Background

Georg Albrecht Klebs was born on October 23, 1857, in Neidenburg, Kingdom of Prussia (now in Poland). He was the third son of Emil Klebs, a Prussian Consistory Councillor.

Education

Klebs received his education in the small East Prussian city of Wehlau, entering elementary school in 1864 and graduating from the Realgymnasium in 1874. He then studied the natural sciences, philosophy, and art history at the University of Konigsberg. During his first semester he composed a prize essay in philosophy; but in preparing a study of the Desmidiaceae, an algae family, his interest was drawn to botany.

Career

Klebs served as an assistant to Anton de Bary at the University of Strasbourg (1878-1880). Subsequently, he became an assistant to the leading plant physiologists of the time, Julius von Sachs at Wurzburg and Wilhelm Pfeffer at Tubingen. In 1883 he qualified as a lecturer at Tubingen. Klebs was appointed a full professor at Basel in 1887 and obtained the same position in 1898 at Halle and in 1907 at Heidelberg, where he was simultaneously named privy councilor. Klebs was rector of the University of Basel for a year and twice dean of the Science and Mathematics Faculty at Heidelberg. Shortly before his death, he was elected rector of the University of Heidelberg.

Achievements

• Georg Albrecht Klebs is best remembered today as a master of developmental physiology. He not only presented interesting facts but also furnished, through suitable definitions, the correct points of departure for mastering developmental physiology through experimentation. Specifically, he was the first to make a logically consistent division of the influences affecting development into external conditions, internal conditions, and specific structure. Klebs demonstrated the validity of this point of view in many experiments on fungi, ferns, and flowering plants. Moreover, with this definition, he gave developmental physiology its own methodology and was thus its real founder.
  
  Klebs received a Croonian Lectureship in 1910. In 1913 he received the Knight’s Cross of the Zahringer Lowen.

Works

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  • Über künstliche Metamorphosen 1906
  • Über die Rhythmik in der Entwicklung der Pflanzen 1911
  • Die bedingungen der fortpflanzung bei einigen algen und pilzen 1896
  • Willkürliche Entwickelungsänderungen bei Pflanzen 1903
  • Ueber Die Fortpflanzungs-Physiologie Der Niederen Organismen, Der Protobionten 1896
  • Zur Entwickelungs-Physiologie Der Farnprothallien, Erster Teil, Dritter Teil, Zeiter Teil together with Uber Der Sporen Und Entwicklung Der Protonemen Einiger Moose 1917
  • Ueber Das Verhältniss Der Männlichen Und Weiblichen Geschlechts in Der Natur 1894
  • Ueber Einige Probleme der Physiologie der Fortpflanzung 1895

Views

In his scientific work, which was stimulated primarily by de Bary, Klebs at first concentrated on systematics among the algae and fungi, but he soon turned his attention to the cellular and reproductive physiology of these plants. His important discoveries in these areas include the fact that the presence of the nucleus is necessary for the formation of a cell wall.

Klebs’s principal work began with his extensive investigations of developmental variation among both lower and higher plants, particularly of the way in which variation is brought about through alteration of environmental factors. He defined their combined activity as follows: “All variations of a species are generated by the external environment in that it materializes, through its effect on the inner conditions, the powers lying dormant in the specific structure.” The crucial innovation of this conception is the distinction between the unchangeable specific structures (the genetic endowment) of the cell and the internal factors that are altered in response to external conditions.

Membership

Klebs was a member of many scientific academies, including the Heidelberg Academy for Sciences and Humanities and the Academy of Sciences of Turin.

Connections

On March 20, 1888, Klebs married Luise Charlotte von Sigwart of Tubingen; they had three children.

Father:

Emil Klebs

Spouse:

Luise Charlotte von Sigwart

colleague:

Julius von Sachs

colleague:

Heinrich Anton de Bary

colleague:

Wilhelm Pfeffer

References

• Dictionary of Scientific Biography, Volume 7
  1973