Browsing Museene by Author "Laskemoen, Terje"

Now showing items 1-10 of 10

  • Deep sympatric mitochondrial divergence without reproductive isolation in the common redstart Phoenicurus phoenicurus 
    Hogner, Silje; Laskemoen, Terje; Lifjeld, Jan Terje; Porkert, Jiri; Kleven, Oddmund; Albayrak, Tamer; Kabasakal, Bekir; Johnsen, Arild (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2012)
    Mitochondrial DNA usually shows low sequence variation within and high sequence divergence among species, which makes it a useful marker for phylogenetic inference and DNA barcoding. A previous study on the common redstart ...
  • Early diversification of sperm size in the evolutionary history of the old world leaf warblers (Phylloscopidae) 
    K, Supriya; Rowe, Melissah; Laskemoen, Terje; Mohan, Dhananjai; Price, Trevor; Lifjeld, Jan Terje (Journal article / Tidsskriftartikkel / SubmittedVersion, 2016)
    Sperm morphological traits are highly variable among species and are commonly thought to evolve by post-copulatory sexual selection. However, little is known about the evolutionary dynamics of sperm morphology, and whether ...
  • Longer Sperm Swim More Slowly in the Canary Islands Chiffchaff 
    Cramer, Emily Rebecca A; Garcia-del-Rey, Eduardo; Johannessen, Lars Erik; Laskemoen, Terje; Marthinsen, Gunnhild; Johnsen, Arild; Lifjeld, Jan Terje (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2021)
    Sperm swimming performance affects male fertilization success, particularly in species with high sperm competition. Understanding how sperm morphology impacts swimming performance is therefore important. Sperm swimming ...
  • No Evidence for Pre-Copulatory Sexual Selection on Sperm Length in a Passerine Bird 
    Lifjeld, Jan Terje; Laskemoen, Terje; Kleven, Oddmund; Pedersen, Anne Tiril Myhre; Lampe, Helene M.; Rudolfsen, Geir; Schmoll, Tim; Slagsvold, Tore (Journal article / Tidsskriftartikkel / PublishedVersion; Peer reviewed, 2012)
    There is growing evidence that post-copulatory sexual selection, mediated by sperm competition, influences the evolution of sperm phenotypes. Evidence for pre-copulatory sexual selection effects on sperm traits, on 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 ...
  • 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 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 size evolution in African greenbuls (Passeriformes: Pycnonotidae) 
    Omotoriogun, Taiwo Crossby; Albrecht, Tomas; Hořak, David; Laskemoen, Terje; Ottosson, Ulf; Rowe, Melissah; Sedlacek, Ondrej; Lifjeld, Jan Terje (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2016)
    Sperm morphology is highly diversified across the animal kingdom and recent comparative evidence from passerine birds suggests that postcopulatory sexual selection is a significant driver of sperm evolution. In the present ...
  • Variation in sperm morphology among Afrotropical sunbirds 
    Omotoriogun, Taiwo Crossby; Laskemoen, Terje; Rowe, Melissah; Albrecht, Tomáš; Bowie, Rauri C.K.; Sedláček, Ondřej; Hořak, David; Ottosson, Ulf; Lifjeld, Jan Terje (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2016)
    Birds show considerable variation in sperm morphology. Closely related species and subspecies can show diagnostic differences in sperm size. There is also variation in sperm size among males within a population, and recent ...
  • Weak geographical structure in sperm morphology across the range of two willow warbler Phylloscopus trochilus subspecies in Scandinavia 
    Støstad, Hanna Nyborg; Rekdal, Silje Larsen; Kleven, Oddmund; Laskemoen, Terje; Marthinsen, Gunnhild; Johnsen, Arild; Lifjeld, Jan Terje (Journal article / Tidsskriftartikkel / AcceptedVersion; Peer reviewed, 2016)
    Sperm morphology is highly diversified among species and at higher taxonomic levels. In birds, there is also increasing evidence of geographical differentiation in sperm traits within species, especially in those with ...