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Carolus Linnaeus
1707 - 1778

The Swedish naturalist Carl Linnaeus (1707-1778) established the binomial system of biological nomenclature, formalized biological classification, and gave the first organization to ecology.


Carl Linnaeus was born on May 23, 1707, in Rashult, the eldest of five children. Two years after his birth his father became the Lutheran minister at Stenbrohult. There young Carl had his own garden, which, he later remarked, "inflamed my soul with an unquenchable love of plants."

In 1716 Linnaeus went to the grammar school in nearby Växjö. He studied Latin, religion, mathematics, and science, but his interest in plants tended to interfere with his studies. A favorite book was Aristotle's Historia animalium, which his father had given him. His mother hoped he would enter the ministry, but he showed no interest in that career. Johan Rothman, a master at the high school, encouraged Linnaeus's interests in science and suggested that he study medicine. The father reluctantly agreed, and Rothman tutored Linnaeus in physiology and botany for a year.

In 1727 Linnaeus entered the University of Lund. The science and medical instruction was very weak, and after a year he transferred to Uppsala University, where he found that the two medical professors were old and seldom lectured. Fortunately, he soon attracted the interest of Olof Celsius, a theology professor who was interested in the plants of Sweden. Celsius gave him free room and board and became his mentor.

The most important contemporary development in botany was the study of the sexuality of plants. Linnaeus had learned of this discovery while at Växjö, but it was not generally known in Sweden. He wrote an essay on the subject, which Celsius showed to one of the professors of medicine, Olof Rudbeck. Rudbeck was so impressed with Linnaeus that he appointed him lecturer in botany and tutor of his sons.

His Travels

In 1732 Linnaeus received a grant from the Uppsala Scientific Society for a trip to Lapland. In 5 months he gained valuable knowledge of the Lapps and the natural resources of the country. The success of this trip led to invitations from the government at various times to make other trips to survey the resources of Sweden. On one of his journeys, through the province of Dalarna in 1734, he met Sara Lisa Moraea, to whom he became engaged.

Linnaeus needed a medical degree to become professionally established. At some European universities it could be earned by satisfactorily completing examinations and defending a thesis. In 1735 Linnaeus traveled to Holland, and after a week at the University of Harderwijk he took the examinations, defended his thesis on the cause of intermittent fever, and received his degree. He remained away from Sweden for 3 years, spending most of his time in Holland but also traveling in Germany, France, and England, meeting leading scientists as he went. He had brought with him a number of botanical manuscripts, and these won the admiration of the leading naturalists and the wealthy banker George Clifford.

These men provided Linnaeus with work and assisted in the publication of his manuscripts. The years in Holland were the most productive of his life: he published his Systema naturae, Bibliotheca botanica, Fundamenta botanica, Critica botanica, Flora Lapponica, Methodus sexualis, Genera plantarum, Classes plantarum, Hortus Cliffortianus, and lesser works. With understandable pride he concluded that in 3 years he had "written more, discovered more, and made a greater reform in botany than anybody before had done in an entire lifetime."

The Professor

Linnaeus returned to practice medicine in Stockholm. He was appointed physician to the Admiralty and soon had the best medical practice in Stockholm. In 1739 he married Sara Moraea; they had two sons and four daughters. Linnaeus became professor of botany at Uppsala University in 1741.

As a professor, Linnaeus was immensely successful. He had a genius for organization which he applied to both science and science education. His popularity with students was also based upon his attractive personality and his concern for their success. He taught botany, zoology, natural history, pharmacy, dietetics, and mineralogy. There were 186 students who defended these under his supervision. It was the custom for the adviser to write much, if not all, of the dissertation, and those which his students defended contained some of his important ideas in ecology and natural history. These theses were published separately and then collected into a periodical entitled Amoenitates academicae (1749-1790).

Linnaeus was not without detractors, some sincere, but many merely jealous. However, the love of his students and the value of his work ensured both his widespread influence and the receipt of many honors. He was appointed chief royal physician in 1747 and was knighted in 1758; he then took the name Carl von Linné. He retired in 1776 and was permitted to appoint as his successor his son Carl. Linnaeus died in Uppsala on Jan. 10, 1778.

Binomial Nomenclature and Classification

Linnaeus is most widely known for having introduced efficient procedures for naming and classifying plants and animals at a time when new species were being rapidly discovered by explorers. Before the insights of evolutionary theory provided a rationale for classification and nomenclature, the criteria used were arbitrarily chosen according to similarities in morphology, habitat, and man's uses of the species. In Linnaeus's day the problems of classification were most acutely felt in relation to flowering plants. Naturalists agreed that morphology was the most natural criterion, but in practice it was difficult to know which groups were most similar.

Linnaeus realized that new plants were being discovered faster than their morphological relationships could be established, and he decided to abandon for a while the attempt to achieve a natural classification. He devised a simple numerical classification based upon the number of floral parts. This system was so useful that it remained popular into the 19th century.

Gradually Linnaeus also developed a consistent system of names, in which each species of plant and animal had a genus name followed by a specific name: for example, Plantago virginica and Plantago lanceolata were the names of two species of plantain. Because he was the first to achieve a consistent and efficient system of nomenclature, botanists agreed in 1905 to accept his Species plantarum (2 vols., 1753) and zoologists agreed to accept the tenth edition of his Systema naturae (1758) as the official starting points for scientific names of plants and animals.

Ecology as the Economy of Nature

The subject of ecology as a distinct area of investigation was first outlined by Linnaeus in a thesis entitled Specimen academicum de oeconomia naturae, which was defended by one of his students in 1749. Linnaeus organized ecology around the balance of nature concept, which he named the "economy of nature." He emphasized the interrelationships in nature and was one of the first naturalists to describe food chains. He also studied plant succession, the diversity of habitat requirements among species, and the selective feeding habits of insects and hoofed animals. He was strongly interested in the distribution of species and studied their different means of dispersal. He urged the application of biological knowledge not only in medicine but also in agriculture, for he believed that the effective combating of agricultural pests must be based upon a thorough knowledge of their life histories.


Linnaeus, Carl (Carl von Linné; 1707–1778; ennobled 1761), Swedish naturalist and explorer. Linnaeus was born on 23 May 1707. His father was a curator in Råshult, a small parish in Småland (southern Sweden). After attending school in nearby Växjö, he studied medicine at the universities of Lund (1727) and Uppsala (1728–1732). Coming from a low-income family, he could only afford to attend a few lectures, but patronage from Olaus Rudbeck, Jr. (1660–1740) and Olof Celsius (1670–1756) at Uppsala University, and subsidies he received from teaching botany (1730–1732), allowed him to study natural history on his own. In 1732 the Uppsala Academy of Sciences sent Linnaeus to Lapland to do research. After his return, he gave private lectures in mineral assaying, and made another research trip to Dalecarlia (a region in central Sweden) in 1734. At this early stage, the foundation for all of his later work was laid down in manuscripts. Occasion for their publication would come when Linnaeus went to Holland in 1735 to acquire a medical degree. This journey was financed by the governor of Dalecarlia, the father of Sara Elisabeth Moraea, who was promised to Linnaeus.

Skillfully seeking the patronage of leading Dutch naturalists like Jan Fredrik Gronovius (1690–1762), senator of Leiden, and Herman Boerhaave (1668–1738), only a few months after his arrival Linnaeus successfully published his first work, the Systema Naturae (The system of nature), a folio volume of only eleven pages that presented a classification of the three kingdoms of nature. Success was immediate, and there followed a whole series of further publications, among them the Fundamenta Botanica (The foundations of botany, 1735) and the Genera Plantarum (Genera of plants, 1737). Linnaeus extended his stay in Holland until 1738 to catalog the extensive botanical collections of George Clifford, former director of the Dutch East India Company, who also paid him for two short trips to Paris and Oxford. On his return to Sweden in 1738, he married Sara Elisabeth and settled in Stockholm as a physician. He was among those who founded the Royal Academy of Sciences in 1739.

In 1741 Linnaeus accepted the chair of medicine and botany at Uppsala University. His career was characterized by two different aspects: On the one hand, he used the contacts he had made while in Holland to establish an international network of correspondents, including such leading naturalists as Albrecht von Haller (1708–1777) and Antoine-Laurent de Jussieu (1748–1836), that would supply him with seeds and specimens from all over the world. Incorporating this material into the botanical garden at Uppsala, Linnaeus created a continuously growing empirical basis for revised and enlarged editions of his major taxonomic works. There were twelve authorized editions of the Systema Naturae, as well as numerous pirated editions, translations, and popular versions that appeared in Europe.

On the other hand, Linnaeus actively supported the cameralist theory that a nation's welfare depended on science-based administration. He promoted the creation of chairs in economics at Swedish universities, organized public botanical excursions around Uppsala, undertook research travels within Sweden to identify domestic products that could replace imports, and sent some twenty students on travels around the globe to find exotic plants for acclimatization in Sweden. The results of these "patriotic" projects were published in the Flora Suecica (Swedish plants, 1745), the Fauna Suecica (Swedish animals, 1746), and four volumes of reports on journeys made to various provinces of Sweden (Öländska and Gothländska Resa, [Travel to Öland and Gotland], 1741, Västgötha Resa [Travel to Western Gothia], 1747, and Skånska Resa [Travel to Scania], 1751).

Linnaeus and his wife Sara Elisabeth, who managed the three farm estates of the family, had five children. His only son, Carolus, Jr., succeeded him at the University of Uppsala after his death in 1778, but died only a few years later.

The significance of Linnaeus's scientific achievements in natural history is twofold. His major taxonomic works, but especially the Species Plantarum (1753), a catalog of all plant species known at the time, provided systematic access to earlier literature in natural history, while the Philosophia Botanica (Philosophy of botany, 1751) laid down rules for classifying and naming organisms that would inform all future taxonomic practice. His main innovation in this respect was the introduction of binomial nomenclature, proposed for the first time in the Philosophia Botanica and for the first time consistently applied in the Species Plantarum. The latter work and zoological part of the tenth edition of the Systema Naturae (1756) form the basis of all subsequent botanical and zoological nomenclature, in conjunction with Linnaeus's extensive collections of botanical and zoological specimens, today preserved by the Linnaean Society in London.

Other fields in which Linnaeus is of historical importance include plant sexuality (Sponsalia Plantarum [The sex of plants], 1746), ecology (Oeconomia Naturae [The economy of nature], 1749), and the classification of diseases (Genera Morborum [Genera of diseases], 1763).











This web page was last updated on: 12 December, 2008