Alfred Kahl

Alfred Detlef Fritz Kahl (18 February 1877 – November, 1946) was a German schoolteacher who took up microscopy in mid-life and became a leading authority on ciliated protozoa. In a burst of scientific productivity that lasted just nine years, he published 1800 pages of scholarly work, in which he described 17 new ciliate families, 57 genera, and about 700 previously unknown species. During his brief career as a protozoologist, he redescribed and illustrated nearly all the species of ciliates known in his time, and fit them into a taxonomic scheme that remains influential today.

Life

Kahl was born in the municipality of Warwerort, in the Dithmarschen district of Germany, a region of the country that includes the city of Hamburg. Official records show that he taught primary school in Hamburg, from 1897 to 1901, and that by 1934 he was teaching English, French and Natural History at a Gymnasium (High School) in Hamburg. Nothing else is known about his early life. His interest in ciliates began, according to his own account, when his daughter was studying under Eduard Reichenow, then head of the protozoa department at the Hamburg Tropical Institute: "The very interesting literature and preparations my daughter Lucia brought home fascinated me, as a dedicated biologist, and created the desire to study this field more deeply…Thus, I enthusiastically commenced literature reading and investigation of the small water bodies in my surroundings at the beginning of the year 1924. Within nine months, I got a rather solid knowledge in drawing and identifying many species." During his decade of activity, he nearly doubled the number of known ciliate species, and created a body of scholarship that is still cited with regularity. This accomplishment has been described by the ciliatologist John O. Corliss as an "unbelievable record [that] has never been--and is hardly ever likely to be--met in the annals of protozoology and microscopy, past, present, or future."

Selected publications

Kahl A. (1930–35) "Urtiere oder Protozoa I: Wimpertiere oder Ciliata (Infusoria)." In Die Tierwelt Deutschlands 18, (Ed. F. Dahl). G. Fischer, Jena. I. Allgemeiner Teil und Prostomata, 1930, p. 1-180 : Online lesen II. Holotricha (außer den im vol. 1), 1931, p. 181-398 : Online lesen III. Spirotricha, 1933 p. 399-650 : Online lesen IV. Peritricha and Chonotricha, 1935, p. 651-886 : Online lesen Kahl A. Untitled Monograph of 1943 (on Prostomatean ciliates). In Acta Protozoologica 2004 (Suppl.) 43: 11 - 69. Kahl's Keys to the Ciliates. (Ebook). English translation of the keys from Wimpertiere oder Ciliata, by David J. Patterson. 1978, University of Bristol.