Gesner, Konrad von (1516-1565) (World of Earth Science)
German physician, zoologist, and naturalist
Konrad von Gesner, a dedicated physician by many accounts, somehow managed to produce approximately 90 manuscripts during his short life span. The topics of his publications were encyclopedic in scope and ranged from zoology to theology, mountains to medicines, and to many other subjects that struck his fancy. Of all his works, the one of most interest to geologists is Fossils, Gems, and Stones (the full Latin title of this work is De Rerum Fossilium, Lapid um et Gemmarum maxime, figuris et similitudinibus Liber: non solum Medicis, sed omnibus rerum Naturae ac Philogiae studiosis, utilis et juncundus futurus). It was published in the year of his death (1565).
Gesner's Fossils, Stones, and Gems is significant primarily for two contributions to the study of fossils, minerals, rocks, and gems. First, although he did not recognize fossils as the remains of once living things (he labeled them stony concretions), Gesner realized that their unusual appearance deserved recognition. Therefore, he assembled the first extensive collection of fossil illustrations. However, he was not the first to publish fossil illustrations, as some historians have suggested; German naturalist Christophorus Encelius (1517583) included illustrations of four fossils in a publication 14 years prior to Gesner's work. Gesner's illustrations went far beyond Encelius' work in scope and even included the four illustrations from Encelius' publication.
Second, like his contemporary, German scientist Georgius Agricola (1494555), Gesner recognized the inadequacy of past methods of classifying fossils, rocks, minerals, and gems which ranged from alphabetical listings to nonsensical mystical properties. Agricola solved the classification problem by carefully identifying physical and chemical properties of certain minerals, a methodology that remains in effect today. Gesner approached the classification problem from a very different perspective. He constructed a list of 15 classes into which he held that most fossils, rocks, minerals, and gems could be categorized.
To the modern geologist, some of these classes may seem trivial or illogical. In class three, for example, fossil Echinoderms, Neolithic stone axes, and minerals that have a smokey appearance are all grouped together as objects that fell from the sky. This class was derived from the teachings of the Greek philosopher Aristotle (38422 B.C.) and was believed to be the literal truth. Other classes appear to have little value. Class thirteen bears this out by including only fossils, rocks, minerals, and gems that derive their names from birds. A few of Gesner's classes, however, proved valuable to future fossil research. Despite the fact that neither Gesner nor his contemporaries recognized fossils as the remains of living things, he applied his remarkable knowledge of zoology to a practical classification of many fossils. Class 10 (coral in appearance), Class 11 (coral like sea plants in appearance), Class 14 (appearance of things living in the sea), and Class 15 (appearance of insects and serpents) all make this point.
It was not until 136 years after Gesner's death that English naturalist, John Ray (1628705), declared that fossils were the remains of ancient life and another hundred years before Ray's views were generally accepted. But it was Gesner's early illustrations and some of his methods of classification that highlighted the remarkable similarities between the fossil record and living organisms.
Historians have recorded that Konrad von Gesner refused to leave his patients when the plague struck Zürich, Switzerland in 1565. After contracting the disease himself, he asked to be carried to his study when he felt death was near. It was there, among his voluminous library and eclectic collections, that he died.
See also Fossil record; Fossils and fossilization