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Johann Friedrich Theodor Müller

Born  1821-03-31
Died  18976-05-21

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    Usually referred to as Fritz Müller. Also called Müller-Desterro. German biologist and physician, born March 31, 1821, Windischholzhausen, Erfurt, Thuringia; died May 21, 1897, Blumenau, Brazil.

    Biography of Johann Friedrich Theodor Müller

    Article from Wikipedia:
    Fritz Müller was born in the village of Windischholzhausen, near Erfurt in Thüringen, Germany, the son of a minister. From 1841 to 1849 he received a scientific education at the universieties of Berlin and Greifswald, culminationg in a doctoral degree. He then decided to study medicine. As a medical student he began to question religion, and in 1846 became an atheist, joining the Free Congregations and supporting free love. Despite completing the course, he did not graduate because he refused to swear the graduation oath, which contained the phrase "so help me God and his sacred Gospel".

    Müller was disappointed by the failure of the Prussian Revolution in 1848, and spent the years 1849 to 1852 working in the countryside. and realised that there might be implications for his life and career. As a result, he emigrated to South Brazil in 1852, with his brother August and their wives, to join Hermann Blumenau's new colony in the State of Santa Catarina. The colony, near the coast on the Itajaí River, was called Blumenau. In Brazil, Müller, living with his wife Caroline, became a farmer, doctor, teacher and biologist, sometimes employed by the provincial government, sometimes surviving on his own efforts, sometimes defending against Indians but always collecting evidence of life in the Atlantic forest. The climate here is sub-tropical, and the vegetation typical of the Brazilian coast: it is not rain forest.

    Müller gained an official teaching post, and spent a decade teaching maths at a college in Desterro on the island of Santa Catarina. Then the college was taken over by the Jesuits, and Müller (though retaining his salary) returned to the Itajaí River valley. He negotiated a menu of botanical activities with the provincial government and spent the next nine years doing botanical research and advising farmers.

    In 1876 he was appointed as Travelling Naturalist to the National Museum in Rio de Janeiro. This was the ideal post for him: it gave him the opportunity to range over the whole of the Itajaí system and study anything that interested him. A series of reports published in the Archivos of the National Museum record this work. He was a contemporary of several other foreign naturalists who were invited to work there by the Director of the National Museum, Ladislau Netto (1838-1894), such as the Swiss-Brazilian naturalist and zoologist Émil Goeldi (1859-1917) and the German-Brazilian zoologist Hermann von Ihering (1850-1930).

    At last this, the best period of his life, was brought to an end indirectly, by the overthrow of the liberal monarchy of Dom Pedro II in 1889. The new Brazilian Republic was riddled with corruption and nepotism, and eventually there was a civil war in 1893–1895. One of the mistakes made by the Republic was to withdraw support from the regions, no doubt to make sure resources went to the new rulers and their families. Travelling naturalists were to be based in Rio de Janeiro, and instructions were sent out to the regions. Müller refused point-blank and was dismissed, as was von Ihering in São Paulo.

    In his retirement years Müller received many letters of support and offers of financial help (from Darwin, amongst others). His cousin Alfred Möller visited him, and eventually became his biographer. Alfred Möller was also a biologist, who researched fungi, and made a classic elucidation of the underground gardens of leaf-cutter ants.

    Müller and his wife had seven daughters and a son, who died early. His wife and several of the daughters also pre-deceased him; these losses affected him more than all the practical difficulties of life in Brazil. His rewards during life from the Brazilian state were minor; but his reputation now stands high. He was one of a half-dozen great naturalists to visit and work in South America during the nineteenth century. Humboldt, Darwin, Wallace, Bates, Spruce — and Fritz Müller. He was the only one of these to settle in Brazil for the rest of his life. A statue was erected to Müller in Blumenau in 1929.

    Müller became a strong supporter of Darwin. He wrote Für Darwin in 1864, arguing that Charles Darwin's theory of evolution by natural selection was correct, and that Brazilian crustaceans and their larvae could be affected by adaptations at any growth stage. This was translated into English by W.S. Dallas as Facts and Arguments for Darwin in 1869 (Darwin sponsored the translation and publication). If Müller had a weakness it was that his writing was much less readable than that of Darwin or Wallace; both the German and English editions are hard reading indeed, which has limited the appreciation of this significant book.

    Extensive correspondence exists between Müller and Darwin, and Müller also corresponded with Hermann Müller, Alexander Agassiz, Ernst Krause and Ernst Haeckel.

    During his life Müller published over 70 papers, mostly in German-language periodicals, some in English and Portuguese. The topics covered a range of natural history topics.

    In addition to the two phenomena named for him, one of Müller’s favourite topics was the life habits of the stingless honey-bees Melipona and Trigona. They are protected by a venom which they squirt when disturbed. The local name for them is Cagafogo (fire-shitter).

    Dimorphism in midges. Another discovery was the dimorphism in midges of the family Blephariceridae. There are two female forms with different mouth-parts: one sucks blood, the other takes nectar, as does the male. To prove the point to skeptics, he sexed the flies carefully, and reared them from pupae.

    Termites. By studying living termites Müller was able to correct many errors to be found in textbooks. For example, their caste system is organised quite differently from ants, since the castes contain members of both sexes, whereas in Hymenoptera the castes are unisexual and the males are haploid. Termites are placed in a completely distinct order from ants, traditionally the Isoptera.

    Botanical work

    Stimulated by Darwin, particularly his Fertilization of Orchids (1862), Müller made important contributions to botany. Darwin used some of his work in the second edition of 1877.


    Fritz Müller:

    Notes on some of the climbing-plants near Desterro in South Brazil.
    Journal of the Linnean Society. Botany, London, 1867, 9: 344-349.

    Über die Vortheile der Mimicry bei Schmetterlingen. Zoologischer Anzeiger, 1878, 1: 54–55.

    Aposematic colours Ituna and Thyridia: a remarkable case of mimicry in butterflies. 1879.
    Translated by R. Meldola. Proceedings of the Entomological Society of London, 1879: 20-29.

    On female dimorphism of Paltostoma torrentium.
    The Entomologists' Monthly Magazine, 1880/1881, 17: 225.

    On Fritz Müller and his work:

    Müller, Johann Friedrich Theodor. In “New International Encyclopedia. 1905

    Müller, Johann Friedrich Theodor. In “Encyclopedia Americana. 1920

    David A. West:
    Fritz Müller: a naturalist in Brazil. Blacksburg: Pocahontas Press, 2003.

    Alfred Möller (1860-1922):
    Fritz Müller. Werke, Briefe und Leben. Gsammelt und herausgegeben von Dr. Alfred Möller.
    Jena : G. Fischer, 1915.   [virtually the sole biographical source for this significant biologist]

    Cezar Zillig:   
    Dear Mr. Darwin. 1997. In Portuguese
    Letters between Müller and Darwin, with comments on the life of Fritz Müller.

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