Browsing Naturhistorisk museum by Title

Now showing items 617-636 of 763

  • Spatiotemporal monitoring of the rare northern dragonhead (Dracocephalum ruyschiana, Lamiaceae) — SNP genotyping and environmental niche modeling herbarium specimens 
    Nygaard, Malene; Kopatz, Alexander; Speed, James David Mervyn; Martin, Michael David; Prestø, Tommy; Kleven, Oddmund; Bendiksby, Mika (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
    The species we have studied the spatiotemporal genetic change in the northern dragonhead, a plant species that has experienced a drastic population decline and habitat loss in Europe. We have added a temporal perspective ...
  • Spatiotemporal Variations in Surface Heat Loss Imply a Heterogeneous Mantle Cooling History 
    Karlsen, Krister Stræte; Conrad, Clinton Phillips; Domeier, Mathew; Trønnes, Reidar G (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
    Earth's heat budget is strongly influenced by spatial and temporal variations in surface heat flow caused by plate tectonic cycles. Here, we use a novel set of paleo‐seafloor age grids extending back to the mid‐Paleozoic ...
  • Specialized sledge dogs accompanied Inuit dispersal across the North American Arctic 
    Ameen, Carly; Feuerborn, Tatiana R.; Brown, Sarah K.; Linderholm, Anna; Hulme-Beaman, Ardern; Lebrasseur, Ophelie; Sinding, Mikkel Holger Strander; Lounsberry, Zachary T.; Lin, Audrey T.; Appelt, Martin; Bachmann, Lutz; Betts, Matthew; Britton, Kate; Darwent, John; Dietz, Rune; Fredholm, Merethe; Gopalakrishnan, Shyam; Goruinova, Olga I.; Grønnow, Bjarne; Haile, James; Hallsson, Jón Hallsteinn; Harrison, Ramona; Heide-Jørgensen, Mads-Peter; Knecht, Rick; Losey, Robert J.; Masson-MacLean, Edouard; McGovern, Thomas H.; McMagnus-Fry, Ellen; Meldgaard, Morten; Midtdal, Åslaug; Moss, Madonna L.; Nikitin, Iurii G.; Nomokonova, Tatiana; Palsdottir, Albina Hulda; Perri, Angela; Popov, Aleksandr N.; Rankin, Lisa; Reuther, Joshua D.; Sablin, Mikhail V.; Schmidt, Anne Lisbeth; Shirar, Scott; Smiarowski, Konrad; Sonne, Christian; Stiner, Mary C.; Vasyukov, Mitya; West, Catherine F.; Ween, Gro Birgit; Wennerberg, Sanne Eline; Wiig, Øystein; Woollett, James; Dalén, Love; Hansen, Anders J.; Gilbert, Marcus Thomas Pius; Sacks, Benjamin N; Frantz, Laurent A.F.; Larson, Greger; Dobney, Keith; Darwent, Christyann M.; Evin, Allowen (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2019)
    Domestic dogs have been central to life in the North American Arctic for millennia. The ancestors of the Inuit were the first to introduce the widespread usage of dog sledge transportation technology to the Americas, but ...
  • Speciation in arctic and alpine diploid plants 
    Gustafsson, A. Lovisa S. (Doctoral thesis / Doktoravhandling, 2013)
    The main objectives of this thesis are to study patterns and processes of plant speciation in arctic and alpine diploid plants. Cryptic species are here referred to as morphologically similar individuals belonging to the ...
  • Species-level divergences in multiple functional traits between the two endemic subspecies of Blue Chaffinches Fringilla teydea in Canary Islands 
    Lifjeld, Jan T; Anmarkrud, Jarl A; Calabuig, Pascual; Cooper, Joseph E J; Johannessen, Lars E; Johnsen, Arild; Kearns, Anna M; Lachlan, Robert F; Laskemoen, Terje; Marthinsen, Gunnhild; Stensrud, Even; Garcia-del-Rey, Eduardo (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2016)
    Background One of the biggest challenges in avian taxonomy is the delimitation of allopatric species because their reproductive incompatibility cannot be directly studied in the wild. Instead, reproductive ...
  • Species-specific responses of “Critically Endangered” and “Least Concern” Aloe seed germination to environmental conditions in Tanzania 
    Abihudi, Siri; Venkataramana, Pavithravani; de Boer, Hugo; Treydte, Anna C (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
    The majority of Aloe species are threatened by anthropogenic activities, trade, and the effects of climate change, but little is known on seed biology and appropriate conservation measures. Hence, understanding the germination ...
  • Spectral analysis to improve inputs to Random Forest and other boosted ensemble tree-based algorithms for detecting NYF Pegmatites in Tysfjord, Norway 
    Santos, Douglas; Cardoso-Fernandes, Joana; Lima, Alexandre; Müller, Axel; Brönner, Marco; Teodoro, Ana Cláudia (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
    As an important source of lithium and rare earth elements (REE) and other critical elements, pegmatites are of great strategic economic interest for present and future technological development. Identifying new pegmatite ...
  • Sperm adaptation in relation to salinity in three goby species 
    Lindström, Kai; Havenhand, Jon; Leder, Erica Helen; Schöld, Sofie; Svensson, Ola; Kvarnemo, Charlotta (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
    In externally fertilizing species, the gametes of both males and females are exposed to the influences of the environment into which they are released. Sperm are sensitive to abiotic factors such as salinity, but they are ...
  • Sperm divergence in a passerine contact zone: Indication of reinforcement at the gametic level 
    Albrecht, Tomas; Opletalová, Kamila; Reif, Jiri; Janousek, Vaclav; Pialek, Lubomir; Cramer, Emily Rebecca A; Johnsen, Arild; Reifova, Radka (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
    Postcopulatory sexual selection may promote evolutionary diversification in sperm form, but the contribution of between‐species divergence in sperm morphology to the origin of reproductive isolation and speciation remains ...
  • Sperm head abnormalities are associated with excessive omega-6 fatty acids in two finch species feeding on sunflower seeds 
    Støstad, Hanna Nyborg; Rowe, Melissah; Johnsen, Arild; Tomasek, Oldrich; Albrecht, Tomas; Lifjeld, Jan Terje (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
    In a rapidly changing world, it is important to understand how urban environments impact wildlife. For example, supplementary feeding of birds, though well‐intended, might have unexpected negative effects on the health of ...
  • Sperm head abnormalities are more frequent in songbirds with more helical sperm: A possible trade-off in sperm evolution 
    Støstad, Hanna Nyborg; Rowe, Melissah; Johnsen, Arild; Lifjeld, Jan Terje (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2019)
    Sperm morphology varies enormously across the animal kingdom. Whilst knowledge of the factors that drive the evolution of interspecific variation in sperm morphology is accumulating, we currently have little understanding ...
  • Sperm head morphology is associated with sperm swimming speed: a comparative study of songbirds using electron microscopy 
    Støstad, Hanna Nyborg; Johnsen, Arild; Lifjeld, Jan Terje; Rowe, Melissah (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2018)
    Sperm exhibit extraordinary levels of morphological diversification across the animal kingdom. In songbirds, sperm have a helically shaped head incorporating a distinct acrosomal membrane or “helical keel,” the form and ...
  • Sperm length divergence as a potential pre-zygotic barrier in a passerine hybrid zone 
    Cramer, Emily Rebecca A; Grønstøl, Gaute; Maxwell, Logan; Kovach, Adrienne; Lifjeld, Jan Terje (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
    The saltmarsh sparrow Ammospiza caudacuta and Nelson's sparrow A. nelsoni differ in ecological niche, mating behavior, and plumage, but they hybridize where their breeding distributions overlap. In this advanced hybrid ...
  • Sperm length variation among Afrotropical songbirds reflects phylogeny rather than adaptations to the tropical environment 
    Omotoriogun, Taiwo Crossby; Albrecht, Tomas; Gohli, Jostein; Horák, David; Johannessen, Lars Erik; Johnsen, Arild; Kreisinger, Jakub; Marki, Petter Zahl; Ottosson, Ulf; Rowe, Melissah; Sedlacek, Ondrej; Lifjeld, Jan Terje (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2020)
    Sperm cells vary tremendously in size and shape across the animal kingdom. In songbirds (Aves: Passeri), sperm have a characteristic helical form but vary considerably in size. Most of our knowledge about sperm morphology ...
  • Sperm morphology and function in passerine birds: insights from intra- and interspecific studies 
    Laskemoen, Terje (Doctoral thesis / Doktoravhandling, 2010)
    Sperm cells are the most variable animal cells, and a tremendous variation in sperm phenotypes exists among species, from minute amoeboid sperm to giant sperm in some species of fruit flies. Much effort has been devoted ...
  • Sperm morphology and performance in relation to postmating prezygotic isolation in two recently diverged passerine species 
    Poignet, Manon; Baránková, Lucie; Reif, Jiri; Stopka, Pavel; Stopková, Romana; Frolikova, Michaela; Cramer, Becky; Johnsen, Arild; Kverek, Pavel; Osiejuk, Tomasz S.; Komrskova, Katerina; Albrecht, Tomas; Reifova, Radka (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
    Abstract Divergence in sperm phenotype and female reproductive environment may be a common source of postmating prezygotic (PMPZ) isolation between species. However, compared to other reproductive barriers it has received ...
  • Sperm morphology, sperm motility and paternity success in the bluethroat (Luscinia svecica) 
    Sætre, Camilla Lo Cascio; Johnsen, Arild; Stensrud, Even; Cramer, Emily Rebecca A (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2018)
    Postcopulatory sexual selection may select for male primary sexual characteristics like sperm morphology and sperm motility, through sperm competition or cryptic female choice. However, how such characteristics influence ...
  • Sperm Numbers as a Paternity Guard in a Wild Bird 
    Rowe, Melissah; van Oort, Annabel; Brouwer, Lyanne; Lifjeld, Jan Terje; Webster, Michael S.; Welklin, Joseph F.; Baldassarre, Daniel T. (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2022)
    Sperm competition is thought to impose strong selection on males to produce competitive ejaculates to outcompete rival males under competitive mating conditions. Our understanding of how different sperm traits influence ...
  • Sperm performance in conspecific and heterospecific female fluid 
    Cramer, Emily Rebecca A; Stensrud, Even; Marthinsen, Gunnhild; Hogner, Silje; Johannessen, Lars Erik; Laskemoen, Terje; Eybert, Marie-Christine; Slagsvold, Tore; Lifjeld, Jan Terje; Johnsen, Arild (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2016)
    Divergent sexual selection within allopatric populations may result in divergent sexual phenotypes, which can act as reproductive barriers between populations upon secondary contact. This hypothesis has been most tested ...
  • Sperm performance limits the reproduction of an invasive fish in novel salinities 
    Green, Leon; Niemax, Jan; Herrmann, Jens-Peter; Temming, Axel; Behrens, Jane W.; Havenhand, Jon; Leder, Erica Helen; Kvarnemo, Charlotta (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
    Aim The few fish species able to reproduce across wide osmotic ranges either plastically acclimate sperm performance to, or are locally adapted to, different salinities. The invasive round goby (Neogobius melanostomus) ...