Gaute Grønstøl

• Cramer, Emily R. A.; Grønstøl, Gaute; Benham, Phred M.; Cicero, Carla; Bowie, Rauri C. K. & Tobiansky, Daniel J. [Vis alle 7 forfattere av denne artikkelen] (2025). Unusual Sperm Morphology in Two Sedentary Songbird Species. Ecology and Evolution. 15(8). doi: 10.1002/ece3.71873. Fulltekst i vitenarkiv Vis sammendrag

  Sperm morphology can differ dramatically among closely related species. Within songbirds, the typical filiform sperm has a slender, corkscrew‐shaped head and an elongated midpiece coiled around the flagellum. However, three songbird species are known to have an unusual tadpole‐like sperm morphology with a round or ellipsoid head and short, uncoiled midpiece, which may arise developmentally via neoteny. Here, we describe tadpole‐like sperm phenotypes from two additional songbird species, the white‐breasted nuthatch ( Sitta carolinensis ) and the wrentit ( Chamaea fasciata ). These five species with tadpole‐like sperm share several ecological characteristics that can inform hypotheses for the evolution of this unusual phenotype: They are largely non‐migratory, form long‐lasting pair bonds, and have high paternal investment, small testes (no data for wrentit), and short and highly variable sperm lengths. These characteristics could indicate particular natural selection pressures driving physiological states such as low testicular testosterone levels. Additionally, though direct measures of female promiscuity are lacking in these species, these characteristics are consistent with weak post‐copulatory sexual selection. Further study of these similar yet independent evolutionary events, across all levels of analysis, would be valuable for understanding how such dramatic shifts in phenotype evolve.

• Lifjeld, Jan Terje; Garcia-del-Rey, Eduardo; Grønstøl, Gaute; Valle, Carlos A & Leder, Erica Helen (2025). Weak sperm differentiation in Darwin’s finches. Biological Journal of the Linnean Society. ISSN 0024-4066. 146(2). doi: 10.1093/biolinnean/blaf103. Fulltekst i vitenarkiv Vis sammendrag

  Spermatozoa may provide insights into the evolutionary history, reproductive isolation, and mating systems of species. Here we combine sperm and genomic data to conduct the first comparative analysis of sperm differentiation among Darwin’s finches, an iconic adaptive radiation with considerable gene flow across species borders. All eight study species had the typical form of songbird spermatozoa, but shorter than most other species in the Thraupidae family. There was no detectable differentiation in sperm length among four ground finch species (Geospiza) and two tree finch species (Camarhynchus). In both genera, autosomal single nucleotide polymorphisms (SNPs) revealed signatures of genetic admixture. The grey warbler-finch Certhidea fusca and the vegetarian finch Platyspiza crassirostris had significantly shorter sperm than the sister genera Geospiza and Camarhynchus from which they diverged about 0.90 and 0.43 Mya, respectively. The largest intergeneric divergences in sperm length were of the same magnitude as divergences observed within the speciation continuum in other songbirds over similar time spans. Relatively high among-male variation in sperm length indicates a moderate-to-low level of extrapair paternity and a divergence rate in sperm length that is lower than in more promiscuous songbirds. We conclude that sperm size evolution is too slow to drive prezygotic isolation in this radiation.

• Lifjeld, Jan Terje; Hernando, Miguel de Gabriel; Marcos, Benito Fuertes; Grønstøl, Gaute; Anmarkrud, Jarl Andreas & Matschiner, Michael [Vis alle 7 forfattere av denne artikkelen] (2023). Rapid sperm length divergence in a polygynandrous passerine: a mechanism of cryptic speciation? Evolution. ISSN 0014-3820. 77(11), s. 2352–2364. doi: 10.1093/evolut/qpad146. Fulltekst i vitenarkiv
• Grønstøl, Gaute; Danielsen, Marie; Cramer, Becky; Johannessen, Lars Erik; Johnsen, Arild & Whittington, Emma [Vis alle 7 forfattere av denne artikkelen] (2022). Effects of fixatives and storage duration on avian sperm morphology. Journal of Ornithology. ISSN 2193-7192. 164(1), s. 171–181. doi: 10.1007/s10336-022-02015-x. Fulltekst i vitenarkiv Vis sammendrag

  Abstract Sperm cells are variable both within and among species. To be able to accurately measure sperm cells and understand their function, it is important that sperm cells are preserved in a manner that maintains their structural integrity. Formalin is a widely used fixative and storage medium for sperm cells, but few studies have examined the effect of fixation and long-term storage on their morphological integrity. Ethanol is also a common fixation and storage agent for tissue samples, and here we examine if fixation and storage in formalin or ethanol alters sperm cell size and structural integrity. We found no significant effects of the fixation process on fresh sperm cells fixed in formalin or ethanol. Further, there were no consistent length changes in sperm cells stored in formalin or ethanol over a period of 227 days, or in sperm cells stored in formalin for three years. A comparison across 13–14 years of storage time showed a small but significant reduction in sperm cell length of 0.93%. Furthermore, sperm cells initially fixed in formalin remained quite stable in dry storage on glass slides for a minimum of six months (we found a mean reduction in sperm cell length of 0.18% after 6 months). The proportion of sperm cells with head damage was, however, much higher for samples stored in ethanol than for those stored in formalin. Overall, 70% of sperm cells had acrosome damage in ethanol versus only 3% in formalin. Finding intact sperm cells for measuring length, therefore, required greater effort in ethanol samples than in formalin samples. Our findings indicate that use of sperm cells from long-term storage for the study of sperm morphometrics is justified for either fixative, although formalin clearly preserves the sperm cells better.

• Cramer, Becky; Grønstøl, Gaute & Lifjeld, Jan Terje (2022). Flagellum tapering and midpiece volume in songbird spermatozoa. Journal of morphology. ISSN 0362-2525. 283(12), s. 1577–1589. doi: 10.1002/jmor.21524. Fulltekst i vitenarkiv Vis sammendrag

  In contrast to numerous studies on spermatozoa length, relatively little work focuses on the width of spermatozoa, and particularly the width of the midpiece and flagellum. In flagellated spermatozoa, the flagellum provides forward thrust while energy may be provided via mitochondria in the midpiece and/or through glycolysis along the flagellum itself. Longer flagella may be able to provide greater thrust but may also require stronger structural features and more or larger mitochondria to supply sufficient energy. Here, we use scanning electron microscopy to investigate the ultrastructure of spermatozoa from 55 passerine species in 26 taxonomic families in the Passerides infraorder. Our data confirm the qualitative observation that the flagellum tapers along its length, and we show that longer flagella are wider at the neck. This pattern is similar to mammals, and likely reflects the need for longer cells to be stronger against shearing forces. We further estimate the volume of the mitochondrial helix and show that it correlates well with midpiece length, supporting the use of midpiece length as a proxy for mitochondrial volume, at least in betweenspecies studies where midpiece length is highly variable. These results provide important context for understanding the evolutionary correlations among different sperm cell components and dimensions.

• Cramer, Emily Rebecca A; Grønstøl, Gaute; Maxwell, Logan; Kovach, Adrienne & Lifjeld, Jan Terje (2021). Sperm length divergence as a potential pre-zygotic barrier in a passerine hybrid zone. Ecology and Evolution. 11(14), s. 9489–9497. doi: 10.1002/ece3.7768. Fulltekst i vitenarkiv Vis sammendrag

  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 zone, past interbreeding and current backcrossing result in substantial genomic introgression in both directions, although few hybrids are currently produced in most locations. However, because both species are nonterritorial and have only brief male–female interactions, it is difficult to determine to what extent assortative mating explains the low frequency of hybrid offspring. Since females often copulate with multiple males, a role of sperm as a postcopulatory prezygotic barrier appears plausible. Here, we show that sperm length differs between the two species in the hybrid zone, with low among-male variation consistent with strong postcopulatory sexual selection on sperm cells. We hypothesize that divergence in sperm length may constitute a reproductive barrier between species, as sperm length co-evolves with the size of specialized female sperm storage tubules. Sperm does not appear to act as a postzygotic barrier, as sperm from hybrids was unexceptional.

• Grønstøl, Gaute (2018). Polygyny Threshold Model. I Vonk, Jennifer & Schackelford, Todd (Red.), Encyclopedia of Animal Cognition and Behavior. Springer. ISSN 9783319478296. doi: 10.1007/978-3-319-47829-6_460-1. Fulltekst i vitenarkiv
• Heimstad, Eldbjørg Sofie; Grønstøl, Gaute; Hetland, Karl Torstein; Alarcon, Javier Martinez; Rylander, Charlotta & Mariussen, Espen (2016). Schools taking part in a research project investigating dioxins in fish. I Kallenborn, Roland (Red.), Implications and Consequences of Anthropogenic Pollution in Polar Environments. Springer Science+Business Media B.V.. ISSN 9783642123146. s. 75–86. doi: 10.1007/978-3-642-12315-3_6. Fulltekst i vitenarkiv
• Byrkjedal, Ingvar; Grønstøl, Gaute & Lislevand, Terje (2016). Possible resource-defence polygyny in the extinct Rodrigues Solitaire Pezophaps solitaria (Columbidae: Raphini). IBIS. ISSN 0019-1019. 158, s. 199–201. doi: 10.1111/ibi.12329. Fulltekst i vitenarkiv
• Grønstøl, Gaute; Blomqvist, Donald; Pauliny, Angela & Wagner, Richard H. (2015). Kin selection and polygyny: Can relatedness lower the polygyny threshold? Royal Society Open Science. 2:140409(6). doi: 10.1098/rsos.140409. Fulltekst i vitenarkiv Vis sammendrag

  Resource polygyny incurs costs of having to share breeding resources for female breeders. When breeding with a relative, however, such costs may be lessened by indirect fitness benefits through kin selection, while benefits from mutualistic behaviour, such as communal defence, may increase. If so, females should be less resistant to sharing a territory with a related female than with a non-related one. We investigated whether kin selection may lower the threshold of breeding polygynously, predicting a closer relatedness between polygynous females breeding on the same territory than between females breeding on different territories. Northern lapwings, Vanellus vanellus, are suitable for testing this hypothesis as they are commonly polygynous, both sexes take part in nest defence, and the efficiency of nest defence increases with the number of defenders. Using an index of relatedness derived from DNA fingerprinting, we found that female lapwings that shared polygynous dyads were on average twice as closely related as were random females. Furthermore, relatedness did not correlate with distance between breeders, indicating that our findings cannot be explained by natal philopatry alone. Our results suggest that the polygyny threshold in lapwings may be lowered by inclusive fitness advantages of kin selection.

• Heimstad, Eldbjørg Sofie; Grønstøl, Gaute; Hetland, Karl Torstein; Alarcon, Javier Martinez; Rylander, Charlotta & Mariussen, Espen (2015). A survey of dioxin-like contaminants in fish from recreational fishing. Environmental Monitoring and Assessment. ISSN 0167-6369. 187. doi: 10.1007/s10661-015-4728-7. Fulltekst i vitenarkiv Vis sammendrag

  The dioxin and dioxin-like compounds are regarded as one of the most toxic group of environmental contaminants. Food for the commercial market is regularly monitored for their dioxin levels and the concentration allowed in food is strictly regulated. Less is known about locally caught fish from recreational fishing, which is often brought home for consumption. This can be fish caught from nearby lakes or streams or fish with marine origin close to industrial areas or harbours that are not regularly monitored for their dioxin levels. In this study, we established collaboration with schools in 13 countries. We received 203 samples of 29 different fish species of which Atlantic cod was the most abundant followed by brown trout and pollock. In general, the majority of samples from the participating countries had low concentrations (between 0.1 and 0.2 pg/g chemical-activated luciferase gene expression toxic equivalency wet weight (CALUX TEQ w.w.)) of dioxins and dioxin-like PCBs. Only 18 samples had concentrations above 1 pg/g CALUX TEQ w.w., and only 2 dab samples had concentration above maximum levels set by the European Commission. The Atlantic cod samples showed a significant reduction in the concentrations of dioxins with increasing latitude indicating less contamination of dioxin and dioxin-like compounds in the north of Norway. The results indicate that a moderate consumption of self-caught fish at presumed non-contaminated sites does not represent a major risk for exposure to dioxins or dioxin-like compounds at concentrations associated with adverse health effects. Recreational fishermen should, however, obtain knowledge about local fish consumption advice.

• Grønstøl, Gaute; Lislevand, Terje & Byrkjedal, Ingvar (2014). Resident female northern lapwings Vanellus vanellus fight to exclude settlement by secondary females. IBIS. ISSN 0019-1019. 156(2), s. 461–465. doi: 10.1111/ibi.12132. Fulltekst i vitenarkiv
• Grønstøl, Gaute; Lislevand, Terje; Byrkjedal, Ingvar & Hafsmo, Jo Esten (2013). Chick growth and survival in northern lapwings Vanellus vanellus indicate that secondary females do the best of a bad job. Journal of Avian Biology. ISSN 0908-8857. 44(4), s. 376–382. doi: 10.1111/j.1600-048X.2013.05811.x. Fulltekst i vitenarkiv
• Byrkjedal, Ingvar; Lislevand, Terje & Grønstøl, Gaute (2013). Rapid sampling of males and territories by female northern lapwing, Vanellus vanellus. The Wilson Journal of Ornithology. ISSN 1559-4491. 125(4), s. 809–811. doi: 10.1676/13-072.1. Fulltekst i vitenarkiv
• Lislevand, Terje; Byrkjedal, Ingvar & Grønstøl, Gaute (2009). Dispersal and age at first breeding in Norwegian Northern Lapwings (Vanellus vanellus). Ornis Fennica. ISSN 0030-5685. 86(1), s. 11–17. Fulltekst i vitenarkiv
• Grønstøl, Gaute; Myking, Ole Langeland; Lislevand, Terje & Byrkjedal, Ingvar (2007). Plasma testosterone levels of incubating female northern lapwings Vanellus vanellus. Ornis Norvegica. 30, s. 124–126. doi: 10.15845/on.v30i0.176. Fulltekst i vitenarkiv
• Grønstøl, Gaute; Blomqvist, Donald & Wagner, Richard H. (2006). The importance of genetic evidence for identifying intra‐specific brood parasitism. Journal of Avian Biology. ISSN 0908-8857. 37, s. 197–199. doi: 10.1111/j.2006.0908-8857.03574.x. Fulltekst i vitenarkiv
• Lislevand, Terje; Byrkjedal, Ingvar; Grønstøl, Gaute; Hafsmo, Jo Esten; Kallestad, Geir R. & Larsen, Vegard Ankarstrand (2004). Incubation Behaviour in Northern Lapwings: Nocturnal Nest Attentiveness and Possible Importance of Individual Breeding Quality. Ethology. ISSN 0179-1613. 110(3), s. 177–192. doi: 10.1111/j.1439-0310.2004.00967.x. Fulltekst i vitenarkiv
• Grønstøl, Gaute (2003). Mate-sharing costs in polygynous Northern Lapwings. IBIS. ISSN 0019-1019. 145(2), s. 203–211. doi: 10.1046/j.1474-919X.2003.00141.x. Fulltekst i vitenarkiv
• Grønstøl, Gaute; Byrkjedal, Ingvar & Fiksen, Øyvind (2003). Predicting polygynous settlement while incorporating varying female competitive strength. Behavioral Ecology. ISSN 1045-2249. 14(2), s. 257–267. doi: 10.1093/beheco/14.2.257. Fulltekst i vitenarkiv
• Lislevand, Terje; Byrkjedal, Ingvar; Grønstøl, Gaute & Hafsmo, Jo Esten (2001). Mate replacement and male brood adoption in Lapwings Vanellus vanellus. The Wader Study Group Bulletin. ISSN 0260-3799. 95, s. 55–58. Fulltekst i vitenarkiv
• Hafsmo, Jo Esten; Byrkjedal, Ingvar; Grønstøl, Gaute & Lislevand, Terje (2001). Simultaneous tetragyny in Northern Lapwing Vanellus vanellus. Bird Study. ISSN 0006-3657. 48(1), s. 124–125. doi: 10.1080/00063650109461210. Fulltekst i vitenarkiv
• Byrkjedal, Ingvar; Grønstøl, Gaute; Hafsmo, Jo Esten & Lislevand, Terje (2000). Chick punishment and chick adoption in Northern Lapwings. Ornis Fennica. ISSN 0030-5685. 77(2), s. 89–92. Fulltekst i vitenarkiv
• Grønstøl, Gaute; Solhøy, Torstein & Løyning, Mass Kåre (2000). A comparison of mustard, household detergent and formalin as vermifuges for earthworm sampling. Fauna Norvegica. ISSN 1502-4873. 20, s. 27–30. Fulltekst i vitenarkiv
• Grønstøl, Gaute; Byrkjedal, Ingvar; Hafsmo, Jo Esten & Lislevand, Terje (1999). Northern Lapwing Vanellus vanellus copulating with a grass turf. Ornis Norvegica. 22(1), s. 60–62. Fulltekst i vitenarkiv
• Grønstøl, Gaute & Pedersen, Kjell Magne (1997). Neighbour interference in Lapwing Vanellus vanellus nest defence. Ornis Fennica. ISSN 0030-5685. 74(1), s. 59–61. Fulltekst i vitenarkiv
• Byrkjedal, Ingvar; Grønstøl, Gaute; Lislevand, Terje; Pedersen, Kjell Magne; Sandvik, Heidi & Stalheim, Synnøve (1997). Mating system and territory in Lapwings Vanellus vanellus. IBIS. ISSN 0019-1019. 139(1), s. 129–137. doi: 10.1111/j.1474-919X.1997.tb04512.x. Fulltekst i vitenarkiv
• Grønstøl, Gaute (1997). Correlates of Egg-Size Variation in Polygynously Breeding Northern Lapwings. The AUK: A Quarterly Journal of Ornithology. ISSN 0004-8038. 114(3), s. 507–512. doi: 10.2307/4089255. Fulltekst i vitenarkiv
• Grønstøl, Gaute (1996). Aerobatic components in the song-flight display of male Lapwings Vanellus vanellus as cues in female choice. Ardea. ISSN 0373-2266. 84(1), s. 45–55. Fulltekst i vitenarkiv
• Flåøyen, Arne; Skaare, Janneche U & Grønstøl, Gaute (1994). Aldrin epoxidase and 7-ethoxyresorufin-O-deethylase (EROD) activity in livers from lambs of three different breeds of Norwegian sheep. Veterinary research communications. ISSN 0165-7380. 18(3), s. 169–174. doi: 10.1007/BF01839265. Fulltekst i vitenarkiv

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• Grønstøl, Gaute (2020). Vipa – kamp og kurtise i kulturmarka. Eget forlag. ISBN 9788269225709. 124 s. Fulltekst i vitenarkiv

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• Grønstøl, Gaute (2026). Vipa: Levesett og krav til omgivelser. Fulltekst i vitenarkiv
• Grønstøl, Gaute (2025). Hekkebiologien til vipe og kartlegging av hekkegrupper. Fulltekst i vitenarkiv Vis sammendrag

  Foredrag om vipe hos Nedre Glomma Fugleforening

• Grønstøl, Gaute (2024). Hekkebiologien til vipe, og litt om kartlegging av hekkegrupper. Fulltekst i vitenarkiv Vis sammendrag

  Foredrag om vipe hos Indre Østfold fugleforening, Rakkestad kommunestyresal, 20.03.2024.

• Whittington, Emma; Cramer, Becky; Grønstøl, Gaute; Leder, Erica Helen; Johnsen, Arild & Lifjeld, Jan Terje (2023). Comparative proteomics of the perivitelline layer - the site of avian sperm-egg interaction. Fulltekst i vitenarkiv
• Grønstøl, Gaute (2022). Hekkebiologien til vipe, og litt om kartlegging av hekkegrupper. Fulltekst i vitenarkiv Vis sammendrag

  Fagseminar. Kan vipa reddast? 17.03.2022. Herdla Museum. Arrangert av Statsforvaltaren og BirdLife Hordaland.

• Cramer, Becky; Grønstøl, Gaute; Maxwell, Logan; Kovach, Adrienne & Lifjeld, Jan Terje (2021). Sperm divergence as a potential reproductive barrier in Ammospiza sparrows (and other passerines). Fulltekst i vitenarkiv
• Grønstøl, Gaute (2021). Vipa – kamp og kurtise i kulturmarka. Fulltekst i vitenarkiv Vis sammendrag

  Norge rundt med Nasjonalmuseet. Hannah Ryggens 'Vipa på Ørlandet' returnerer til Ørland. 02.09.2021. Besøkssenter våtmark Ørland. Arrangert av Nasjonalmuseet.

• Grønstøl, Gaute (2021). Vipa og landbruket. Fulltekst i vitenarkiv Vis sammendrag

  Åpningskonferansen for Besøkssenter våtmark Ørland. 02.09.2021. Arrangert av Ørlandet kommune.

• Heimstad, Eldbjørg Sofie; Grønstøl, Gaute; Hetland, Karl Torstein; Alarcon, Javier Martinez; Rylander, Charlotta & Mariussen, Espen (2017). Schools taking part in a research project investigating dioxins in fish. Fulltekst i vitenarkiv
• Lislevand, Terje; Byrkjedal, Ingvar & Grønstøl, Gaute (2016). Idyll og konflikt i vipenes familieliv. Naturen. ISSN 0028-0887. 140, s. 131–139. Fulltekst i vitenarkiv
• Grønstøl, Gaute; Blomqvist, Donald & Wagner, Richard H. (2005). Hekkedynamikk og produksjon hos viper på Öland. Calidris. ISSN 0346-9395. 2(28). Fulltekst i vitenarkiv
• Grønstøl, Gaute; Blomqvist, Donald & Wagner, Richard H. (2003). Hekkebiologien hos Vipe - med resultater fra undersøkelser gjort på Öland våren 2003. Calidris. ISSN 0346-9395. 2(3), s. 18–27. Fulltekst i vitenarkiv
• Lislevand, Terje; Byrkjedal, Ingvar & Grønstøl, Gaute (2002). Vipenes atferd og levesett i hekketiden. Vår Fuglefauna. ISSN 0332-5601. 25(2), s. 52–58. Fulltekst i vitenarkiv
• Grønstøl, Gaute (2001). Sexual conflicts and mating strategies in the polygynous lapwing Vanellus vanellus. Dr. scient. thesis. Universitetet i Bergen. Fulltekst i vitenarkiv
• Grønstøl, Gaute (1994). Aerobatic components in the songflight display of male lapwings (Vanellus vanellus L.) as indicators of male quality in female choice. Cand. scient. thesis. Universitetet i Bergen. Fulltekst i vitenarkiv

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