Petrus Camper - Comparative Anatomy

Comparative Anatomy

One of the first scholar to study comparative anatomy, Petrus Camper demonstrated the principle of correlation in all organisms by the mechanical exercise he called a "metamorphosis". In his 1778 lecture, "On the Points of Similarity between the Human Species, Quadrupeds, Birds, and Fish; with Rules for Drawing, founded on this Similarity," he metamorphosed a horse into a human being, thus showing the similarity between all vertebrates. Étienne Geoffroy Saint-Hilaire (1772–1884) theorized this in 1795 as the "unity of organic composition," the influence of which is perceptible in all his subsequent writings; nature, he observed, presents us with only one plan of construction, the same in principle, but varied in its accessory parts. Camper's metamorphoses which demonstrated this "unity of Plan" greatly impressed Diderot and Goethe. In 1923 and 1939 some Dutch authors suggested that Camper foreshadowed Goethe's famous idea of "type" — a common structural pattern in some manner