Between 1890 and 1892, Per Karl Hjalmar Dusén collected nearly 560 leaf fossils preserved in basalt near Mount Cameroon. A Swedish civil engineer by training, he expanded his professional reach into botany, paleontology, and cartography. Throughout his career, he conducted systematic scientific expeditions across diverse terrains in Greenland, South America, and West Africa.
Botanical and Scientific Expeditions
Dusén applied his technical background as an engineer to the rigorous demands of scientific exploration. His fieldwork focused heavily on documenting biological diversity, with specific expertise in pteridology, paleobotany, and bryology. His expeditions reached remote regions including Greenland, where he catalogued flowering plants, ferns, and horsetails on Disko Island. He furthered his research in South America and Cameroon, where he combined geological observation with extensive botanical collecting.
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Take the IQ test →Contribution to Paleobotany and Bryology
The fossils Dusén recovered from the coast of Cameroon provided significant data for the study of paleobotany. The German scientist Paul J. Menzel examined these 560 leaf specimens to analyze historical vegetation patterns. In the field of bryology, Dusén compiled and edited three exsiccatae collections, most notably 'Musci Africani in Camerunia a P. Dusén collecti' published in 1893, as well as 'Hepaticae Africanae in Camerunia a P. Dusén collectae'.
Legacy and Scientific Recognition
The scientific community acknowledged his contributions through extensive nomenclature and geographical naming. Over 200 species currently bear his name, including Acanthaceae specimens such as Acanthus dusenii and Justicia dusenii, as well as the lizard species Salvator duseni. In Greenland, Dusén Fjord serves as a permanent geographical marker of his explorations. His collected specimens remain archived at the New York Botanical Garden following the 1945 acquisition of the Princeton University herbarium.
Fast facts
- Born: 1855
- Died: 1926
- Nationality: Swedish
- Occupations: Paleontologist, cartographer, mechanical engineer, botanist
- Primary fieldwork regions: Brazil, Argentina, Kamerun, Greenland
- Major fossil collection: 560 leaf fossils from Cameroon
- Herbarium repository: New York Botanical Garden
Questions readers ask
What subjects did Per Karl Hjalmar Dusén study?
He specialized in botany with a focus on bryology, paleobotany, and pteridology, while also working as a civil engineer and cartographer.
Where are his botanical specimens housed today?
They are located at the New York Botanical Garden, which acquired them from the Princeton University herbarium in 1945.
Achievements
- Recorded as botanist, cartographer and scientific explorer
