Ernst Haeckel

German biologist

• Born: February 16, 1834
• Birthplace: Potsdam, Prussia (now in Germany)
• Died: August 9, 1919
• Place of death: Jena, Germany

Haeckel classified many marine organisms, especially the radiolaria and the medusae. He is most noted for his refinement of Charles Darwin’s theory of evolution, its extension to humankind and the origin of life, the refinement of the biogenetic law, and the development of monism as a religion.

Early Life

Ernst Heinrich Philipp August Haeckel (HEHK-ehl) was the son of Karl and Charlotte Sethe Haeckel. Both his Haeckel and Sethe relatives contributed prominently to German history and intermarried on several occasions. In both families there were several prominent lawyers. Karl Haeckel was a state councillor. Shortly after Ernst was born, his family moved to Meresburg. There, he attended school until he was eighteen. As a boy he had a great love of nature, which was fostered by his mother. He collected and classified many plants as a youth; his father occasionally gave him words of encouragement. He had a strong sense of independence and individuality, and even as a youth he was a compulsive worker.

In 1852, Ernst entered the University of Jena to work with Matthias Schleiden, a codeveloper of the cell theory. Schleiden taught him how to combine his interests in botany and philosophy. Not long after entering Jena, however, he became ill and had to return to Berlin to stay with his parents. He entered the University of Würzburg in the fall of 1852 to work with the botanist Alexander Braun. His father’s persistence, however, made him turn his attention to medicine. While at Würzburg, he studied under Albert Kölliker, Franz Leydig, and Rudolf Virchow. At Würzburg, he developed an interest in embryology.

The philosophy at Würzburg, where learning through research was emphasized, was well suited for the young Haeckel. Natural phenomena were explained and studied through cause-and-effect relationships and allowed little opportunity for the intrusion of mysticism and the supernatural. These philosophies laid the foundation for Haeckel’s future work.

Life’s Work

During the summer of 1854, Haeckel had the opportunity to study comparative anatomy under Johannes Müller. Müller gave Haeckel permission to work in the museum. During that summer, Müller took the young Haeckel to sea, where he taught him how to study living marine organisms. Haeckel stayed the winter at Berlin and wrote his first essay under the great Müller. In the spring of 1885, Haeckel returned to Würzburg, where, under Kölliker’s influence, he earned a medical degree in 1857 with a zoological/anatomical emphasis rather than a strictly medical one. Although Haeckel earned a medical degree, he seldom practiced medicine. This resulted from the fact that he spent most of his time studying marine animals and saw patients only from 5:00 to 6:00 a.m. During his first year of practice, he saw only three patients.

In the winter of 1859-1860, Haeckel studied the radiolaria collected off Messina. This project laid the foundation for his interest and future work in zoology . By the spring of 1860, he had discovered 144 new species of radiolaria. His work at Messina culminated in the publication of Die Radiolarien (Report on the Radiolaria , 1887) in 1862. This work was one of his finest and most influential, and it established his position as a zoologist. After a fifteen-year hiatus, he again pursued the study of radiolaria and published the second, third, and fourth parts of Report on the Radiolaria from 1887 to 1888. He eventually classified more than thirty-five hundred species of radiolaria.

In March, 1861, he was appointed private teacher at the University of Jena, and in 1862 he was appointed extraordinary professor of zoology at the Zoological Museum. In 1865, he became a professor at Jena. In August, 1862, he married his cousin, Anna Sethe. Anna died two years later at the age of twenty-nine. Stricken with grief over the loss of his beloved wife, he became a hermit and a compulsive worker, often surviving on only three to four hours of sleep each day. In 1867, he married Agnes Huschke.

In May, 1860, Haeckel read Charles Darwin’s On the Origin of Species by Means of Natural Selection (1859). The book profoundly influenced Haeckel’s intellectual development, and he became Germany’s most devout supporter and popularizer of Darwinism. It has often been said that without Haeckel there would have been Darwin, but there would not have been Darwinism. Haeckel came to view evolution as the basis for the explanation of all nature.

Haeckel, whose faith was enfeebled by the study of comparative anatomy and physiology, was also profoundly influenced by his friend Johann Wolfgang von Goethe and became a believer in Goethe’s God of Nature. Haeckel no longer believed in a Creator, because Darwin’s theory permitted him to explain nature without divine influence. This enabled Haeckel to accept Darwinism better than Darwin. For Haeckel, it became possible to develop a philosophy of nature without having to interject God or a vital force. Haeckel’s support of Darwinism made him the target of attack by his German colleagues, many of whom were doubters of Darwinian ideas. Haeckel first revealed his belief in Darwinism in Report on the Radiolaria. He acknowledges that in the radiolaria there are several transitional forms that connect the various groups and that they form “a fairly continuous chain of related forms,” and he expresses his “belief in the mutability of species and the real genealogical relation of all organisms.”

In an address to the Scientific Congress of 1863, eight years before Darwin published The Descent of Man and Selection in Relation to Sex (1871), Haeckel said that humans must recognize their immediate ancestors in apelike mammals. He realized, however, that Darwin’s theory may not be perfect and may need refinement. He especially realized that it explained neither the origin of the first living organism nor how humans were connected to the genealogical tree. Haeckel thought that the first living organism was a single cell, a cell even more primitive than the eukaryotic cell. Not long afterward, the prokaryotic cell, a primitive cell without a nucleus, was described. After studying the brains and skulls of the primates, Haeckel produced a genealogical tree that showed the relationship of humans to the other primates and to lower animals.

During the mid-1860’s, Haeckel began to study the medusae, a study that culminated in the publication of Das System der Medusen (Report on the Deep-Sea Medusae , 1882) in 1879. The treatise was a detailed description of the medusae. During the later 1860’s, he studied the social aspects of the medusae.

Haeckel’s greatest achievement was his Generelle Morphologie der Organismen , published in 1866. The monograph is considered a landmark and one of the most important scientific works of the latter half of the nineteenth century. In Generelle Morphologie der Organismen, Haeckel clearly presented his reductionist philosophy. He reduced the cell to the laws of chemistry and physics, and through the influence of Darwin, raised the study of zoology to that of the physical sciences. He strengthened the laws of evolution, refined the biogenetic law, and presented a philosophy of life and a new story of its creation. In it, too, he described his early education as defective, perverse, and filled with errors. He lambasted the educational system that emphasized memory of dead material that interferes with normal intellectual development.

In Generelle Morphologie der Organismen, Haeckel presented two ideas, monism and the biogenetic law, which would occupy the rest of his life. The biogenetic law, which was originally proposed by Darwin, was refined and expanded by Haeckel. According to the biogenetic law, ontogeny recapitulates phylogeny, which means that during embryological development animals pass through developmental stages that represent adult stages from which the developing animal evolved. Haeckel viewed embryonic development of an individual animal as a brief and condensed recapitulation of its evolutionary history. Haeckel used the biogenetic law to strengthen his case for evolution. Although the law was eventually proved to be in error, it was accepted by many scientists and stimulated much discussion and research. In Generelle Morphologie der Organismen, he presented a genealogical tree with bacteria and single-celled organisms on the bottom. From the bacteria and single-celled organisms arose two branches: the animals and the plants.

In his search for a religion that did not rely on a vital force or a personal god, Haeckel developed monism, a scientific and philosophical doctrine that advocated nature as a substitute for religion. The basic principles of monism can be summarized as follows: Knowledge of the world is based on scientific knowledge acquired through human reason; the world is one great whole ruled by fixed laws; there is no vital force that controls the laws of nature; living organisms have developed by evolution through descent; nothing in the universe was created by a Creator; living organisms originated from nonliving matter; humans and the apes are closely related and evolved from a common ancestor; God as a supreme being does not exist; and God is nature.

These outspoken and heretical ideas about God made Haeckel the target of attacks not only from the Church but also from his colleagues. Indeed, many of his colleagues called for his resignation as a professor, yet he stayed at Jena and raised it to the level of an intellectual metropolis. His reputation as a great scientist and thinker attracted many young, bright scientists to Jena.

Not being one to walk away from the battlefield and collapse under fire, Haeckel published Natürliche Schöpfungsgeschichte(The History of Creation , 1876) in 1868. This book was a condensation and a popularization on the ideas originally presented in Generelle Morphologie der Organismen and was written primarily for the layperson. In the book, Haeckel approached the problems of life through Darwinism. The book was attacked by theologians and by many scientists, but it became a best seller in its time.

The History of Creation was followed by Anthropogenie (1874; The Evolution of Man , 1879), a survey of all that was learned in the nineteenth century about the history of humankind, and Die Weltratsel (1899; The Riddle of the Universe at the Close of the Nineteenth Century , 1900), an intentionally provocative and popular study of monism that was translated into more than a dozen languages.

In his many popular writings, Haeckel unleashed a relentless attack on the Church and the clergy, which he thought preyed on the gullibility of the ignorant masses in order to further their selfish aims. He was criticized for being outspoken against established, organized religion while ignoring what his critics regarded as more serious ills of his country. He answered these charges in Die Lebenswunder (The Wonders of Life , 1904).

Haeckel founded the phyletic museum at the University of Jena and the Ernst Haeckel Haus to house his collections, books, and letters. He retired from active teaching and research in 1909 at the age of seventy-five and died at Jena in 1919.

Significance

Ernst Haeckel was one of the greatest natural historians, zoologists, and philosophers of the nineteenth century. His descriptions of many marine organisms, especially of the radiolaria and the medusae, were monumental and unparalleled in the zoological sciences. He classified several thousand new species of plants and animals.

Moreover, Haeckel’s knowledge of zoology provided him with a platform from which he launched an advocacy and popularization of the ideas of Darwin. He described evolution as “the most important advance that has been made in pure and applied science.” He was quick to extend and develop Darwin’s theory. He refined the biogenetic law and was one of the first to extend Darwin’s ideas to the origin of life and humankind.

Haeckel’s staunch support of Darwinism and his monistic philosophy alienated him from the clergy and from older scientists but attracted many younger scientists as disciples. Although he had many critics, more than five hundred university professors (many his critics) around the world contributed to the making of a marble bust of Haeckel, which was unveiled at the University of Jena in 1894. Haeckel’s ideas influenced a generation.

Bibliography

Bölsche, Wilhelm. Haeckel: His Life and Work. Translated by Joseph McCabe. London: T. F. Unwin, 1902. This is the most extensive biography of Haeckel, and the only one to have been translated into English. It is an excellent account of Haeckel’s work as a scientist and philosopher. Bölsche was one of Haeckel’s students.

De Grood, David H. Haeckel’s Theory of the Unity of Nature: A Monograph in the History of Philosophy. Boston: Christopher, 1965. Originally written as a master’s thesis, it was reprinted in 1982 by Gruner of Amsterdam. Summarizes Haeckel’s monistic philosophy.

Gasman, Daniel. Haeckel’s Monism and the Birth of Fascist Philosophy. New York: P. Lang, 1998. Examines monist philosophy and its role in encouraging the birth of fascist ideology in Italy and France.

‗‗‗‗‗‗‗. The Scientific Origins of National Socialism. New Brunswick, N.J.: Transaction, 2004. Traces the connections between Darwinism, Haeckel’s theory of monism, and other scientific ideas to Nazi racial doctrines.

Gould, Stephen Jay. “Abscheulich! (Atrocious!)” Natural History 109, no. 2 (March, 2000): 42. Describes the lives of Haeckel and two other scientists—Louis Agassiz and Karl Ernst von Baer—who became involved in the debate over Darwin’s theory of evolution. Explains the trio’s contributions to the debate.

Haeckel, Ernst. The Evolution of Man. Translated by Joseph McCabe. New York: G. P. Putnam’s Sons, 1905. The first edition to be translated into English.

‗‗‗‗‗‗‗. The Riddle of the Universe. Translated by Joseph McCabe. New York: Harper & Row, 1902. This book offers a popularization of Haeckel’s monistic philosophy “for thoughtful readers… who are united in an honest search for the truth.”

Hanken, James. “Beauty Beyond Belief.” Natural History 107, no. 10 (December, 1998/January, 1999): 56. Details Haeckel’s contributions and influence on evolutionary biology, including a discussion of his more controversial ideas.

Weikart, Richard. From Darwin to Hitler: Evolutionary Ethics, Eugenics, and Racism in Germany. New York: Palgrave Macmillan, 2004. Examines Darwin’s influence on German ethics and morality. Weikert explains how Haeckel and other German thinkers believed Darwin had overturned Judeo-Christian ethics. He describes how Haeckel exalted evolutionary fitness as the highest form of morality; this concept would become a central element in Nazi racial dogma.