in supplementing the evidence adduced by Huxley in refutation of the skull-vertebrae theory: the theory of the origin of the skull from expanded vertebrae, which, formulated independently by Goethe and Oken, had been championed by Owen. Huxley demonstrated that the skull is built up of cartilaginous pieces; Gegenbaur showed that in the lowest (gristly) fishes, where hints of the original vertebrae might be most expected, the skull is an unsegmented gristly brain-box, and that in higher forms, the vertebral nature of the skull cannot be maintained, since many of the bones, notably those along the top of the skull, arise in the skin. In 1858, the physician Ernst Haeckel studied under Gegenbaur at Jena, receiving a doctorate in zoology (after his medical degree), and became a professor at the same institution, the University of Jena (see: Ernst Haeckel). Ernst Haeckel expanded on the ideas of Gegenbaur while advocating the concepts of Charles Darwin. In 1861, he published "Ueber den Bau und die Entwickelung der Wirbelthier-Eier mit partielleer Dotterbildung" ("Proof that the ovum is unicellular in all vertebrates", Arch. Anat. Phys., 1861.8: 461–529), a fundamental proof in embryology. Gegenbaur learned techniques as a student of Albert von Kölliker, Rudolf Virchow, Heinrich Müller and Franz Leydig (1821–1908). Karl Gegenbaur had a strong influence on his environment, with his colleagues Matthias Jakob Schleiden, Emil Huschke, Ernst Haeckel, and Hermann Klaatsch (1863–1916). Karl Gegenbaur also influenced his students, including: Max Fürbringer, Richard Hertwig, Oskar Hertwig, Emil Rosenberg, Ambrosius Hubrecht, Johan Erik Vesti Boas (1855–1935), Hans Friedrich Gadow, Georg Ruge M. Sagemehl, N. Goronowitsch, H. K. Corning, C. Röse and S. Paulli. Gegenbaur's research program of comparative morphology incorporating ontogeny and phylogeny is still evident in the burgeoning field of evolutionary developmental biology (evo-devo). Other publications Other publications by Karl Gegenbaur include a Text-book of Human Anatomy (Leipzig, 1883, new ed. 1903), the Epiglottis (1892) and Comparative Anatomy of the Vertebrates in relation to the Invertebrates (Leipzig, 2 vols., 1898–1901). In 1875, he founded the Morphologisches Jahrbuch ("Morphological Yearbook"), which he edited for many years. In 1901 he published a short autobiography under the title Erlebtes und Erstrebtes (German "experiencing and striving"). References Attribution Further reading External links 1826 births 1903 deaths 19th-century German zoologists Physicians from Würzburg People from the Kingdom of Bavaria Recipients of the Copley Medal University of Würzburg alumni Academic staff of the University of Würzburg Academic staff of the University