Carl Linné, better known to the scientific community by his Latinized name Carolus Linnaeus, is often called the Father of Taxonomy. His system for naming, ranking, and classifying organisms is still in wide use today (with many changes). His ideas on classification have influenced generations of biologists during and after his own lifetime, even those opposed to the philosophical and theological roots of his work.
You can check out his pages on arachnids over here: Goto Pages
He was born on May 23, 1707, at Stenbrohult, in the province of Småland in southern Sweden. His father, Nils Ingemarsson Linné, was both an avid gardener and a Lutheran priest, and Carl showed a deep love of plants and a fascination with their names from a very early age. Carl disappointed his parents by showing neither aptitude nor desire for the priesthood, but his family was somewhat consoled when Linné entered the University of Lund in 1727 to study medicine. A year later, he transferred to the University of Uppsala, the most prestigious university in Sweden. However, its medical facilities had been neglected and had fallen into disrepair. Most of Linné's time at Uppsala was spent collecting and studying plants, his true love. At the time, training in botany was part of the medical curriculum, for every doctor had to prepare and prescribe drugs derived from medicinal plants. Despite being in hard financial straits, Linnaeus mounted a botanical and ethnographical expedition to Lapland in 1731 (the portrait above shows Linnaeus as a young man, wearing the traditional Lapp costume). In 1734 he mounted another expedition to central Sweden.
He went to Holland in 1735, promptly finished his medical degree at the University of Harderwijk, and then enrolled in the University of Leiden for further studies. That same year, he published the first edition of his classification of living things, the Systema Naturae. During these years, he met or corresponded with Europe's greatest botanists, and continued to develop his classification scheme. Returning to Sweden in 1738, he practiced medicine and lectured in Stockholm before being awarded a professorship at Uppsala in 1741, where he restored the University's botanical garden (arranging the plants according to his system of classification) and inspired a generation of students with his love of botany. He continued to revise his Systema Naturae, which grew from a slim pamphlet to a multivolume work, as his concepts were modified and as more and more plant and animal specimens were sent to him from every corner of the globe. He still found time to practice medicine, eventually becoming personal physician to the Swedish royal family; in 1761 he was granted nobility, and became Carl von Linné. His later years were marked by increasing depression and pessimism; after a stroke, he died in 1778.
Perhaps the greatest observational biologist of his day, Linnaeus loved nature deeply, and always retained a sense of wonder at the world of living things. His religious beliefs led him to natural theology, a school of thought dating back to Biblical times but especially flourishing around 1700: since God has created the world, it is possible to understand God's wisdom by studying His creation. The study of nature would reveal the Divine Order of God's creation, and it was the naturalist's task to construct a "natural classification" that would reveal this Order in the universe.
However, Linnaeus's plant taxonomy was based solely on the number and arrangement of the reproductive organs; a plant's class was determined by its stamens (male organs), and its order by its pistils (female organs). "Plants" without obvious sex organs were classified in the "Cryptogamia," or "hidden marriage," which lumped together algae, lichens, fungi, mosses and other bryophytes, and ferns. Linnaeus freely admitted that this produced an "artificial classification," not a natural one, which would take into account all the similarities and differences between organisms. But like many naturalists of the time, in particular Erasmus Darwin, Linnaeus attached great significance to plant sexual reproduction, which had only recently been rediscovered. Linnaeus drew some rather astonishing parallels between plant sexuality and human love: he wrote in 1729 how
The flowers' leaves. . . serve as bridal beds which the Creator has so gloriously arranged, adorned with such noble bed curtains, and perfumed with so many soft scents that the bridegroom with his bride might there celebrate their nuptials with so much the greater solemnity. . .
Mostly because of its artificiality, but in part because of its explicit nature -- one opponent called it "loathsome harlotry" -- the specific details of Linnaeus's plant classification have largely been abandoned. Later systems of classification largely follow John Ray's practice of using morphological evidence from all parts of the organism in all stages of its development. What has survived of the Linnean system is its method of hierarchical classification and custom of binomial nomenclature.
For Linnaeus, species of organisms were real entities, which could be grouped into higher categories called genera (singular, genus). By itself, this was nothing new; since Aristotle, biologists had used the word genus for a group of similar organisms, and then sought to define the differentio specifica -- the specific difference of each type of organism. But opinion varied on how genera should be grouped; biologists often used arbitrary criteria to group organisms, placing all domestic animals or all water animals together. Part of Linnaeus' innovation was the grouping of genera into higher taxa that were also based on shared similarities. In Linnaeus's original system, genera were grouped into orders, orders into classes, and classes into kingdoms. Thus the kingdom Animalia contained the class Vertebrata, which contained the order Primates, which contained the genus Homo with the species sapiens -- humanity. Later biologists added additional ranks between these to express additional levels of similarity.
Before Linnaeus, species naming practices varied. Many biologists gave the species they described long, unwieldy Latin names, which could be altered at will; a scientist comparing two descriptions of species might not be able to tell which organisms were being referred to. For instance, the common wild briar rose was referred to by different botanists as Rosa sylvestris inodora seu canina and as Rosa sylvestris alba cum rubore, folio glabro. The need for a workable naming system was made even greater by the huge number of plants and animals that were being brought back to Europe from Asia, Africa, and the Americas. Linnaeus simplified naming immensely by designating one Latin name to designate the genus and one for the species -- the binomial ("two names"). For instance, in his two-volume work Species Plantarum (The Species of Plants), Linnaeus renamed the briar rose Rosa canina. This binomial system rapidly became the standard system for naming species. Zoological and most botanical taxonomic priority begin with Linnaeus: the oldest plant names accepted as valid today are those published in Species Plantarum, in 1753, while the oldest animal names are those in the tenth edition of Systema Naturae (1758), the first edition to use the binomial system consistently throughout. Although Linnaeus was not the first to use binomials, he was the first to use them consistently, and for this reason, names that naturalists used before Linnaeus are not usually considered valid under the rules of nomenclature.
In his early years, Linnaeus believed that the species was not only real, but unchangeable -- as he wrote, Unitas in omni specie ordinem ducit (The invariability of species is the condition for order [in nature]). But Linnaeus observed how different species of plant might hybridize, to create forms which looked like new species. He abandoned the concept that species were fixed and invariable, and suggested that some -- perhaps most -- species in a genus might have arisen after the creation of the world, through hybridization. Towards the end of his life, Linnaeus investigated what he thought were cases of crosses between genera, and suggested that, perhaps, new genera might also arise through hybridization.
Was Linnaeus an evolutionist? It is true that he abandoned his earlier belief in the fixity of species, and it is true that hybridization has produced new species of plants, and in some cases of animals. Yet to Linnaeus, the process of generating new species was not open-ended; whatever new species might have arisen from the primae speciei, the original species in the Garden of Eden, were still part of God's plan for creation, for they had always potentially been present. Linnaeus noticed the struggle for survival -- he once called Nature a "butcher's block" -- but considered it necessary to maintain the balance of nature, part of the Divine Order. The concept of open-ended evolution, not necessarily governed by a Divine Plan and with no predetermined goal, never occurred to Linnaeus; the idea would have shocked him. Nevertheless, Linnaeus's hierarchical classification and binomial nomenclature, much modified, have remained standard for over 200 years. His writings have been studied by every generation of naturalists, including Erasmus Darwin and Charles Darwin. The search for a "natural system" of classification is still going on -- except that what systematists try to discover and use as the basis of classification is now the evolutionary relationships of taxa.
Read more about Linnaeus and his classification in the dissertation of David Polly, a recent UC graduate in paleontology.
The Linné Herbarium, at the Swedish Museum of Natural History, preserves some of Linnaeus's original plant specimens. Persons who can read Swedish will find this Web page informative. You can also view Linnaeus's botanical garden -- along with other fine sights of the city of Uppsala -- courtesy of Uppsala University, Linnaeus's alma mater.
Founded a few years after Linnaeus's death, the Linnaean Society of London is still going strong as an international society for the study of natural history.
