Carolus Linnaeus (1707-1778), Swedish naturalist, who developed binomial nomenclature to classify and organize plants and animals.

Linnaeus was born into a religious family in a small town in rural Småland. His father, a minister with a passion for plants, had a large garden through which he introduced his son to botany. Linnaeus became enamored with natural history and pursued this interest in every subsequent educational setting. In 1727 he entered the University of Lund to study medicine, largely because the training included materia medica (the study of botany). The following year, he studied in Uppsala because the university there had better botanical holdings and a large community of botanists. Linnaeus discovered problems in the systematic arrangement for botany and began to sketch his own classification method as early as 1730. By the time he left Sweden in 1735 to complete his medical education in Holland, Linnaeus's reputation as a botanist was secure.

In 1735, shortly after arriving in Holland, Linnaeus published Systema naturae, the first of several publications that presented his new taxonomic arrangement for the animal, plant, and mineral kingdoms. In 1738 he returned to Sweden, was appointed physician to the admiralty in 1739, and became the leading figure in the formation of the Swedish Academy of Science. In 1741 Linnaeus was appointed professor of practical medicine at Uppsala, a position he exchanged the following year for the chair of botany, dietetics, and materia medica. He remained in this position for the rest of his life, an arrangement that allowed him to pursue his botanical interests and his concern with classification.

In 1751 Linnaeus published Philosophia botanica, his most influential work. In it, he claimed that a natural system of classification could be derived from God's original, immutable creation of all species. He proved the sexual reproduction of plants, providing the modern names to most of the flowering parts of plants. Linnaeus also created a taxonomic scheme that relied only upon these sexual parts, using the stamen to determine the class and the pistil to determine the order. He also used his binomial nomenclature to name specific plants, selecting one name for the genus and one name for the species. This naming scheme replaced that of the genus name followed by an extensive description for the species. Current naming schemes use Linnaeus's binomial nomenclature, but classify species based on their evolutionary relationships, determined by genetics, biochemistry, and morphology.

Linnaeus also made enormous contributions to animal taxonomy. Unlike his classification system for plants, however, he used a variety of characteristics, including observations from the internal anatomy of animals, to create a classification system that was the most widely accepted system in the 19th century.

Linnaeus's botanical collection and library were purchased by English physician James Edward Smith after Linnaeus's son died in 1783. Smith founded the Linnean Society in London in 1788, which housed the original collection and from which Linnaeus's ideas spread. His taxonomic arrangement for the natural world became the best-accepted classification system, particularly in the English-speaking world, by the early 19th century.