(b. Niederutzwyl, St. Gallen, Switzerland, 31 August 1809; d. Zurich, Switzerland, 27 September 1883)
Heer was the son of a Protestant minister who educated his son and prepared him for university study. As a boy and young man Heer collected plants and insects in the mountains near Matt, in the canton of Glarus, where the family moved in 1811, and he exchanged samples with other collectors. Following the family tradition, he began to study theology in 1828 at Halle and took his final examinations in this course at St. Gallen. Although deeply religious, he declined to become a minister.
While at the University of Halle, Heer had been in contact with professors of the natural sciences; and from 1828 he devoted himself completely to these sciences, undertaking in 1832 the examination and cataloging of a large, private insect collection in Zurich. This work led him to decide on a scientific career. He qualified in 1834 as a Privatdozent in botany at the newly founded University of Zurich and at the same time undertook the direction of the botanical gardens. He was named associate professor in 1835, and in 1852 he became full professor of botany and entomology. Beginning in 1855 he also taught taxonomic botany at the Technische Hochschule in Zurich. For almost fifty years Heer engaged in rich and fruitful teaching activity. His lectures treated taxonomic botany, pharmaceutical and economic botany, and, later, paleobotany and entomology—the latter dealt particularly with beetles and fossil insects.
In his youth Heer was a tireless traveler and an excellent mountain climber. In his fortieth year he contracted pulmonary tuberculosis, which occurred frequently in his mother’s family. Spending the winter of 1850–1851 on Madeira cured him for two decades, but in the winter of 1871 he became sick once again. This time he also suffered from a tubercular ailment of the leg, which put an end to all mountain excursions and confined him to his room every winter. He accepted his fate and continued to work until his death. He had remained unmarried. Heer’s biographers have emphasized his integrity, truthfulness, winning goodness, and gentleness. He constantly placed himself and his scientific knowledge at the service of the community. He gave popular lectures; founded, with the botanists K. W. von Naegeli and E. A. Regel, the Verein für Landwirtschaft und Gartenbau, of which he was president for eighteen years; wrote on the extermination of the cockchafer and on the economic situation of the canton of Glarus; and for eighteen years was a member of the canton council.
The principal areas of Heer’s research were paleobotany, plant geography, and entomology of living and fossil insects. His first major botanical work, on the vegetation of the canton of Glarus (1835), was the first monograph on plant geography of the Swiss Alps. Through its richness in new facts and ideas and through the precision with which the locations of the plants and their distribution in each high-altitude region were determined, this publication became a classic foundation for all later works of a similar nature. The same is true of Heer’s studies on the highest limits of animal and plant life in the Alps. The first publication on this subject appeared in 1845; at the end of his life he returned to it once more, on the broadest basis, in his study Über die nivale Flora der Schweiz (1883).
World fame first came to Heer for his paleobotanical investigations, especially of Tertiary flora. The titles alone indicate the remarkable range of his chief works in this area: Flora tertiaria Helvetiae (1855–1859), Flora fossilis Helvetiae (1876), and Flora fossilis arctica (1868–1883)—the last, according to Adolf Engler, the most important paleobotanical publication which had appeared until then. In these volumes 2,632 plant species are described, including 1,627 new species. Yet Heer never considered the increase in the number of fossil plant types as the main goal of his work. Rather, he constantly sought to synthesize the countless individual observations and facts into the evolution of the plant world and its environment, especially from the Tertiary to the present.
In the Flora fossilis arctica Heer described rich and varied Cretaceous and Tertiary floras from the north polar regions. This rich variety led him to maintain that the Arctic was a center of new formations from which plants radiated south to America, Europe, and Asia. These migrations of new plant species and groups, which originated in the Arctic and then became closely related “vicarious” species through simultaneous differentiation, explained in a simple manner the previously mysterious similarity of tree and shrub vegetation in two such distant regions as eastern Asia and Atlantic North America. In a similar way the theory could also account for the resemblance, already recognized by Heer, of the Tertiary flora of Europe and the recent flora of eastern Asia and Atlantic North America. While this “arcto-Tertiary” flora survived in the latter areas until the present, in Europe north of the Alps it was almost completely crowded out or destroyed during the Pleistocene. Only in the Mediterranean area and on the Canary and Madeira Islands in the Atlantic did remnants of this Tertiary flora survive.
In his investigations of the Tertiary flora Heer found that even in deposits of a similar geologic age the plant remains by no means always displayed the same composition; rather, localities in, for example, Greenland, Spitsbergen, and Italy showed decided differences. Hence in the Miocene the northern limit of palm trees lay in central Germany, where evergreen forests still existed, while in Iceland at the same period deciduous trees and conifers flourished, serving to indicate a cooler climate. This poleward organization of vegetation belts led Heer to postulate corresponding climatic zones during the Tertiary. He even attempted to determine the average yearly temperatures in the various zones from the climatic requirements of the living relatives of the Tertiary trees. He likewise confirmed by means of his paleobotanical findings the fact, already known from the study of the marine mollusks, that the temperature had gradually decreased in the course of the Tertiary.
Heer’s paleobotanical researches were not confined to the Tertiary. In Flora fossilis Helvetiae and Flora fossilis arctica, as well as in many articles, he described plant remains from the Carboniferous, Triassic, Jurassic, and Cretaceous periods and remarked on their paleobiogeographical and paleoclimatic significance. Heer also considered Pleistocene floras. For instance, he demonstrated by the discovery of Betula nana and other northern species of plants in Bovey Tracey, Devonshire, a cold glacial climate for southern England. From Pleistocene coal deposits at Dürnten and Wetzikon, Switzerland, he deduced a temperate interglacial climate for the Alps. And he found among the plant remains of the post-Ice Age Swiss lake dwellings connections with present-day cultivated plants.
As a child Heer had collected insects as well as plants and consequently was well acquainted with the close ecological relationships between the two groups of organisms. He published several works on the recent forms but increased knowledge of the world of fossil insects in a way that none of his predecessors or contemporaries had done. The chief locality he studied was Oeningen, on the Lake of Constance (southern Germany). From this Upper Miocene deposit, once a freshwater lake, he determined 826 insect species, with Coleoptera, Hymenoptera, Neuroptera (dragonfly larvae), and Hemiptera predominating. Simultaneously with Oeningen he worked at somewhat older Radoboj, in Croatia (1847–1853). He investigated the Lower Oligocene deposit at Aix-en-Provence in 1857. of special significance was Heer’s discovery of an insect fauna in the Lias at Schambelen in the canton of Aargau. In 1852 he described 143 species from this place and thus made a contribution that is still valuable to knowledge of the Mesozoic insect world.
As with fossil plants, recognition and classification of new species of fossil insects was not the ultimate goal of Heer’s studies. Starting from this necessary systematic-taxonomic base he attempted to reconstruct the natural conditions of existence of the prehistoric insects, their relationships to the surrounding plant world, and their organization into life communities while making a constant comparison with the conditions of life of the related recent species. Again Heer showed himself to be a master of paleoecology. As in his paleobotanical studies, there is a consideration of biogeography. Thus, in the Oligocene insect fauna of Aix-en-Provence he recognized a Mediterranean fauna with particular suggestions of North American, Indian, and Australian characteristics.
Heer was at the same time a botanist and a zoologist, a penetrating systematist with an enormous knowledge of forms; yet he was also a biologist who sought to grasp the richness of forms and the expressions of life of both the great kingdoms of nature as a harmonious whole. Evidence for this disposition is provided by his Urwelt der Schweiz, an extraordinarily vivid description of the geological history and the animal and plant world of Switzerland since the Paleozoic. For its union of scientific thoroughness and polished presentation, the book belongs among the classic works of this type. It appeared in two editions (1865, 1879), the first of which was translated into French and English.
In his paleontological researches Heer took issue with the theory of evolution, especially with Darwin’s ideas. He maintained that species in general were constant; nevertheless, at certain times in the history of the earth, during so-called periods of creation, species possessed the ability to bring forth resemblant species. Thus the present flora would have arisen from that of the Tertiary; the Sequoia langsdorffi would be the great-grandfather of the Sequoia sempervirens, the Liquidambar styracifluum would have originated from the Liquidambar europaeum, and so on; and, at an earlier time, the Tertiary flora would have developed from that of the Cretaceous. This whole plant world would thus have formed a great, harmonious totality in which all members stood in a genetic relationship.
Heer wrote this theory in 1855—four years before the appearance of Darwin’s Origin of Species—in a letter to his friend C. T. Gaudin. Although with these conceptions he came very close to Darwin’s theoretical ideas on descent, he decisively rejected the latter’s theory of selection. On the one hand, a theory of chance contradicted his religious belief in the existence of a plan for the world made by an omnipotent Creator; on the other hand, in his investigations of fossil plants he was never able to find the “gradual and ever regularly continuing, purposeless metamorphosis of species” presupposed by Darwin. Heer was inclined to accept a relatively sudden, erratic transformation of species.
I. Original Works. Heer’s writings include Beiträge zur Pflanzengeographie (Zurich, 1835), his diss.; “Die Insektenfauna der Tertiärgebilde von Oeningen und von Radoboj in Croatien,” in Neue Denkschriften der Allgemeinen schweizerischen Gesellschaft für die gesamten Naturwissenschaften, 8 (1847). 1–229: 11 (1850), 1–264; 13 (1853). 1–138; “Die Lias-Insel des Aargaus,” in Zwei geologische Vorträge... von O. H und A. Escher von der Linth (Zurich, 1852), pp. 1–5: Flora tertiaria Helvetiae, 3 vols. (Winterthur, 1855–1859); “Ueber die fossilen Insekten von Aix in der Provence,” in Vierteljahrsschrift der Naturforschenden Gesellschaft in Zurich, 2 (1857). 1–40: Die Urwelt der Schweiz (Zurich, 1865; 2nd ed., 1879), 1st ed. trans. into French as Le monde primitif de la Suisse (Geneva-Basel, 1872) and into English as The Primeval World of Switzerland (London, 1876); Flora fossilis arctica, 7 vols. (Zurich, 1868–1883); Flora fossilis Helvetiae (Zurich, 1876); and Ueber die nivale Flora der Schweiz (Zurich, 1883).
II. Secondary Literature. See J. Heer and C. Schröter et al., Oswald Heer: Lebensbild eines schweizerischen Naturforschers, 2 vols. (Zurich, 1887), with portrait; A. Jentzsch, “Gedächtnisrede auf Oswald Heer,” in Schriften der Physikalisch-ökonomischen Gesellschaft zu Königsberg, 25 (1885). 1–26, with complete bibliography, also in Leopoldina, 21 (1885). 18–20, 22–30, 42–49: K. Lambrecht and W. and A. Quenstedt, “Palaeontologi. Catalogus biobibliographicus,” in Fossilium catalogus, I, pt. 72 (The Hague, 1938), 194–195; R. Lauterborn, “Der Rhein. Naturgeschichte eines deutschen Stromes,” in Berichte der Naturforschenden Gesellschaft zu Freiburg im Breisgau, 33 (1934). 134 141; K. Mägdfrau, “Schneetälchen, Käfer und fossile Pflanzen,” in Heimat,67 (1959). 143–149 (with portrait); and G. Malloizel, Oswald Heer: Bibliographie et tables iconographiques; précédé d’une notice bibliographique par R. Zeiller (Stockholm, 1887), which contains a complete bibliography and list of the fossil animals, insects, and plants described and illustrated by Heer—references include page, plate, and figure number for each species.