Augustin Pyramus de Candolle
Augustin Pyramus de Candolle
Augustin de Candolle is considered one of the most important botanists of the nineteenth century. His major contributions were in the fields of plant classification and morphology, the study of form, and in the geographical distribution of plants.
Candolle was born in Geneva and his early studies were in Switzerland. In 1796 he moved to Paris, where he studied medicine and the natural sciences and where he often visited the natural history museum, which was a center for research. He came to know leading scientists of the day, including zoologist Georges Cuvier (1769-1832) and the early advocate of evolution, Jean-Baptiste de Lamarck (1744-1829). These connections increased Candolle's interest in biology to the point where he abandoned medicine and devoted himself to botany, focusing on the investigation of plant structure.
Candolle remained in Paris until 1808, when he was made chair of botany at the College of Medicine in Montpellier in southern France. From there, he moved back to Switzerland in 1816, when he became chair of natural history and director of the botanical garden at the Academy of Geneva. He retained these positions until 1835, when he retired and his son, Alphonse, also a noted botanist, took over his work. While at the Academy, Augustin Candolle created an impressive herbarium, a collection of dried plant specimens, that continues to be studied by botanists to this day.
The primary focus of Candolle's research was in taxonomy, a word that Candolle himself coined. It refers to the theoretical study of classification, of how organisms are sorted into categories. Candolle's work was influenced by that of the great French botanist, Antoine-Laurent de Jussieu (1748-1836). Both favored a natural system of classification as opposed to the artificial system of Carl Linnaeus (1707-1778), who had created the first widely accepted classification system. In this system a single feature, the structure of the flower, was used as the basis of classification. Plants with similar flowers would be placed in the same category even though they might differ greatly in other characteristics. A natural system, on the other hand, is based on decisions about overall similarity, with many characteristics being examined and considered.
Candolle was also influenced by the botanical work of the great German poet, Goethe (1749-1832), who was an enthusiastic student of botany. Goethe argued that there was a general plan or form that underlay all plant structure, with particular species being variations on this general theme. Candolle, too, saw unity underlying the diversity of plant form. He also agreed with Goethe that the parts of the flower were all related to the leaf form—that petals, for example, could be seen as modified leaves. This idea was very influential in the nineteenth century and reflected an interest in finding a way to simplify or unify the study of plants.
Candolle studied many plant families and wrote books on such plants as lilies and cacti. He also published several impressively illustrated works, including one with paintings by perhaps the most famous botanical illustrator of all time, Pierre Redouté (1759-1840). In terms of contributions to botany, Candolle's most significant work was called the Prodromus, which ultimately ran to 17 volumes, several of which were written and published after his death by his son Alphonse. This work was a description of the whole range of plants and attempted to include all known species. It presented information not only on classification but on ecology, agriculture, and phytogeography, which is the study of how climate and terrain influence the distribution of plant species. This last area is where Candolle made his most original contributions, and he is considered one of the founders of this field.
MAURA C. FLANNERY