Hans Spemann

German biologist

• Born: June 27, 1869; Stuttgart, Germany
• Died: September 9, 1941; Freiburg, Germany

In a career that spanned the late nineteenth and early twentieth century, German biologist Hans Spemann taught zoology and comparative anatomy for forty years and conducted influential research at several German universities. In the course of transplantation experiments, he was the first scientist to create a clone. Spemann received the Nobel Prize in Physiology or Medicine for his discovery of the principle of embryonic induction.

Primary field: Biology

Specialties: Zoology; anatomy

Early Life

Hans Spemann was born on June 27, 1869 in Stuttgart, Germany. The son of prominent publisher Johann Wilhelm Spemann and his wife Lisinka Hoffman Spemann, he was raised in a wealthy family. After graduating from the local gymnasium, Hans worked for his father for one year and served a mandatory year of military service. Spemann then enrolled in a medical studies program at the University of Heidelberg, where he worked with anatomist Karl Gegenbaur, who inspired his interest in zoology. After earning his bachelor’s degree in medicine in 1892, Spemann married Klara Binder. The couple had three sons and one daughter. Not long after his marriage, Spemann enrolled at the University of Munich for additional clinical training and laboratory work.

In 1894, Spemann relocated to the University of Würzburg to begin teaching zoology, where he took graduate courses at the university’s Zoological Institute under such professors as cytologist Theodor Boveri, physiologist and cell biologist Otto Bütschli, plant physiologist Julius Sachs, and physicist Wilhelm Röntgen, a Nobel laureate. In 1895, Spemann earned his PhD in anatomical studies with concentrations in zoology, botany, and physics. His dissertation focused on the cell lineage of nematodes. The following year, Spemann was stricken with tuberculosis.

Life’s Work

Following his recovery, Spemann returned with new purpose to Würzburg to continue his duties as a lecturer. Shortly after the turn of the century, he began a period of intense laboratory research and experimentation on the embryos of salamanders, newts, and frogs, concentrating on the division and transplantation of the cells of fertilized eggs. He published his first paper related to his studies in 1901.

In 1908, Spemann became professor of zoology and comparative anatomy at the University of Rostock, one of the oldest and largest institutions of higher education in northern Europe. He continued his work experimenting with amphibian embryos, investigating embryological induction in the development of particular tissues.

Between 1914 and 1919, Spemann served as chair of the department of experimental embryology and developmental mechanics at the Kaiser Wilhelm Institute (KWI) for Biology. From 1915 to 1918, Spemann served as codirector of the institute with geneticist Carl Correns.

In 1919, Spemann moved to Freiburg, a city on the French border. As a zoology professor at the University of Freiburg, Spemann set up a Department of Embryology (later renamed the Spemann Graduate School of Biology and Medicine). At Freiburg, Spemann and his colleagues and students carried out numerous experiments in transplantation. The department attracted many students who would become well-known scientists in Germany or abroad, including embryologist Viktor Hamburger and biologist Johannes Holtfreter.

Spemann’s doctoral student, Hilde Mangold, conducted work of particular importance. She carried out a series of experiments that Spemann designed, adroitly using microsurgery tools and techniques that Spemann pioneered. During 1921 and 1922, in support of her advanced degree, Mangold performed nearly five hundred transplanted grafts that demonstrated the “organizer effect” (later called embryonic induction), a key principle in the cell division of fertilized eggs. In 1924, Mangold and Spemann coauthored a paper entitled “Induction of Embryonic Primordia by Implantation of Organizers from Different Species.”

The paper served as the primary basis for the awarding of the 1935 Nobel Prize in Physiology or Medicine to Spemann. Mangold died of injuries she sustained after a gasoline heater in her home exploded. The Nobel Prize committee does not give awards posthumously, and Mangold was never formally recognized for her contributions, though Spemann always fully credited her important work in public and in his papers.

Spemann retired from his teaching work soon after winning the Nobel Prize, the first embryologist so honored. In 1938, he published a book—Embryonic Development and Induction—detailing his earlier experiments. The book also discusses an experiment involving the replacement of one egg nucleus with another nucleus, a concept that laid the foundation for nuclear-transfer cloning in the early 1950s. Spemann died in 1941 at age seventy-two.

Impact

Throughout his career, Spemann was preoccupied with the practical and theoretical aspects of experimental embryology, which was a brand-new field of research when he began his career in the late nineteenth century.

Much of Spemann’s work involved the manual division of the microscopic cells of fertilized eggs taken from such animals as newts, salamanders, and frogs in order to observe what happens when cells are split at various places and at different stages of development. To do so, Spemann had to invent the tools necessary to perform such experiments. He created needle-like knives from extruded glass to cut the embryos, and made miniscule pipettes to suck up fragments of cells. He also formed almost invisible glass rods with blunt ends to make small impressions in wax to hold embryos in place and built infinitesimal bridges made of glass to support delicate transplanted tissues. Always innovative, Spemann even used fine hairs from his infant daughter’s head to make tiny loops and nooses with which to divide cells.

Spemann spent his entire career exploring the subject of cell development and evolution. In the process, he established many of the principles and techniques of modern embryology and set the stage for the science of cloning.

Bibliography

Rheinberger, Hans-Jörg. An Epistemology of the Concrete: Twentieth-Century Histories of Life. Durham: Duke UP Books, 2010. Print. Examines the lives, work, and ultimate impact of twentieth-century experimental biologists and life scientists, including Spemann.

Shubin, Neil. Your Inner Fish: A Journey into the 3.5 Billion-Year History of the Human Body. New York: Vintage, 2009. Print. Illustrated work incorporating Spemann’s experiments in embryological development into an interesting discussion of animal evolution in general and human evolution in particular.

Slack, Jonathan M. W. Essential Developmental Biology. Hoboken: Wiley-Blackwell, 2005. Print. Explains the processes involved in the development of an embryo on molecular and cellular levels, from fertilization to maturity; contains many full-color drawings, a glossary, and a bibliography.