The English biologist Thomas Henry Huxley (1825-1895) is most famous as "Darwin's bulldog," that is, as the man who led the fight for the acceptance of Darwin's theory of evolution.

On May 4, 1825, T. H. Huxley was born at Ealing, the seventh child of George and Rachel Withers Huxley. Perhaps because two brothers-in-law were doctors, Thomas decided to enter the medical profession and in the fashion of the time became an apprentice to a brother-in-law at the age of 15. In 1842 he won a free scholarship to the medical school attached to Chairing Cross Hospital in London and completed the course in 1846.

Huxley then sought a position in the medical service of the Royal Navy and was assigned to the Rattlesnake, a surveying ship bound for New Guinea and Australia. The Rattlesnake sailed on Dec. 3, 1846, and returned to England on Nov. 9, 1850. During two stopovers in Sydney, Australia, Huxley met Henrietta Heathorn, whom he married in 1855.

A Naturalist in Spite of Himself

Although another man held the post of naturalist on the expedition, Huxley found time amidst his duties as ship's surgeon to study those delicate marine animals that float near the surface of the sea. He worked up reports of his discoveries and sent them to England for publication. Those on the medusae, or jellyfish, were especially important and original. Soon after his return to England, and primarily on the basis of this work on the medusae, Huxley was elected a fellow of the Royal Society in 1851 and was awarded one of its royal medals in 1852.

Though still in his 20s, Huxley was now recognized as an accomplished investigator. But opportunities for a scientific career were rare in England, and from 1851 through 1853 Huxley sought in vain for a teaching position and for funds to cover the costs of publishing his complete researches. Finally, in 1854, he was appointed lecturer on natural history at the Government School of Mines in London. To supplement the meager income from this post, he was a year later named naturalist to the Geological Survey. This position carried with it certain duties with regard to fossils. Huxley accepted both positions with reservations. He "did not care for fossils" and "species work was a burden" to him. "There was," he wrote, "little of the genuine naturalist in me." What he hoped eventually to find was a position in physiology, but this was not to be. He spent all of his active career at the School of Mines and became a genuine naturalist in spite of himself.

In 1859 Huxley's monograph On the Oceanic Hydrozoa was published, but his research interests had expanded greatly by then. He ranged all over the field of zoology, but vertebrate morphology and paleontology had become his leading concerns. His most important single paper during this period was his Croonian lecture of 1858, "On the Theory of the Vertebrate Skull." In this work, as in that on the medusae and other marine animals, Huxley demonstrated the value of embryological development as a criterion for determining the significance of the anatomical features of adult animals.

Huxley and Evolution

Until Darwin published his theory of evolution, Huxley doubted that a transmutation of species had taken place. He considered the prior evidence for this idea insufficient, and he was unimpressed by previous attempts to provide a causal mechanism for evolution. Although Huxley was among the privileged few to hear the outlines of Darwin's theory in advance of publication, his active support for the theory seems to begin with the publication in November 1859 of the Origin of Species. Here at last was presented a mass of scientific evidence in favor of transmutation and, more importantly, a plausible mechanism as to how it had occurred--namely, by the "natural selection" of favored variations in the struggle for existence. "My reflection," Huxley wrote, "when I first made myself master of the central idea of Origin was 'How extremely stupid not to have thought of that!'" Even now he retained certain reservations about Darwin's theory, pointing out that no new species had been known to result from artificial selection and that Darwin had not given an adequate explanation of how variations are produced in the first place. Huxley suggested to Darwin that he had committed himself too exclusively to the notion of insensible gradations in variation; Huxley believed that variation might sometimes take place in larger and more clearly defined steps (what might today be called mutations).

But even with these reservations Huxley thought that Darwin's theory was a "well-founded working hypothesis" and a "powerful instrument of research." By comparison, the old doctrine that each species was an immutable special creation of God seemed "a barren virgin." Foreseeing that Darwin would be subjected to "considerable abuse" for his heresy, Huxley promised his less combative friend that he was "sharpening up my claws and beak in readiness." He was determined that Darwin's theory should receive a fair hearing, and he opened the campaign with a review appearing in the London Times the day after Christmas, 1859.

For his part in the open clash which resulted between science and the church, Huxley became a famous public figure. Neither among the public nor among scientists did Huxley ever really settle the question of the origin of species, but his fair and fearless advocacy of Darwin's theory did much to advance the cause.

Scientific Work

From 1860 to 1870 Huxley devoted himself largely to the question of man's origin and place in nature and to the study of paleontology. Along with W. H. Flower he produced apparently irrefutable evidence against Richard Owen's view that the brain of man possessed unique anatomical features. In Evidences as to Man's Place in Nature (1863) Huxley emphasized that the differences in the foot, hand, and brain between man and the higher apes were no greater than those between the higher and lower apes.

By 1871 Huxley had published 38 paleontological papers, including several on dinosaur fossils. Largely as a result of these papers and of more purely morphological work suggested by them, the evolutionary relationships between reptiles and the birds (the Sauropsida) and between amphibia and fishes (the Ichthyopsida) became more clearly understood. Huxley's work was also important in establishing the view that the Sauropsida and Mammalia had diverged from some common ancestor. Also during these years Huxley erected a new and largely successful classificatory scheme for the birds.

Administrator, Reformer, and Lecturer

Huxley was Fullerian professor of physiology at the Royal Institution (1856-1858), examiner in physiology and comparative anatomy for the University of London (1856-1863, 1865-1870); and Hunterian professor at the Royal College of Surgeons (1863-1870). Thereafter he devoted an increasing portion of his time to administrative and public duties.

Throughout his career Huxley published review articles and delivered a vast number of public lectures, both on scientific and more general topics. Gradually he acquired the lucid, forceful, and witty style for which he is so justly celebrated. Many consider him the greatest master of English prose of his time. His fervent belief that science should be diffused among the masses found expression in his famous lectures to working men, delivered from 1855 on.

Huxley's views on science, education, and philosophy gained an especially wide audience after he published Lay Sermons, Addresses and Reviews (1870). With regard to education in general, he insisted on the evils of one-sided education, whether classical or scientific, and on the need to cultivate the physical and moral as well as the intellectual capacities of children. But his main point was to chastise the English schools and universities for failing to recognize that science formed an essential part of Western culture.

In his philosophical essays Huxley placed himself in the tradition of "active skepticism" represented by René Descartes and David Hume. In essays like his famous "On the Physical Basis of Life" (1869) he insisted that life and even thought were at bottom molecular phenomena. For such ideas he was accused of being a materialist, but Huxley argued that "materialism and spiritualism are opposite poles of the same absurdity." To express his philosophical and theological position, Huxley in 1870 invented the word "agnostic." Because he thus denied that the existence of God could be proven, rejected the biblical account of creation and supported instead Darwin's theory of evolution, and tended toward liberalism or even radicalism in his political views, Huxley's name was anathema in respectable Anglican homes. But by his fair and courageous support of the truth as he saw it, he contributed greatly to an increased toleration toward free thought in Victorian England. In many ways Huxley is a mirror and a measure of his age.

In 1885 Huxley retired from all active duties and gave himself almost entirely to his philosophical and theological essays. He died at Eastbourne on June 29, 1895.

Further Reading

• The basic source on Huxley is Leonard Huxley, Life and Letters of Thomas Henry Huxley (1900). Although no adequate account of Huxley's scientific work exists, an attempt is made in P. Chalmers Mitchell, Thomas Henry Huxley: A Sketch of His Life and Work (1900). A work focusing on Huxley's role in education is Harold Cyril Bibby, T. H. Huxley: Scientist, Humanist and Educator (1959). Ronald W. Clark, The Huxleys (1968), is a popular, literate biography of Huxley and his famous grandsons Andrew, Julian, and Aldous Huxley.
• Autobiographies, Oxford Oxfordshire; New York: Oxford University Press, 1983.
• Clodd, Edward, Thomas Henry Huxley, New York: AMS Press, 1977.
• Di Gregorio, Mario A., T.H. Huxley's place in natural science, New Haven: Yale University Press, 1984.
• Huxley, Thomas Henry, Life and letters of Thomas Henry Huxley, New York: AMS Press, 1979, 1900.
• Huxley, Thomas Henry, The major prose of Thomas Henry Huxley, Athens: University of Georgia Press, 1997.
• Irvine, William, Apes, angels & Victorians: the story of Darwin, Huxley, and evolution, Lanham, MD: University Press of America, 1983, 1955.
• Jensen, J. Vernon (John Vernon), Thomas Henry Huxley: communicating for science, Newark: University of Delaware Press; London: Associated University Presses, 1991.
• Paradis, James G., T. H. Huxley: man's place in nature, Lincoln: University of Nebraska Press, 1978.
• Peterson, Houston, Huxley, prophet of science, New York: AMS Press, 1977.