Ivar Folstad

6.7k total citations · 1 hit paper
72 papers, 5.3k citations indexed

About

Ivar Folstad is a scholar working on Ecology, Evolution, Behavior and Systematics, Ecology and Physiology. According to data from OpenAlex, Ivar Folstad has authored 72 papers receiving a total of 5.3k indexed citations (citations by other indexed papers that have themselves been cited), including 51 papers in Ecology, Evolution, Behavior and Systematics, 23 papers in Ecology and 22 papers in Physiology. Recurrent topics in Ivar Folstad's work include Animal Behavior and Reproduction (45 papers), Reproductive biology and impacts on aquatic species (22 papers) and Fish Ecology and Management Studies (18 papers). Ivar Folstad is often cited by papers focused on Animal Behavior and Reproduction (45 papers), Reproductive biology and impacts on aquatic species (22 papers) and Fish Ecology and Management Studies (18 papers). Ivar Folstad collaborates with scholars based in Norway, Sweden and United States. Ivar Folstad's co-authors include Andrew J. Karter, Kjell Einar Erikstad, Sveinn Are Hanssen, Frode Skarstein, Geir Rudolfsen, Dennis Hasselquist, Claus Wedekind, Lars Figenschou, Arne C. Nilssen and Odd Halvorsen and has published in prestigious journals such as SHILAP Revista de lepidopterología, The American Naturalist and Ecology Letters.

In The Last Decade

Ivar Folstad

71 papers receiving 4.9k citations

Hit Papers

Parasites, Bright Males, and the Immunocompetence Handicap 1992 2026 2003 2014 1992 500 1000 1.5k 2.0k
What are hit papers?

Hit papers significantly outperform the citation benchmark for their cohort. A paper qualifies if it has ≥500 total citations, achieves ≥1.5× the top-1% citation threshold for papers in the same subfield and year (this is the minimum needed to enter the top 1%, not the average within it), or reaches the top citation threshold in at least one of its specific research topics.

  1. Parasites, Bright Males, and the Immunocompetence Handicap
    1992 2.2k citations Ivar Folstad, Andrew J. Karter The American Naturalist profile →

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Ivar Folstad Norway 32 3.3k 2.0k 762 746 736 72 5.3k
Ton G. G. Groothuis Netherlands 48 5.1k 1.5× 3.4k 1.6× 725 1.0× 1.0k 1.4× 989 1.3× 205 7.8k
Andrea Pilastro Italy 47 4.7k 1.4× 2.2k 1.1× 1.1k 1.5× 1.3k 1.8× 232 0.3× 145 6.1k
Robert Montgomerie Canada 56 6.4k 1.9× 4.5k 2.2× 1.5k 2.0× 1.6k 2.1× 472 0.6× 173 8.8k
Michael C. Moore United States 44 4.1k 1.2× 1.7k 0.8× 489 0.6× 541 0.7× 487 0.7× 116 5.9k
Hubert Schwabl United States 46 6.1k 1.8× 4.7k 2.3× 485 0.6× 838 1.1× 1.6k 2.2× 131 7.5k
Theo C. M. Bakker Germany 39 3.9k 1.2× 1.5k 0.8× 1.5k 2.0× 1.1k 1.5× 161 0.2× 156 5.6k
Ellen D. Ketterson United States 57 8.1k 2.5× 5.7k 2.8× 564 0.7× 1.5k 2.0× 1.2k 1.7× 186 10.9k
Michaela Hau Germany 48 4.3k 1.3× 3.1k 1.5× 390 0.5× 587 0.8× 551 0.7× 111 6.3k
Raine Kortet Finland 40 2.1k 0.6× 1.3k 0.6× 561 0.7× 1.1k 1.4× 406 0.6× 152 4.3k
Anne Peters Australia 40 3.6k 1.1× 2.8k 1.4× 522 0.7× 613 0.8× 440 0.6× 122 5.3k

Countries citing papers authored by Ivar Folstad

Since Specialization
Citations

This map shows the geographic impact of Ivar Folstad's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Ivar Folstad with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Ivar Folstad more than expected).

Fields of papers citing papers by Ivar Folstad

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Ivar Folstad. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Ivar Folstad. The network helps show where Ivar Folstad may publish in the future.

Co-authorship network of co-authors of Ivar Folstad

This figure shows the co-authorship network connecting the top 25 collaborators of Ivar Folstad. A scholar is included among the top collaborators of Ivar Folstad based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Ivar Folstad. Ivar Folstad is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Folstad, Ivar, et al.. (2018). Do mothers also “manipulate” grandparental care?. PeerJ. 6. e5924–e5924. 2 indexed citations
2.
Rudolfsen, Geir, et al.. (2015). Own, but not foreign seminal fluid inhibits sperm activation in a vertebrate with external fertilization. Frontiers in Ecology and Evolution. 3. 8 indexed citations
3.
Folstad, Ivar, et al.. (2013). Ranking Fluctuating Asymmetry in a Dot Figure and the Significant Impact of Imagining a Face. Perception. 42(3). 321–329. 6 indexed citations
4.
Figenschou, Lars, Ivar Folstad, Geir Rudolfsen, et al.. (2012). The relative effect of parasites and social status on sperm traits in Arctic charr. Behavioral Ecology. 24(2). 497–504. 7 indexed citations
5.
Rudolfsen, Geir, et al.. (2011). Is the adipose fin and the lower jaw (kype) related to social dominance in male Arctic charr Salvelinus alpinus?. Journal of Fish Biology. 79(4). 1076–1083. 9 indexed citations
6.
Rødven, Rolf, et al.. (2009). Parasite intensity and fur coloration in reindeer calves – contrasting artificial and natural selection. Journal of Animal Ecology. 78(3). 600–607. 11 indexed citations
7.
Rudolfsen, Geir, et al.. (2008). Sperm velocity and its relation to social status in Arctic charr (Salvelinus alpinus). Animal Reproduction Science. 115(1-4). 231–237. 20 indexed citations
8.
Folstad, Ivar, et al.. (2007). Zebra stripes as an amplifier of individual quality. Annales Zoologici Fennici. 44(5). 368–376. 8 indexed citations
9.
Folstad, Ivar, et al.. (2006). Do the fastest sperm within an ejaculate swim faster in subordinate than in dominant males of Arctic char?. Canadian Journal of Zoology. 84(7). 1019–1024. 22 indexed citations
10.
Rudolfsen, Geir, et al.. (2005). Rapid adjustments of sperm characteristics in relation to social status. Proceedings of the Royal Society B Biological Sciences. 273(1584). 325–332. 147 indexed citations
11.
Hagen, Snorre B., et al.. (2004). Autumn coloration as a signal of tree condition. Proceedings of the Royal Society B Biological Sciences. 271(suppl_4). S184–5. 24 indexed citations
12.
Hanssen, Sveinn Are, et al.. (2004). Immune Function and Organochlorine Pollutants in Arctic Breeding Glaucous Gulls. Archives of Environmental Contamination and Toxicology. 47(4). 530–541. 71 indexed citations
13.
Hanssen, Sveinn Are, Ivar Folstad, & Kjell Einar Erikstad. (2003). Reduced immunocompetence and cost of reproduction in common eiders. Oecologia. 136(3). 457–464. 77 indexed citations
14.
Folstad, Ivar, et al.. (1997). Reindeer antlers: visual indicators of individual quality?. Oecologia. 110(4). 501–507. 56 indexed citations
15.
Folstad, Ivar, et al.. (1997). The effect of parasites on courtship dance in threespine sticklebacks: more than meets the eye?. Canadian Journal of Zoology. 75(4). 589–594. 23 indexed citations
16.
Arneberg, Per, Ivar Folstad, & Andrew J. Karter. (1996). Gastrointestinal nematodes depress food intake in naturally infected reindeer. Parasitology. 112(2). 213–219. 59 indexed citations
17.
Wedekind, Claus & Ivar Folstad. (1994). Adaptive or Nonadaptive Immunosuppression by Sex Hormones?. The American Naturalist. 143(5). 936–938. 235 indexed citations
18.
Anderson, John R., Arne C. Nilssen, & Ivar Folstad. (1994). Mating behavior and thermoregulation of the reindeer warble fly,Hypoderma tarandi L. (Diptera: Oestridae). Journal of Insect Behavior. 7(5). 679–706. 30 indexed citations
19.
Karter, Andrew J., Ivar Folstad, & John R. Anderson. (1992). Abiotic factors influencing embryonic development, egg hatching, and larval orientation in the reindeer warble fly, Hypoderma tarandi. Medical and Veterinary Entomology. 6(4). 355–362. 16 indexed citations
20.
Folstad, Ivar, Arne C. Nilssen, Odd Halvorsen, & Johan Andersen. (1991). Parasite avoidance: the cause of post-calving migrations in Rangifer?. Canadian Journal of Zoology. 69(9). 2423–2429. 121 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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