Biography of Carl Rabl
Carl Rabl made important contributions to morphology, comparative embryology, and developmental history. Most important, however, was his role in the development of the chromosome theory. Rabl first clealry expressed the concept of the continuity of the chromosomes throughout cellular division.
He was the son of Carl Rabl, a physician, and intended to study medicine. Already while attending the Gymnasium at Kremsmünster, he showed an interest in natural history and decided to study in Jena under the zoologist, physician, and evolutionist Ernst Heinrich Philipp August Haeckel (1834-1919), a famous advocate of Charles Darwin's theory of evolution.
However, instead of going to Jena, he first studied medicine for two years at Vienna from 1871. In the fall of 1873 he transferred to the University of Leipzig to work under the zoologist Karl Georg Friedrich Rudolph Leuckart (1823-1898). During the summers of 1874 and 1875 he studied in Jena under Haeckel, who influenced him strongly and became his friend and correspondent.
In 1875 came under the influence of another great teacher, the physiologist Ernst Brücke (1819-1892). While Haeckel was an enthusiast with a tendency to broad theorising, Brücke insisted on extremely careful observation in his histological studies and firmly placed fact before theory.
While a student under Haeckel, Rabl had begun investigations into the formation of the germ layers in the young embryo. This was soon followed up by research on the early cleavage and to the structure of the egg cell itself. This work convinced him that the events of cell division were precisely determined, and that embryological development was a mechanism in which the final position of each cell in the body had been predetermined,
In 1882 he eventually received his medical degree from the University of Vienna and subsequently became 1. prosector at the anatomical institute there, assisting Karl Langer (1819-1887). Rabl was habilitated for anatomy in 1883, becoming professor extraordinary in 1885.
At this time, Rabl concluded, following studies of salamander larvae, that the organisation of the cell must remain through division; that there was constancy in the number of chromosomal filaments characteristic of a given tissue; and that a numerical law applied to each kind of cell. The idea of the individuality of the chromosomes had first been suggested by the Belgian embryologist and cytologist Edouard van Beneden (1846-1910) and was given its fullest definition by Theodor Heinrich Boveri (1862-1915). Their works were fundamental to the understanding of the mechanism of heredity within the cell. The name chromosome was introduced by Heinrich Wilhelm Gottfried Waldeyer (1836-1921) in 1888.
Rabl continued this work when he, in 1885, was appointed teacher of anatomy at the Carl-Ferdinand-Universität in Prague (the German university in Prague). Here he attained the rank of ordinary professor in 1886 he. While at Prague, Rabl served a term as dean of his faculty, and he was rector of the Ferdinand University in 1903-1904. In 1891 he had married Marie Virchow, daughter of the pathologist Rudolf Virchow (1821-1902), However, although they had many friends and Rabl was esteemed by his colleagues in Prague, he felt that he would be happier at a German university and in 1904 accepted the chair at Leipzig as successor to Wilhelm His (1831-1904). Rabl directed the anatomical institute at Leipzig until his death in 1917.
Besides his work on the cell, Rabl’s numerous special investigations included the development of the heart in amphibians, the formation of the lens of the vertebrate eye, and cranial segmentation, skeletal derivation, and the origin of the paired extremities. His contributions to morphology were widely cited by other comparative anatomists. Carl Rabl was a nominee for the 1902 Nobel Prize for Physiology or Medicine. Another nominee was Hans Chiari (1851-1916). The prize was awarded Sir Ronald Ross (1857-1932) for his work on malaria.