Regnier de Graaf
Regnier de Graaf
1641-1673
Dutch Anatomist
In his very short career, Regnier de Graaf contributed to knowledge of the pancreas and the female reproductive system. He became the first scientist to identify and describe the ovary, and discovered a structure within the latter known as the Graafian follicle.
De Graaf was born on July 30, 1641, in the Dutch town of Schoonhoven. During his academic career, he studied at a number of universities: Utrecht, Leiden, Paris, and Angers, where in 1665 he received his degree.
In 1664, de Graaf conducted the first of his important experiments—in this case, involving the pancreas. Using a fistula, a sort of tube, he figured out how to extract pancreatic juice from a living dog. As it turned out, however, the theory regarding pancreatic juice that he formed as a result of this experimentation was incorrect.
Four years later, in 1668, de Graaf began his studies in the reproductive system. He first examined the male system, but yielded no information that was not already known. With the female system, however, he identified the ovary, whose existence had earlier been posited by Johannes van Horne (1621-1670) and microscopist Jan Swammerdam (1637-1680).
Over the few years that followed for de Graaf, he dissected the ovaries of numerous animals and located the Graafian follicle. He even identified changes in the ovarian structure following fertilization, and witnessed the release of fertilized ova. The latter had yet to be identified by science, however—in fact it would be many years before scientists understood the function of the ovum—and thus de Graaf did not really understand what he was seeing.
De Graaf was only 32 years old when he died on August 21, 1673, a victim of the plague. In his lifetime and afterward, his independent research—notable in part because it was not done under the aegis of any university—attracted the admiration of other anatomists.
JUDSON KNIGHT