the two sexes, but not the wing shapes themselves.

  • 1315. Outomuro, David
    et al.
    Bokma, Folmer
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Johansson, Frank
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hind Wing Shape Evolves Faster than Front Wing Shape in Calopteryx Damselflies2012Inngår i: Evolutionary biology, ISSN 0071-3260, E-ISSN 1934-2845, Vol. 39, nr 1, s. 116-125Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wing shape has been shown in a variety of species to be influenced by natural and sexual selection. In damselflies, front- and hind wings can beat independently, and functional differentiation may occur. Males of Calopteryx damselflies show species-specific nuptial flights that differ in colour signalling with the hind wings. Therefore, hind wing shape and colour may evolve in concert to improve colour display, independent of the front wings. We predicted that male hind wing shape evolves faster than front wing shape, due to sexual selection. Females do not engage in sexual displays, so we predicted that females do not show differences in divergence between front- and hind wing shape. We analysed the non-allometric component of wing shape of five European Calopteryx taxa using geometric morphometrics. We found a higher evolutionary divergence of hind wing shape in both sexes. Indeed, we found no significant differences in rate of evolution between the sexes, despite clear sex-specific differences in wing shape. We suggest that evolution of hind wing shape in males is accelerated by sexual selection on pre-copulatory displays and that this acceleration is reflected in females due to genetic correlations that somehow link the rates of wing shape evolution in the two sexes, but not the wing shapes themselves.

  • 1316.
    Outomuro, David
    et al.
    Biología de Organismos y Sistemas, University of Oviedo.
    Johansson, Frank
    Department of Ecology and Environmental Science, Umeå University.
    The effects of latitude, body size, and sexual selection on wing shape in a damselfly2011Inngår i: Biological Journal of the Linnean Society, ISSN 0024-4066, E-ISSN 1095-8312, Vol. 102, nr 2, s. 263-274Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Under natural selection, wing shape is expected to evolve to optimize flight performance. However, other selective factors besides flight performance may influence wing shape. One such factor could be sexual selection in wing sexual ornaments, which may lead to alternative variations in wing shape that are not necessarily related to flight performance. In the present study, we investigated wing shape variations in a calopterygid damselfly along a latitudinal gradient using geometric morphometrics. Both sexes show wing pigmentation, which is a known signal trait at intra- and interspecific levels. Wing shape differed between sexes and, within the same sex, the shape of the hind wing differed from the front wing. Latitude and body size explained a high percentage of the variation in wing shape for female front and hind wings, and male front wings. In male hind wings, wing pigmentation explained a high amount of the variation in wing shape. On the other hand, the variation in shape explained by pigmentation was very low in females. We suggest that the conservative morphology of front wings is maintained by natural selection operating on flight performance, whereas the sex-specific differences in hind wings most likely could be explained by sexual selection. The observed sexual dimorphism in wing shape is likely a result of different sex-specific behaviours. (C) 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 102, 263-274.

  • 1317.
    Outomuro, David
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi. Univ Cincinnati, Dept Biol Sci, Cincinnati, OH 45221 USA.
    Johansson, Frank
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Wing morphology and migration status, but not body size, habitat or Rapoport's rule predict range size in North-American dragonflies (Odonata: Libellulidae)2019Inngår i: Ecography, ISSN 0906-7590, E-ISSN 1600-0587, Vol. 42, nr 2, s. 309-320Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Understanding why species range sizes vary is important for predicting the impact of environmental change on biodiversity. Here we use a multi-variable approach in a phylogenetic comparative context to understand how four morphological, two ecological, and two eco-geographical variables are associated with range size, latitudinal range and longitudinal range in 81 species of North-American libellulid dragonflies. Our results show that: 1) migratory species and species with a more expanded basal hindwing lobe have a larger range size; 2) opposite to Rapoport's rule, latitudinal range is negatively correlated with mid-range latitude; 3) longitudinal range is predicted by wing morphology and migration; 4) body size and larval habitat are not correlated with range size, latitudinal range or longitudinal range. These results suggest that dispersal-related traits, such as wing shape and migratory status, are important factors in predicting the range size of libellulid dragonflies. In addition, the reverse Rapoport's rule suggests that more northern-centred species might be more specialized than more southern-centred species. We suggest that the variables predicting range size are likely imposed by taxon-specific morphological, ecological, physiological and behavioural traits. Taxon-specific knowledge is thus necessary to understand the dynamics of range sizes and is important to implement successful restoration and conservation plans of threatened species.

  • 1318.
    Outomuro, David
    et al.
    Biología de Organismos y Sistemas, University of Oviedo.
    Ocharan, Francisco J.
    Biología de Organismos y Sistemas, University of Oviedo.
    Wing pigmentation in Calopteryx damselflies: a role in thermoregulation?2011Inngår i: Biological Journal of the Linnean Society, ISSN 0024-4066, E-ISSN 1095-8312, Vol. 103, nr 1, s. 36-44Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Body melanization may show adaptive variation related to thermoregulation ability, and it is to be expected that the degree of melanization will change among populations or closely related species across environmental gradients of solar radiation and/or environmental temperature. Some melanized secondary sexual traits may also play a role in sexual selection, leading to interpopulation variation, which would not be predicted by thermoregulation pressures alone. We studied the relationships between the interpopulation variation in wing pigmentation level (i.e. melanized secondary sexual trait) of two closely related species of Calopteryx damselfly, and both solar radiation and maximum environmental temperature estimates. Wing pigmentation differs between these species, is gender specific and is used in species' discrimination. Only Calopteryx virgo meridionalis males showed a significant negative partial correlation between wing pigmentation degree and temperature. However, C. virgo meridionalis females showed a positive significant partial correlation between wing pigmentation degree and solar radiation. Wing pigmentation in Calopteryx xanthostoma males was not related to solar radiation or temperature. Thus, thermoregulation pressures poorly explained the observed variations in wing pigmentation between populations, although they might have an adaptive significance at the species' level. As wing pigmentation showed important latitudinal variation, several other selection pressures which might act on melanized traits are briefly discussed. (C) 2011 The Linnean Society of London, Biological Journal of the Linnean Society, 2011, 103, 36-44.

  • 1319.
    Outomuro, David
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Söderquist, Linus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Johansson, Frank
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Ödeen, Anders
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi.
    Nordström, Karin
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Fysiologi. Flinders Univ S Australia, Anat & Histol Ctr Neurosci, GPO Box 2100, Adelaide, SA 5001, Australia..
    The price of looking sexy: visual ecology of a three-level predator–prey system2017Inngår i: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 31, nr 3, s. 707-718Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Colour signals and colour vision play a pivotal role in intraspecific communication and predator-prey interactions. However, the costs of expressing conspicuous sexual signals at multiple trophic levels have been largely overlooked. Sexual signals can also experience character displacement in sympatric populations of closely related species, leading to potential changes in conspicuousness. We here investigate a bird-damselfly-fruit fly predator-prey system, where two closely related damselfly species have conspicuous, sexually selected wing coloration. The damselflies can occur in sympatry and allopatry, and reproductive character displacement in the coloration size has been previously reported. We quantify the damselfly wing reflectance from replicated sympatric and allopatric populations, and use receptor noise models to investigate the visual discriminability of the wing coloration for the bird, damselfly and fly vision systems, against natural backgrounds. We perform electroretinograms to study damselfly eye sensitivity. We also estimate damselfly predation risk in natural populations. We find that the chromatic component of wing coloration makes males highly discriminable to the predator, but not to the prey. However, female wing coloration is predominantly cryptic for the predator and prey, and interestingly, also for male damselflies. A female being cryptic to conspecifics likely reduces male harassment. The estimates of predation risk partially support the discriminability results. We also show that there is no difference in colour vision sensitivity between the two damselfly species and sexes, and no difference in wing coloration or its discriminability between sympatric and allopatric populations. Our results suggest that sexually selected traits can be antagonistically selected by predators and prey and that this antagonistic selection can be sex-dependent: males are paying a large cost in terms of conspicuousness, while females remain mostly cryptic. Our study thus emphasizes the need for investigating visual communication at multitrophic levels since the degree of colour discriminability can differ between predators, prey and the focal species.

  • 1320.
    Outomuro, David
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Söderquist, Linus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Nilsson-Örtman, Viktor
    Department of Ecology and Evolutionary Biology, University of Toronto, ON M5S 3B2, Canada;Evolutionary Ecology Unit, Biology Department, Lund University, SE223-62 Lund, Sweden.
    Cortázar-Chinarro, María
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Lundgren, Cecilia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Johansson, Frank
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Antagonistic natural and sexual selection on wing shape in a scrambling damselfly2016Inngår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 70, nr 7, s. 1582-1595Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Wings are a key trait underlying the evolutionary success of birds, bats, and insects. For over a century, researchers have studiedthe form and function of wings to understand the determinants of flight performance. However, to understand the evolutionof flight, we must comprehend not only how morphology affects performance, but also how morphology and performanceaffect fitness. Natural and sexual selection can either reinforce or oppose each other, but their role in flight evolution remainspoorly understood. Here, we show that wing shape is under antagonistic selection with regard to sexual and natural selectionin a scrambling damselfly. In a field setting, natural selection (survival) favored individuals with long and slender forewings andshort and broad hindwings. In contrast, sexual selection (mating success) favored individuals with short and broad forewings andnarrow-based hindwings. Both types of selection favored individuals of intermediate size. These results suggest that individualsface a trade-off between flight energetics and maneuverability and demonstrate how natural and sexual selection can operate insimilar directions for some wing traits, that is, wing size, but antagonistically for others, that is, wing shape. Furthermore, theyhighlight the need to study flight evolution within the context of species’ mating systems and mating behaviors.

  • 1321.
    Outomuro, David
    et al.
    Biología de Organismos y Sistemas, University of Oviedo.
    Torralba-Burrial, Antonio
    Biología de Organismos y Sistemas, University of Oviedo.
    Ocharan, Francisco J.
    Biología de Organismos y Sistemas, University of Oviedo.
    Distribution of the Iberian Calopteryx damselflies and its relation with bioclimatic belts: Evolutionary and biogeographic implications2010Inngår i: Journal of Insect Science, ISSN 1536-2442, E-ISSN 1536-2442, Vol. 10Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Using bioclimatic belts as habitat and distribution predictors, the present study examines the implications of the potential distributions of the three Iberian damselflies, Calopteryx Leach (Odonata: Calopterygidae), with the aim of investigating the possible consequences in specific interactions among the species from a sexual selection perspective and of discussing biogeographical patterns. To obtain the known distributions, the literature on this genus was reviewed, relating the resulting distributions to bioclimatic belts. Specific patterns related to bioclimatic belts were clearly observed in the Mediterranean region. The potential distribution maps and relative frequencies might involve latitudinal differences in relative abundances, C. virgo meridionalis Selys being the most abundant species in the Eurosiberian region, C. xanthostoma (Charpentier) in the northern half of the Mediterranean region and C. haemorrhoidalis (Vander Linden) in the rest of this region. These differences might explain some previously described latitudinal differences in secondary sexual traits in the three species. Changes in relative abundances may modulate interactions among these species in terms of sexual selection and may produce sexual character displacement in this genus. C. virgo meridionalis distribution and ecological requirements explain its paleobiogeography as a species which took refuge in Iberia during the Wurm glaciation. Finally, possible consequences in species distributions and interactions are discussed within a global climate change context.

  • 1322.
    Outomuro, David
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Zooekologi. Univ Los Andes, Dept Ciencias Biol, Lab Zool & Ecol Acuat, Bogota, Colombia.
    Ángel-Giraldo, Pedro
    Univ Los Andes, Dept Ciencias Biol, Lab Zool & Ecol Acuat, Bogota, Colombia.
    Corral-Lopez, Alberto
    Stockholm Univ, Dept Ethol Zool, Svante Arrhenius Vag 18B, S-10691 Stockholm, Sweden.
    Realpe, Emilio
    Univ Los Andes, Dept Ciencias Biol, Lab Zool & Ecol Acuat, Bogota, Colombia.
    Multitrait aposematic signal in Batesian mimicry2016Inngår i: Evolution, ISSN 0014-3820, E-ISSN 1558-5646, Vol. 70, nr 7, s. 1596-1608Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Batesian mimics can parasitize Müllerian mimicry rings mimicking the warning color signal. The evolutionary success of Batesian mimics can increase adding complexity to the signal by behavioral and locomotor mimicry. We investigated three fundamental morphological and locomotor traits in a Neotropical mimicry ring based on Ithomiini butterflies and parasitized by Polythoridae damselflies: wing color, wing shape, and flight style. The study species have wings with a subapical white patch, considered the aposematic signal, and a more apical black patch. The main predators are VS-birds, visually more sensitive to violet than to ultraviolet wavelengths (UVS-birds). The white patches, compared to the black patches, were closer in the bird color space, with higher overlap for VS-birds than for UVS-birds. Using a discriminability index for bird vision, the white patches were more similar between the mimics and the model than the black patches. The wing shape of the mimics was closer to the model in the morphospace, compared to other outgroup damselflies. The wing-beat frequency was similar among mimics and the model, and different from another outgroup damselfly. Multitrait aposematic signals involving morphology and locomotion may favor the evolution of mimicry rings and the success of Batesian mimics by improving signal effectiveness toward predators.

  • 1323.
    Owers, Katharine A.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi. Yale Univ, Sch Publ Hlth, Dept Epidemiol Microbial Dis, New Haven, CT USA..
    Sjödin, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Schlebusch, Carina M.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Skoglund, Pontus
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi.
    Soodyall, Himla
    Univ Witwatersrand, Fac Hlth Sci, Sch Pathol, Div Human Genet, Johannesburg, South Africa.;Natl Hlth Lab Serv, Johannesburg, South Africa..
    Jakobsson, Mattias
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionsbiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Adaptation to infectious disease exposure in indigenous Southern African populations2017Inngår i: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 284, nr 1852, artikkel-id 20170226Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Genetic analyses can provide information about human evolutionary history that cannot always be gleaned from other sources. We evaluated evidence of selective pressure due to introduced infectious diseases in the genomes of two indigenous southern African San groups-the double dagger Khomani who had abundant contact with other people migrating into the region and the more isolated Ju vertical bar'hoansi. We used a dual approach to test for increased selection on immune genes compared with the rest of the genome in these groups. First, we calculated summary values of statistics that measure genomic signatures of adaptation to contrast selection signatures in immune genes and all genes. Second, we located regions of the genome with extreme values of three selection statistics and examined these regions for enrichment of immune genes. We found stronger and more abundant signals of selection in immune genes in the double dagger Khomani than in the Ju vertical bar'hoansi. We confirm this finding within each population to avoid effects of different demographic histories of the two populations. We identified eight immune genes that have potentially been targets of strong selection in the double dagger Khomani, whereas in the Juj'hoansi, no immune genes were found in the genomic regions with the strongest signals of selection. We suggest that the more abundant signatures of selection at immune genes in the double dagger Khomani could be explained by their more frequent contact with immigrant groups, which likely led to increased exposure and adaptation to introduced infectious diseases.

  • 1324.
    Owusu, Christian Kwasi
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för biologisk grundutbildning.
    Comparative analysis of endoparasitic helminths in Lake Tanganyikan cichlids: host body mass and social interaction as determinants of parasite load2013Independent thesis Advanced level (degree of Master (Two Years)), 80 poäng / 120 hpOppgave
    Abstract [en]

    Parasites are an important component of every ecosystem, and their interactions with hosts can directly impact the fitness of the host organisms. Despite their significance, it is still largely unknown which host traits predispose a species to increased risk of parasite attack. In the present study, I investigated host and ecological correlates of parasite load in Lake Tanganyikan cichlids using phylogenetic comparative analyses. Specifically, I tested the effect of body size, brain mass, gut length, depth, trophic level, habitat complexity and mating system on parasite prevalence and diversity.  I found that the variation in both average infracommunity richness and parasite prevalence were partly explained by host body mass and habitat complexity. Total parasite diversity, on the other hand, was significantly related to mating behaviour as well as habitat complexity. The comparative analysis presented here is, to the best of my knowledge, the first to investigate determinants of parasite load in Lake Tanganyikan cichlids. As such, my results support several major hypotheses concerning the factors that underlie parasite prevalence and diversity and have broad implications for our understanding of parasite-host interactions.

     

  • 1325. Owusu, Sandra A.
    et al.
    Sullivan, Alexis R.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Michigan Technol Univ, Houghton, USA.
    Weber, Jaime A.
    Hipp, Andrew L.
    Gailing, Oliver
    Taxonomic Relationships and Gene Flow in Four North American Quercus Species (Quercus section Lobatae)2015Inngår i: Systematic Botany, ISSN 0363-6445, E-ISSN 1548-2324, Vol. 40, nr 2, s. 510-521Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Taxonomic relationships between North American red oak species (Quercus section Lobatae) are not well resolved using genetic and morphological markers. Phenotypic plasticity, recent species divergence, and hybridization may all contribute to the unclear species boundaries in red oaks. We applied twenty-eight genomic and gene-basedmicrosatellites, including outlier loci with potential roles in reproductive isolation and adaptive divergence between species, to natural populations of four monophyletic interfertile oak species: Quercus ellipsoidalis, Q. coccinea, Q. rubra, and Q. velutina. To better resolve the taxonomic relationships in this difficult clade, we assigned individual samples to species, identified hybrids and introgressive forms, and reconstructed phylogenetic relationships among the four species after exclusion of genetically intermediate individuals. Genetic assignment analyses identified four distinct species clusters, with Q. rubra most differentiated from the three other species. However, especially between Q. ellipsoidalis and Q. velutina, a comparatively large number of misclassified individuals (7.14%), hybrids (7.14%), and introgressive forms (18.83%) were detected. After the exclusion of genetically intermediate individuals, Q. ellipsoidalis grouped as sister species to the largely parapatric Q. coccinea with high bootstrap support (91%). Genetically intermediate forms in a mixed species stand were located proximate to both potential parental species, which supports recent hybridization of Q. velutina with both Q. ellipsoidalis and Q. rubra. Analyses of genome-wide patterns of interspecific differentiation can provide a better understanding of speciation processes and taxonomic relationships in this taxonomically difficult group of red oak species.

  • 1326. Palkopoulou, Eleftheria
    et al.
    Baca, Mateusz
    Abramson, Natalia I.
    Sablin, Mikhail
    Socha, Pawel
    Nadachowski, Adam
    Prost, Stefan
    Germonpre, Mietje
    Kosintsev, Pavel
    Smirnov, Nickolay G.
    Vartanyan, Sergey
    Ponomarev, Dmitry
    Nystroem, Johanna
    Nikolskiy, Pavel
    Jass, Christopher N.
    Litvinov, Yuriy N.
    Kalthoff, Daniela C.
    Grigoriev, Semyon
    Fadeeva, Tatyana
    Douka, Aikaterini
    Higham, Thomas F. G.
    Ersmark, Erik
    Pitulko, Vladimir
    Pavlova, Elena
    Stewart, John R.
    Weglenski, Piotr
    Stankovic, Anna
    Dalen, Love
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Synchronous genetic turnovers across Western Eurasia in Late Pleistocene collared lemmings2016Inngår i: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 22, nr 5, s. 1710-1721Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Recent palaeogenetic studies indicate a highly dynamic history in collared lemmings (Dicrostonyx spp.), with several demographical changes linked to climatic fluctuations that took place during the last glaciation. At the western range margin of D.torquatus, these changes were characterized by a series of local extinctions and recolonizations. However, it is unclear whether this pattern represents a local phenomenon, possibly driven by ecological edge effects, or a global phenomenon that took place across large geographical scales. To address this, we explored the palaeogenetic history of the collared lemming using a next-generation sequencing approach for pooled mitochondrial DNA amplicons. Sequences were obtained from over 300 fossil remains sampled across Eurasia and two sites in North America. We identified five mitochondrial lineages of D.torquatus that succeeded each other through time across Europe and western Russia, indicating a history of repeated population extinctions and recolonizations, most likely from eastern Russia, during the last 50000years. The observation of repeated extinctions across such a vast geographical range indicates large-scale changes in the steppe-tundra environment in western Eurasia during the last glaciation. AllHolocene samples, from across the species' entire range, belonged to only one of the five mitochondrial lineages. Thus, extant D.torquatus populations only harbour a small fraction of the total genetic diversity that existed across different stages of the Late Pleistocene. In North American samples, haplotypes belonging to both D.groenlandicus and D.richardsoni were recovered from a Late Pleistocene site in south-western Canada. This suggests that D.groenlandicus had a more southern and D.richardsoni a more northern glacial distribution than previously thought. This study provides significant insights into the population dynamics of a small mammal at a large geographical scale and reveals a rather complex demographical history, which could have had bottom-up effects in the Late Pleistocene steppe-tundra ecosystem.

  • 1327.
    Palkopoulou, Eleftheria
    et al.
    Harvard Med Sch, Dept Genet, Boston, MA 02115 USA.;Broad Inst MIT & Harvard, Cambridge, MA 02142 USA..
    Lipson, Mark
    Harvard Med Sch, Dept Genet, Boston, MA 02115 USA..
    Mallick, Swapan
    Harvard Med Sch, Dept Genet, Boston, MA 02115 USA.;Broad Inst MIT & Harvard, Cambridge, MA 02142 USA..
    Nielsen, Svend
    Aarhus Univ, Bioinformat Res Ctr, DK-8000 Aarhus, Denmark..
    Rohland, Nadin
    Harvard Med Sch, Dept Genet, Boston, MA 02115 USA..
    Baleka, Sina
    Univ Potsdam, Unit Gen Zool Evolutionary Adapt Genom, Inst Biochem & Biol, Fac Math & Life Sci, D-14476 Potsdam, Germany..
    Karpinski, Emil
    McMaster Univ, McMaster Ancient DNA Ctr, Dept Anthropol, Hamilton, ON L8S 4L9, Canada.;McMaster Univ, Dept Biol, Hamilton, ON L8S 4K1, Canada.;McMaster Univ, Dept Biochem, Hamilton, ON L8S 4L8, Canada.;McMaster Univ, Michael G DeGroote Inst Infect Dis Res, Hamilton, ON L8S 4L8, Canada..
    Ivancevici, Atma M.
    Univ Adelaide, Sch Biol Sci, Dept Genet & Evolut, Adelaide, SA 5005, Australia..
    To, Thu-Hien
    Kortschak, Daniel
    Univ Adelaide, Sch Biol Sci, Dept Genet & Evolut, Adelaide, SA 5005, Australia..
    Raison, Joy M.
    Univ Adelaide, Sch Biol Sci, Dept Genet & Evolut, Adelaide, SA 5005, Australia..
    Qu, Zhipeng
    Univ Adelaide, Sch Biol Sci, Dept Genet & Evolut, Adelaide, SA 5005, Australia..
    Chin, Tat-Jun
    Univ Adelaide, Sch Comp Sci, Adelaide, SA 5005, Australia..
    Alt, Kurt W.
    Danube Private Univ, Ctr Nat & Cultural Human Hist, A-3500 Krems, Austria.;Univ Basel, Univ Basel Hosp, Dept Biomed Engn, CH-4123 Basel, Switzerland.;Univ Basel, Integrat Prehist & Archaeol Sci, CH-4051 Basel, Switzerland..
    Claesson, Stefan
    Inst Maritime Hist, Tall Timbers, MD 20690 USA..
    Dalen, Love
    Swedish Museum Nat Hist, Dept Bioinformat & Genet, SE-10405 Stockholm, Sweden..
    MacPhee, Ross D. E.
    Amer Museum Nat Hist, Div Vertebrate Zool Mammal, New York, NY 10024 USA..
    Meller, Harald
    State Off Heritage Management & Archaeol, D-06114 Halle, Saale, Germany..
    Rocar, Alfred L.
    Univ Illinois, Dept Anim Sci, Urbana, IL 61801 USA.;Univ Illinois, Inst Genom Biol, Urbana, IL 61801 USA..
    Ryder, Oliver A.
    San Diego Zoo, Inst Conservat Res, Escondido, CA 92027 USA..
    Heiman, David
    Broad Inst MIT & Harvard, Cambridge, MA 02142 USA..
    Young, Sarah
    Broad Inst MIT & Harvard, Cambridge, MA 02142 USA..
    Breen, Matthew
    North Carolina State Univ, Coll Vet Med, Dept Mol Biomed Sci, Raleigh, NC 27607 USA..
    Williams, Christina
    North Carolina State Univ, Coll Vet Med, Dept Mol Biomed Sci, Raleigh, NC 27607 USA..
    Aken, Bronwen L.
    European Bioinformat Inst, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Sanger Inst, Cambridge CB10 1SD, England..
    Ruffier, Magali
    European Bioinformat Inst, European Mol Biol Lab, Cambridge CB10 1SD, England.;Wellcome Sanger Inst, Cambridge CB10 1SD, England..
    Karlsson, Elinor
    Broad Inst MIT & Harvard, Cambridge, MA 02142 USA.;Univ Massachusetts, Sch Med, Program Bioinformat & Integrat Biol, Worcester, MA 01655 USA..
    Johnson, Jeremy
    Broad Inst MIT & Harvard, Cambridge, MA 02142 USA..
    Di Palma, Federica
    Earlham Inst, Norwich NR4 7UZ, Norfolk, England..
    Alfoldi, Jessica
    Broad Inst MIT & Harvard, Cambridge, MA 02142 USA..
    Adelsoni, David L.
    Univ Adelaide, Sch Biol Sci, Dept Genet & Evolut, Adelaide, SA 5005, Australia..
    Mailund, Thomas
    Aarhus Univ, Bioinformat Res Ctr, DK-8000 Aarhus, Denmark..
    Munch, Kasper
    Aarhus Univ, Bioinformat Res Ctr, DK-8000 Aarhus, Denmark..
    Lindblad-Toh, Kerstin
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för medicinsk biokemi och mikrobiologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab. Broad Inst MIT & Harvard, Cambridge, MA 02142 USA.
    Hofreiter, Michael
    Univ Potsdam, Unit Gen Zool Evolutionary Adapt Genom, Inst Biochem & Biol, Fac Math & Life Sci, D-14476 Potsdam, Germany..
    Poinar, Hendrik
    McMaster Univ, McMaster Ancient DNA Ctr, Dept Anthropol, Hamilton, ON L8S 4L9, Canada.;McMaster Univ, Dept Biol, Hamilton, ON L8S 4K1, Canada.;McMaster Univ, Dept Biochem, Hamilton, ON L8S 4L8, Canada.;McMaster Univ, Michael G DeGroote Inst Infect Dis Res, Hamilton, ON L8S 4L8, Canada..
    Reich, David
    Harvard Med Sch, Dept Genet, Boston, MA 02115 USA.;Broad Inst MIT & Harvard, Cambridge, MA 02142 USA.;Harvard Med Sch, Howard Hughes Med Inst, Boston, MA 02115 USA..
    A comprehensive genomic history of extinct and living elephants2018Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 115, nr 11, s. E2566-E2574Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Elephantids are the world's most iconic megafaunal family, yet there is no comprehensive genomic assessment of their relationships. We report a total of 14 genomes, including 2 from the American mastodon, which is an extinct elephantid relative, and 12 spanning all three extant and three extinct elephantid species including an similar to 120,000-y-old straight-tusked elephant, a Columbian mammoth, and woolly mammoths. Earlier genetic studies modeled elephantid evolution via simple bifurcating trees, but here we show that interspecies hybridization has been a recurrent feature of elephantid evolution. We found that the genetic makeup of the straight-tusked elephant, previously placed as a sister group to African forest elephants based on lower coverage data, in fact comprises three major components. Most of the straight-tusked elephant's ancestry derives from a lineage related to the ancestor of African elephants while its remaining ancestry consists of a large contribution from a lineage related to forest elephants and another related to mammoths. Columbian and woolly mammoths also showed evidence of interbreeding, likely following a latitudinal cline across North America. While hybridization events have shaped elephantid history in profound ways, isolation also appears to have played an important role. Our data reveal nearly complete isolation between the ancestors of the African forest and savanna elephants for similar to 500,000 y, providing compelling justification for the conservation of forest and savanna elephants as separate species.

  • 1328.
    Pan, Qiaowei
    et al.
    INRA, Fish Physiol & Genom Lab, F-35042 Rennes, France..
    Anderson, Jennifer
    INRA, Fish Physiol & Genom Lab, F-35042 Rennes, France..
    Bertho, Sylvain
    INRA, Fish Physiol & Genom Lab, F-35042 Rennes, France.;Univ Wurzburg, Physiol Chem, Bioctr, D-97074 Wurzburg, Germany..
    Herpin, Amaury
    INRA, Fish Physiol & Genom Lab, F-35042 Rennes, France..
    Wilson, Catherine
    Univ Oregon, Inst Neurosci, Eugene, OR 97403 USA..
    Postlethwait, John H.
    Univ Oregon, Inst Neurosci, Eugene, OR 97403 USA..
    Schartl, Manfred
    Univ Wurzburg, Physiol Chem, Bioctr, D-97074 Wurzburg, Germany.;Univ Hosp, Comprehens Canc Ctr Mainfranken, D-97080 Wurzburg, Germany.;Texas A&M Univ, Texas Inst Adv Study, College Stn, TX 77843 USA.;Texas A&M Univ, Dept Biol, College Stn, TX 77843 USA..
    Guiguen, Yann
    INRA, Fish Physiol & Genom Lab, F-35042 Rennes, France..
    Vertebrate sex-determining genes play musical chairs2016Inngår i: Comptes rendus. Biologies, ISSN 1631-0691, E-ISSN 1768-3238, Vol. 339, nr 7-8, s. 258-262Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sexual reproduction is one of the most highly conserved processes in evolution. However, the genetic and cellular mechanisms making the decision of whether the undifferentiated gonad of animal embryos develops either towards male or female are manifold and quite diverse. In vertebrates, sex-determining mechanisms range from environmental to simple or complex genetic mechanisms and different mechanisms have evolved repeatedly and independently. In species with simple genetic sex-determination, master sex-determining genes lying on sex chromosomes drive the gonadal differentiation process by switching on a developmental program, which ultimately leads to testicular or ovarian differentiation. So far, very few sex-determining genes have been identified in vertebrates and apart from mammals and birds, these genes are apparently not conserved over a larger number of related orders, families, genera, or even species. To fill this knowledge gap and to better explore genetic sex-determination, we propose a strategy (RAD-Sex) that makes use of next-generation sequencing technology to identify genetic markers that define sex-specific segments of the male or female genome.

  • 1329.
    Panara, Virginia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för biologisk grundutbildning.
    DMRT genes expression in the embryos of Panarthropoda2018Independent thesis Advanced level (degree of Master (Two Years)), 30 poäng / 45 hpOppgave
  • 1330.
    Parachnowitsch, Amy
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    New Synthesis: The Evolutionary Ecology of Floral Volatiles2014Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 40, nr 8, s. 859-859Artikkel i tidsskrift (Annet vitenskapelig)
  • 1331.
    Parachnowitsch, Amy
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Burdon, Rosalie
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Ragusso, Robert
    Cornell.
    Kessler, Andre
    Cornell.
    Natural selection on floral volatile production in Penstemon digitalis: Highlighting the role of linalool2013Inngår i: Plant Signalling & Behavior, ISSN 1559-2316, E-ISSN 1559-2324, Vol. 8, nr 1, s. e22704-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Natural selection is thought to have shaped the evolution of floral scent; however, unlike other floral characters, we have a rudimentary knowledge of how phenotypic selection acts on scent. We found that floral scent was under stronger selection than corolla traits such as flower size and flower color in weakly scented Penstemon digitalis. Our results suggest that to understand evolution in floral phenotypes, including scent in floral selection, studies are crucial. For P. digitalis, linalool was the direct target of selection in the scent bouquet. Therefore, we determined the enantiomeric configuration of linalool because interacting insects may perceive the enantiomers differentially. We found that P. digitalis produces only (S)-(+)-linalool and, more interestingly, it is also taken up into the nectar. Because the nectar is scented and flavored with (S)-(+)-linalool, it may be an important cue for pollinators visiting P. digitalis flowers.

  • 1332.
    Parachnowitsch, Amy L.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Interpreting local adaptation studies2013Inngår i: Ideas in Ecology and Evolution, ISSN 1918-3178, Vol. 6, nr 1, s. 37-39Artikkel i tidsskrift (Fagfellevurdert)
  • 1333.
    Parachnowitsch, Amy L.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Manson, JS
    Sletvold, Nina
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Evolutionary ecology of nectar2018Inngår i: s. 1-15, artikkel-id mcy132Artikkel i tidsskrift (Fagfellevurdert)
  • 1334.
    Parducci, Laura
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Bennett, K. D.
    Univ St Andrews, Geog & Sustainable Dev, St Andrews KY16 9AL, Fife, Scotland.;Queens Univ Belfast, Marine Lab, Portaferry BT22 1LS, North Ireland..
    The real significance of ancient DNA2017Inngår i: American Journal of Botany, ISSN 0002-9122, E-ISSN 1537-2197, Vol. 104, nr 6, s. 800-802Artikkel i tidsskrift (Annet vitenskapelig)
  • 1335.
    Parducci, Laura
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionär funktionsgenomik.
    Bennett, K.D.
    Ancient DNA studies in plant populations2010Inngår i: Molecular markers, PCR, bioinformatics and ancient DNA-technology, troubleshooting and applications / [ed] Dorado, G., Cordoba: Cordoba University , 2010Kapittel i bok, del av antologi (Fagfellevurdert)
  • 1336.
    Parducci, Laura
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Bennett, Keith D.
    Univ St Andrews, Dept Geog & Sustainable Dev, Sch Geog & Geosci, St Andrews KY16 9AL, Fife, Scotland.;Queens Univ Belfast, Marine Lab, Portaferry BT22 1LS, North Ireland..
    Ficetola, Gentile Francesco
    Univ Grenoble Alpes, CNRS, Lab Ecol Alpine LECA, F-38000 Grenoble, France.;Univ Milan, Dept Biosci, I-20133 Milan, Italy..
    Alsos, Inger Greve
    UiT Arctic Univ Norway, Tromso Museum, NO-9037 Tromso, Norway..
    Suyama, Yoshihisa
    Tohoku Univ, Grad Sch Agr Sci, Field Sci Ctr, 232-3 Yomogida, Osaki, Miyagi 9896711, Japan..
    Wood, Jamie R.
    Landcare Res, Longterm Ecol Lab, POB 69040, Lincoln Canterbury 7640, New Zealand..
    Pedersen, Mikkel Winther
    Univ Copenhagen, Ctr GeoGenet, Nat Hist Museum Denmark, DK-1350 Copenhagen, Denmark..
    Ancient plant DNA in lake sediments2017Inngår i: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 214, nr 3, s. 924-942Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    Recent advances in sequencing technologies now permit the analyses of plant DNA from fossil samples (ancient plant DNA, plant aDNA), and thus enable the molecular reconstruction of palaeofloras. Hitherto, ancient frozen soils have proved excellent in preserving DNA molecules, and have thus been the most commonly used source of plant aDNA. However, DNA from soil mainly represents taxa growing a few metres from the sampling point. Lakes have larger catchment areas and recent studies have suggested that plant a DNA from lake sediments is a more powerful tool for palaeofloristic reconstruction. Furthermore, lakes can be found globally in nearly all environments, and are therefore not limited to perennially frozen areas. Here, we review the latest approaches and methods for the study of plant aDNA from lake sediments and discuss the progress made up to the present. We argue that a DNA analyses add new and additional perspectives for the study of ancient plant populations and, in time, will provide higher taxonomic resolution and more precise estimation of abundance. Despite this, key questions and challenges remain for such plant aDNA studies. Finally, we provide guidelines on technical issues, including lake selection, and we suggest directions for future research on plant aDNA studies in lake sediments.

  • 1337.
    Parducci, Laura
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Evolutionär funktionsgenomik.
    Suyama, Y.
    Single-pollen genotyping of Holocene lake sediments2010Inngår i: Single-pollen genotyping / [ed] Isagi, Y. & Suyama, Y., Springer-Verlag Tokyo Inc., 2010Kapittel i bok, del av antologi (Fagfellevurdert)
  • 1338.
    Park, Sungkyu
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi, Avdelningen för farmakognosi.
    Cyclotides evolve: Studies on their natural distribution, structural diversity, and activity2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    The cyclotides are a family of naturally occurring peptides characterized by cyclic cystine knot (CCK) structural motif, which comprises a cyclic head-to-tail backbone featuring six conserved cysteine residues that form three disulfide bonds. This unique structural motif makes cyclotides exceptionally resistant to chemical, thermal and enzymatic degradation. They also exhibit a wide range of biological activities including insecticidal, cytotoxic, anti-HIV and antimicrobial effects.

    The cyclotides found in plants exhibit considerable sequence and structural diversity, which can be linked to their evolutionary history and that of their host plants. To clarify the evolutionary link between sequence diversity and the distribution of individual cyclotides across the genus Viola, selected known cyclotides were classified using signature sequences within their precursor proteins. By mapping the classified sequences onto the phylogenetic system of Viola, we traced the flow of cyclotide genes over evolutionary history and were able to estimate the prevalence of cyclotides in this genus. In addition, the structural diversity of the cyclotides was related to specific features of the sequences of their precursor proteins, their evolutionary selection and expression levels.

    A number of studies have suggested that the biological activities of the cyclotides are due to their ability to interact with and disrupt biological membranes. To better explain this behavior, quantitative structure-activity relationship (QSAR) models were developed to link the cyclotides’ biological activities to the membrane-interactive physicochemical properties of their molecular surfaces. Both scalar quantities (such as molecular surface areas) and moments (such as the distributions of specific properties over the molecular surface) were systematically taken into account in the development of these models. This approach allows the physicochemical properties of cyclotides to be geometrically interpreted, facilitating the development of guidelines for drug design using cyclotide scaffolds.

    Finally, an optimized microwave-assisted Fmoc-SPSS procedure for the total synthesis of cyclotides was developed. Microwave irradiation is used to accelerate and improve all the key steps in cyclotide synthesis, including the assembly of the peptide backbone by Fmoc-SPPS, the cleavage of the protected peptide, and the introduction of a thioester at the C-terminal carboxylic acid to obtain the head-to-tail cyclized cyclotide backbone by native chemical ligation. 

  • 1339.
    Park, Sungkyu
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi.
    Yoo, Ki-Oug
    Jacobsson, Erik
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi.
    Ajawantanawong, Pravech
    Backlund, Anders
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi.
    Rosengren, Johan
    Doo, Inseok
    Göransson, Ulf
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Farmaceutiska fakulteten, Institutionen för läkemedelskemi.
    Insights into cyclotide evolution from transcriptomic analyses and studies on their distribution in violetsManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Cyclotides are a family of plant-derived proteins that are characterized by a cyclic backbone and a knotted disulfide topology. Their cyclic cystine knot (CCK) motif makes them exceptionally resistant to thermal, chemical, and enzymatic degradation. Cyclotides exert much of their biological activity via interactions with cell membranes. In this work, we explore cyclotide evolution by sequencing and analyzing the transcriptomes of Viola albida var. takahashii, V. mandshurica, V. orientalis, V. verecunda and V. acuminata, in combination with reported precursor sequences. The distribution of the cyclotide precursors in the genus Viola was analyzed in relation to the infrageneric phylogeny, providing insights into the overall distribution of cyclotides within the genus. The structures and activities of predicted cyclotides are linked to the evolution of their precursors and the associated selective pressures. Furthermore, sequence variations between related precursors were generalized to deduce evolutionary trends, and to shed light on the evolution into novel mature cyclotides with the emergence of new functions. 

  • 1340. Parvinen, Kalle
    et al.
    Brännstrom, Åke
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för matematik och matematisk statistik. Evolution and Ecology Program, International Institute for Applied Systems Analysis, Laxenburg, Austria.
    Evolution of Site-Selection Stabilizes Population Dynamics, Promotes Even Distribution of Individuals, and Occasionally Causes Evolutionary Suicide2016Inngår i: Bulletin of Mathematical Biology, ISSN 0092-8240, E-ISSN 1522-9602, Vol. 78, nr 8, s. 1749-1772Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Species that compete for access to or use of sites, such as parasitic mites attaching to honey bees or apple maggots laying eggs in fruits, can potentially increase their fitness by carefully selecting sites at which they face little or no competition. Here, we systematically investigate the evolution of site-selection strategies among animals competing for discrete sites. By developing and analyzing a mechanistic and population-dynamical model of site selection in which searching individuals encounter sites sequentially and can choose to accept or continue to search based on how many conspecifics are already there, we give a complete characterization of the different site-selection strategies that can evolve. We find that evolution of site-selection stabilizes population dynamics, promotes even distribution of individuals among sites, and occasionally causes evolutionary suicide. We also discuss the broader implications of our findings and propose how they can be reconciled with an earlier study (Nonaka et al. in J Theor Biol 317:96-104, 2013) that reported selection toward ever higher levels of aggregation among sites as a consequence of site-selection.

  • 1341. Patino, Jairo
    et al.
    Bisang, Irene
    Naturhistoriska riksmuseet, Enheten för botanik.
    Hedenäs, Lars
    Naturhistoriska riksmuseet, Enheten för botanik.
    Dirkse, Gerard
    Bjarnason, Agust H.
    Ah-Peng, Claudine
    Vanderpoorten, Alain
    Baker’s law and the island syndromes in bryophytes2013Inngår i: Journal of Ecology, ISSN 0022-0477, E-ISSN 1365-2745, Vol. 101, s. 1245-1255Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    1. The evolution of island syndromes has long served as a model to understand the mechanisms accounting for phenotypic differentiation. Combining literature data with actual observations, we determine whether typical syndromes such as the loss of dispersal power and the bias towards selfcompatibility s law) apply to vagile organisms, using bryophytes as a model.

    2. The life-history traits (LHTs) observed in oceanic island floras were statistically different from those observed on continents, evidencing the evolution of island syndromes. In contrast, LHTs of continental and continental island floras were similar, pointing to differences in migration intensity between continents, continental islands and oceanic islands.

    3. The proportion of bisexual species was significantly higher on oceanic islands than on continents. A significant proportion of species that are unisexual or bisexual on continents shifted towards exclusive bisexuality on oceanic islands, suggesting that Baker’s law applies to bryophytes. The underlying mechanisms, however, probably differ from in situ selection for selfing.

    4. The proportion of species producing specialized asexual diaspores, which are assumed to play a role in short-distance dispersal (SDD), was higher on oceanic islands than on continents. The proportion of species producing spores, which are involved in long-distance dispersal (LDD), exhibited the reverse trend, suggesting a shift in the prevalent reproductive strategy to favour SDD on oceanic islands. Approximately 50% of the species, however, maintained the ability to produce sporophytes on oceanic islands, and the relative frequency of fertile shoots within collections of four model species was even higher on islands than on continents.

    5. Synthesis. Bryophytes exhibit typical island syndromes, indicating that migration rates between oceanic islands and continents are not sufficient to prevent the effects of genetic drift and contradicting the view that the sea does not impede migration in the group. Significant shifts in life-history traits (LHTs) towards increased production of specialized asexual diaspores and decreased sporophyte production on oceanic islands indeed point to a global loss of long-distance dispersal (LDD) ability. The maintenance of traits characteristic for LDD in a large number of species has, however, substantial consequences for our understanding of island plant evolution, and in particular, for our vision of islands as evolutionary dead ends.

  • 1342.
    Pauliny, Angela
    et al.
    Dept of Biological and Environmental Sciences, Univ of Gothenburg.
    Larsson, Kjell
    Högskolan på Gotland, Institutionen för kultur, energi och miljö.
    Blomqvist, Donald
    Dept of Biological and Environmental Sciences, Univ of Gothenburg.
    Telomere dynamics in a long-lived bird, the barnacle goose2012Inngår i: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 12, nr 257Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Theories of ageing predict a trade-off between metabolism, reproduction, and maintenance. Species with low investment in early reproduction are thus expected to be able to evolve more efficient maintenance and repair mechanisms, allowing for a longer potential life span (intrinsic longevity). The erosion of telomeres, the protective caps at the ends of linear chromosomes, plays an important role in cellular and organismal senescence, signalling the onset of age-related disease due to accumulation of unrepaired somatic damage. Using extensive longitudinal data from a long-term study of a natural population of barnacle geese Branta leucopsis, we investigated individual rates of telomere length changes over two years in 34 birds between 0 and 22 years of age, covering almost 80% of the species' lifespan. We show that telomeres in this long-lived bird are very well maintained, as theoretically expected, with an average loss rate of only 5 base pairs per year among adults. We thus found no significant relationship between change in telomere length and age. However, telomeres tended to shorten at a faster pace in juveniles compared to adults. For the first time, we demonstrate a faster telomere attrition rate in females compared to males. We found no correlation between telomere loss rate and adult survival or change in body mass. Our results add further support for a link between longevity and telomere maintenance, and highlight the complexities of telomere dynamics in natural populations.

  • 1343.
    Pauliny, Angela
    et al.
    University of Gothenburg.
    Larsson, Kjell
    Linnéuniversitetet, Fakultetsnämnden för naturvetenskap och teknik, Sjöfartshögskolan, SJÖ. Gotland University.
    Blomqvist, Donald
    University of Gothenburg.
    Telomere dynamics in a long-lived bird, the barnacle goose2012Inngår i: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 12, artikkel-id 257Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Theories of ageing predict a trade-off between metabolism, reproduction, and maintenance. Species with low investment in early reproduction are thus expected to be able to evolve more efficient maintenance and repair mechanisms, allowing for a longer potential life span (intrinsic longevity). The erosion of telomeres, the protective caps at the ends of linear chromosomes, plays an important role in cellular and organismal senescence, signalling the onset of age-related disease due to accumulation of unrepaired somatic damage. Using extensive longitudinal data from a long-term study of a natural population of barnacle geese Branta leucopsis, we investigated individual rates of telomere length changes over two years in 34 birds between 0 and 22 years of age, covering almost 80% of the species' lifespan. We show that telomeres in this long-lived bird are very well maintained, as theoretically expected, with an average loss rate of only 5 base pairs per year among adults. We thus found no significant relationship between change in telomere length and age. However, telomeres tended to shorten at a faster pace in juveniles compared to adults. For the first time, we demonstrate a faster telomere attrition rate in females compared to males. We found no correlation between telomere loss rate and adult survival or change in body mass. Our results add further support for a link between longevity and telomere maintenance, and highlight the complexities of telomere dynamics in natural populations.

  • 1344.
    Pavlovska, Mariia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Populationsbiologi och naturvårdsbiologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för biologisk grundutbildning.
    Ukrainian Black grouse (Tetrao tetrix): Genetic diversity and population structure2012Independent thesis Advanced level (degree of Master (Two Years)), 30 poäng / 45 hpOppgave
    Abstract [en]

    Standardized, unbiased and full data on the population diversity and structure of endangered species is one of the most essential needs of conservation biology, as it gives the possibility to effectively manage the species across its distribution range. The present study is, so far, the first one focusing on the neutral and adaptive genetic diversity of Ukrainian populations of Black grouse (Tetrao tetix). It is aimed to fill in the gap in the data on the diversity of European populations of this species. The specific goals of this study are: (1) to estimate both neutral (microsatellite) and adaptive (MHC) diversity of the Northern and the Carpathian Black grouse populations, (2) to infer the population structure of Ukrainian Black grouse, (3) to study the population history of this species, (4) to compare Ukrainian populations with the European ones and estimate the rate of differentiation between them, (5) to draw conclusions about the possible management efforts of the Black grouse on the territory of Ukraine and make suggestions about the subsequent research of this species.The results illustrate that Ukrainian populations are more diverse than the European ones and highly differentiated from them. Both studied populations did not show any signs of a recent bottleneck event. Population structure of Ukrainian Black grouse was more pronounced for the neutral variation than for the adaptive one, suggesting that balancing selection is shaping the MHC diversity. Yet, the MHC differentiation between the two studied populations was still high (Dest =0.454), which could be a sign of local adaptations. Thus, it is suggested that the Northern and the Carpathian Black grouse populations should be treated as separate Management Units (MU).Black grouse population in the Carpathian Mountains appeared to be more diverse than the one in the North in terms of neutral and adaptive genetic variation. Therefore, it was suggested that the Carpathian Mountains could have been a refuge for the Black grouse during the last glaciations period. This hypothesis should be tested in the subsequent study involving more extensive sampling in both regions and inferring phylogeographical analysis of Ukrainian Black grouse population.

  • 1345. Paśko, Łukasz
    et al.
    Ericson, Per G P
    Naturhistoriska riksmuseet, Forskningsavdelningen centralt.
    Elzanowski, Andrzej
    Phylogenetic utility and evolution of indels: a study in neognathous birds.2011Inngår i: Molecular Phylogenetics and Evolution, ISSN 1055-7903, E-ISSN 1095-9513, Vol. 61, nr 3, s. 760-71Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Indels are increasingly used in phylogenetics and play a major role in genome size evolution, and yet both the phylogenetic information content of indels and their evolutionary significance remain to be better assessed. Using three presumably independently evolving nuclear gene fragments (28S rDNA, β-fibrinogen, ornithine decarboxylase) from 29 families of neognathous birds, we have obtained a topology that is in general agreement with the current molecular consensus tree, supports the monophyly of Metaves, and provides evidence for the unresolved relationships within the Charadriiformes. Based on the retrieved topology, we assess the relative impact of indels and nucleotide substitutions and demonstrate that the superposition of the two kinds of data yields a topology that could not be obtained from either data set alone. Although only two out of three gene fragments reveal the deletion bias, the combined nucleotide insertion-to-deletion ratio is 0.22, indicating a rapid decrease of intron length. The average indel fixation rate in the neognaths is 2.5 times faster than that in therian (placental) mammals of similar geologic age. As in mammals, there is a considerable variation of indel fixation rate that is 1.5 times higher in Galloanseres compared to Neoaves, and 2.4 times higher in the Rallidae compared to the average for Neoaves (8.2 times higher compared to the related Gruidae). Our results add to the evidence that indel fixation rates correlate with lineage-specific evolutionary rates.

  • 1346.
    Pecnerova, Patricia
    et al.
    Naturhistoriska riksmuseet, Enheten för bioinformatik och genetik.
    Moravec, Jiri C.
    Martinkova, Natalia
    A Skull Might Lie: Modeling Ancestral Ranges and Diet from Genes and Shape of Tree Squirrel2015Inngår i: Systematic Biology, ISSN 1063-5157, E-ISSN 1076-836X, Vol. 64, nr 6, s. 1074-1088Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Tropical forests of Central and South America represent hotspots of biological diversity. Tree squirrels of the tribe Sciurini are an excellent model system for the study of tropical biodiversity as these squirrels disperse exceptional distances, and after colonizing the tropics of the Central and South America, they have diversified rapidly. Here, we compare signals from DNA sequences with morphological signals using pictures of skulls and computational simulations. Phylogenetic analyses reveal step-wise geographic divergence across the Northern Hemisphere. In Central and South America, tree squirrels form two separate clades, which split from a common ancestor. Simulations of ancestral distributions show western Amazonia as the epicenter of speciation in South America. This finding suggests that wet tropical forests on the foothills of Andes possibly served as refugia of squirrel diversification during Pleistocene climatic oscillations. Comparison of phylogeny and morphology reveals one major discrepancy: Microsciurus species are a single clade morphologically but are polyphyletic genetically. Modeling of morphology-diet relationships shows that the only group of species with a direct link between skull shape and diet are the bark-gleaning insectivorous species of Microsciurus. This finding suggests that the current designation of Microsciurus as a genus is based on convergent ecologically driven changes in morphology.

  • 1347.
    Pedersen, Julia E.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Farmakologi.
    Evolution of acetylcholine receptors and study of the anatomy of the mouse brain reward system2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis work is divided in two parts. In the first part, I make use of the transgenic TRPV1-Cre mouse line as a tool to investigate the midbrain ventral tegmental area (VTA). By using a ChR2-EYFP construct, detailed mapping of connectivity shows that TRPV1-Cre VTA neurons innervate many brain areas such as the prefrontal cortex (PFC), ventral pallidum, bed nucleus of stria terminalis and lateral habenula. Interestingly, a mainly excitatory subcircuit from the VTA to PFC in the TRPV1-Cre mouse was identified which suggests a fast modulatory mechanism of the PFC by a VTA subpopulation. These results are discussed in the light of behavioral and neurophysiological literature. In the second part, the evolution of the vertebrate acetylcholine (ACh) receptor gene families in relation to the whole genome duplications (WGDs), also called 1R and 2R, was investigated. The nicotinic ACh receptors (nAChRs) form a complex gene family, where the members have evolved with varying rates. Our analyses combined phylogeny, intron positions and chromosomal synteny in order to elucidate the nAChR evolution in relation to the vertebrate WGDs. We found that ten ancestral nAChR genes were present prior to the WGDs. 1R and 2R then expanded this set to 19 genes, of which 16 are present in mammals today. The teleost specific WGD, 3R, further expanded the repertoire into 31 genes, of which 27 genes are present in zebrafish. The muscarinic ACh receptors (mAChRs) on the other hand form a smaller receptor family. Using the same approach, our analyses show that there were two ancestral genes present prior to the WGDs, expanding to five genes following 1R and 2R. In zebrafish, all genes retained duplicates in 3R resulting in ten mAChR genes present today. Our analyses also showed that four mAChR teleost genes have gained introns, some up to six introns. The evolutionary analyses of the receptor gene families show that all vertebrate duplication events in the AChR families, except for two among the nAChR genes, occurred through 1R, 2R and 3R, displaying the substantial impact of the WGDs on the evolution of the AChR genes.

  • 1348.
    Pedersen, Julia E.
    et al.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Bergqvist, Christina A.
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Larhammar, Dan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap.
    Evolution of the muscarinic acetylcholine receptors in vertebratesManuskript (preprint) (Annet vitenskapelig)
  • 1349.
    Pedersen, Julia E.
    et al.
    Uppsala universitet, Science for Life Laboratory, SciLifeLab. Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Farmakologi.
    Bergqvist, Christina
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Farmakologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Larhammar, Dan
    Uppsala universitet, Medicinska och farmaceutiska vetenskapsområdet, Medicinska fakulteten, Institutionen för neurovetenskap, Farmakologi. Uppsala universitet, Science for Life Laboratory, SciLifeLab.
    Evolution of vertebrate nicotinic acetylcholine receptors2019Inngår i: BMC Evolutionary Biology, ISSN 1471-2148, E-ISSN 1471-2148, Vol. 19, artikkel-id 38Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Background

    Many physiological processes are influenced by nicotinic acetylcholine receptors (nAChR), ranging from neuromuscular and parasympathetic signaling to modulation of the reward system and long-term memory. Due to the complexity of the nAChR family and variable evolutionary rates among its members, their evolution in vertebrates has been difficult to resolve. In order to understand how and when the nAChR genes arose, we have used a broad approach of analyses combining sequence-based phylogeny, chromosomal synteny and intron positions.

    Results

    Our analyses suggest that there were ten subunit genes present in the vertebrate predecessor. The two basal vertebrate tetraploidizations (1R and 2R) then expanded this set to 19 genes. Three of these have been lost in mammals, resulting in 16 members today. None of the ten ancestral genes have kept all four copies after 2R. Following 2R, two of the ancestral genes became triplicates, five of them became pairs, and three seem to have remained single genes. One triplet consists of CHRNA7, CHRNA8 and the previously undescribed CHRNA11, of which the two latter have been lost in mammals but are still present in lizards and ray-finned fishes. The other triplet consists of CHRNB2, CHRNB4 and CHRNB5, the latter of which has also been lost in mammals. In ray-finned fish the neuromuscular subunit gene CHRNB1 underwent a local gene duplication generating CHRNB1.2. The third tetraploidization in the predecessor of teleosts (3R) expanded the repertoire to a total of 31 genes, of which 27 remain in zebrafish. These evolutionary relationships are supported by the exon-intron organization of the genes.

    Conclusion

    The tetraploidizations explain all gene duplication events in vertebrates except two. This indicates that the genome doublings have had a substantial impact on the complexity of this gene family leading to a very large number of members that have existed for hundreds of millions of years.

  • 1350.
    Peedu, Elisabet
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Metapopulations dynamics and sex-specific resource allocation in Silene dioica2018Licentiatavhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Rising archipelagos provide unique settings for the study of the temporal and spatial dynamics of their biota. This offers the possibility to study the ecology and genetics of early successional processes; both between islands that differ in age and within islands when already established organisms have to keep pace with the changing environment. I have worked in the Skeppsvik Archipelago housing about 100 islands that due to land uplift vary in age, thus representing various stages of primary succession. I have utilized a naturally created metapopulation of Silene dioica, which in this archipelago is a dominant plant of the deciduous border, offering the possibility to study subpopulations on islands of different ages and in different phases of primary succession. Many plant species exist as metapopulations, which consists of many local populations which may differ in size and degree of connectivity. Metapopulations are further characterized by recurrent colorizations and extinctions of local populations, meaning that a species continually must disperse and relocate to allow for persistence in this system. For a dioecious plant species, gene flow is in the shape of seeds and pollen and to allow for the persistence of populations, it is necessary that levels of seed dispersal and pollen gene flow are enough to ensure both colonisation, establishment and subsequent population growth. Levels of seed dispersal and pollen gene flow is in turn influenced by how the two sexes partition resources between reproduction, growth and survival.

    In paper I, I combined a field survey, a common garden experiment and a nine-year demographic study to assess the demographic consequences of sex-specific resource allocation and to investigate if differential costs of reproduction may be a driver in the evolution of sexual dimorphism in dioecious Silene dioica. Significant somatic intersexual dimorphism was found with females being the larger sex, both in terms of above – and belowground biomass. Furthermore, the reproductive effort of females exceeds that of males across a growing season which largely confirms what has been observed earlier in dioecious, herbaceous plant species. According to the cost of reproduction hypothesis, high reproductive investment should result in trade-offs with somatic and/or life-history traits. Somatic trade-offs were not observed, and instead I found strong, positive associations between reproductive investment and vegetative growth in both males and females. Compensation mechanisms were found in both sexes although females are generally more efficient at compensating their reproductive costs. At the end of a flowering season, after having paid the current costs of reproduction, females are better than males at provisioning perennial roots and rosettes potentially influencing the ability to set future flower buds and winter survival. Trade-offs were found between current and future reproduction and survival, but this is condition dependent and compensation through frequency of flowering plays an important role. The cost of reproduction hypothesis appears to play some role in driving the somatic and demographic sexual dimorphisms observed in this system but sexual selection acting on males will be a fruitful avenue for future research.

    In paper II, I investigated the population genetic consequences of metapopulation dynamics in Silene dioica. The occurrence of islands in different phases of primary succession together with successional gradients across islands, makes it possible to investigate the genetic dynamics occurring in an age-structured metapopulation across several hierarchical levels. Genetic diversity and differentiation were estimated in eight young, recently colonised populations and in ten populations of an intermediate successional stage. Young populations were less genetically diverse compared to older populations, indicating that bottlenecks, created by small founding groups derived from a limited number of source populations, reduce the genetic diversity within newly founded populations. The observation of strong genetic structure both between islands and between patches with islands, indicates that gene flow is restricted across several spatial levels in this system. However, the lack of statistically significant differences in genetic differentiation between young and intermediate populations, indicates that levels of gene flow may not be high enough to reduce the genetic differentiation that arise from the initial founder event.

    The patterns of sexual dimorphism and the roles of males and females in Silene dioica have evolved to allow persistence in an ecological and population context of this species. The nature of this habitat, where islands rise up from the sea creating new environments for colonisation while at the same time, autogenic primary succession processes eventually leads to extinction, means that S. dioica continuously must relocate within successional phases for its persistence. The obvious success of this dioecious plant is apparent as it is one of the few dominant species in the deciduous border. This suggests that levels of seed dispersal and gene flow are sufficient enough to allow for establishment and persistence of island populations and that the sexual dimorphisms that have evolved in this metapopulation system act to increase levels of gene flow. The "live hard – die young" strategy, with extensive flowering bouts, which we find in the males may have evolved as a way of maintaining sufficient levels of genetic diversity in the metapopulation but will only be a possible strategy if there are continuous opportunities for re-establishments. Thus, the continuous land uplift that is occurring in the northern part of the Gulf of Bothnia may very well be a prerequisite for the long-term persistence of this dioecious, perennial plant species.

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