Eugen Warming and the Principles of Plant Ecology

The first textbook on plant ecology was published in 1895 in Copenhagen, Denmark, entitled Plantesamfund: Grundtræk af den økologiske Plantegeografi. It was translated into German in 1896 and again in 1902, into Polish in 1900, and into Russian in 1901 and again in 1903. It first appeared in English in 1909, published by the Clarendon Press, Oxford, England, with the title Oecology of Plants: An Introduction to the Study of Plant-Communities. The book was based on the lectures that provided the framework for the world’s first university course in plant ecology. The teacher and author of the textbook was Professor Eugenius (usually called Eugen) Warming (1841–1924) of the University of Copenhagen, a gifted and popular teacher whose ideas quickly became influential, despite the fact that he wrote in Danish, a language few foreign scientists could read.

Warming’s course and his book introduced all of the world’s major biomes—the largest biological units recognized, covering large areas and coinciding approximately with climatic regions. While describing the biomes, Warming explained how they developed. He showed that biological communities tended to solve particular environmental problems in similar ways, so that similar environments usually produced similar communities. These communities might consist of entirely different and only distantly related species, but they survived despite their differences because they had adapted to the conditions in which they lived. Cacti, for instance, are adapted to arid conditions, and they occur naturally only in the Americas. Their Old World equivalents, found in African deserts, are euphorbias, some of which are so similar to cacti that the two can be difficult to tell apart. Sidewinding, a method of locomotion that allows a snake to move across loose sand, is often associated with the American sidewinder (Crotalus cerastes), which is a species of rattlesnake. But at least three species of snakes that inhabit Old World deserts also employ sidewinding. Warming never accepted Darwin’s theory of evolution by natural selection, however. A strong believer in adaptation, he believed that new species emerged through offspring inheriting characteristics their parents had acquired during their lifetime by adapting to local conditions. This was the theory, now rejected by biologists, that Lamarck had proposed.

Johannes Eugenius Bülow Warming was born on November 3, 1841, on the Danish island of Mandø, where his father, Jens Warming (1797–1844), was the minister. His mother was Anna Marie von Bülow af Plüskow (1801–63). Following his father’s death, Warming and his mother moved to Vejle, in Jutland. Warming attended the cathedral school in the town of Ribe, and in 1859 he began to study natural history at the University of Copenhagen. He interrupted his studies from 1863 to 1866 to work as a secretary to the Danish paleontologist Peter Wilhelm Lund (1801–80) in the tropical grasslands of Brazil. Warming obtained his doctorate in 1871 from the University of Copenhagen. He was a lecturer in botany at the university from 1873 to 1882, when he was appointed professor of botany at the Royal Institution, Stockholm, Sweden. He held this post until 1885.

From 1886 to 1911, Warming held the position of professor of botany and director of the botanical gardens at the University of Copenhagen, but he was absent from Denmark from 1890 to 1892, engaged in fieldwork in Venezuela and the West Indies; in earlier years fieldwork took him to Greenland, Norway, and the Faroe Islands. He was rector of the university from 1907 to 1908. After his retirement, his successor as professor of botany was Christen Raunkiær.

Warming received many honors. He was a member of the Royal Danish Academy of Sciences and Letters from 1878 and an honorary fellow of the Royal Society of London. Warming married Johanne Margrethe Jespersen (1850–1922) in 1871. They had eight children. Eugenius Warming died in Copenhagen on April 2, 1924.