EVOLUTION

The idea of evolution came to dominate many aspects of Western thought in the late nineteenth century. Although associated primarily with the theory of the evolution of life on earth presented by Charles Darwin (1809–1882), the general idea of a natural development through time was also applied in many other areas, including the history of the universe, of the earth, and of human society and culture. Evolution was generally assumed to be progressive: that is, to advance toward higher levels of organization, with the human species—and modern Western culture—as the goals toward which it was driven.

Evolutionism was controversial because it challenged the Biblical story of creation and implied that humans were merely improved animals, thereby threatening the traditional belief that humans are the direct creations of God, possessing immortal souls that will be judged by eternal moral values. Darwin's theory of natural selection drove home the destructive implications of this challenge by showing how the appearance of new species could come about through the interaction of apparently unplanned and essentially haphazard natural processes. It also implied that struggle and competition were natural and indeed necessary aspects of nature's activities. Late-twentieth-century studies of the "Darwinian revolution" suggest, however, that the radical implications that modern thinkers find in Darwin's theory were largely subverted at the time. Evolution became popular because it was seen as the motor of progress, and natural selection merely weeded out the system's less efficient products. The human race was still the goal of creation, but produced by the purposeful laws of nature rather than supernatural divine action.

evolution before darwin

Although Darwin's Origin of Species, published in 1859, is credited with converting the scientific world to evolutionism and sparking a major public debate on the topic, the idea had been in circulation for at least a century. Although at first seen as a radical theory, modern historians have shown that by the 1850s the idea was being transformed into something that the middle classes could find acceptable. Darwin merely precipitated a transformation that had already been building up behind the scenes.

In the early eighteenth century, it was still widely believed that the earth was created only a few thousand years prior, with Noah's flood being the only agent of geological change. But by the later decades of the century, geologists had begun to show that the earth had an extensive history far beyond that of the human race. In the early nineteenth century, anatomists such as Georges Cuvier (1769–1832) began to reconstruct the fossil bones of extinct species and developed the concept of a sequence of geological periods each with its own inhabitants. Initially, conservative naturalists interpreted this evidence in terms of a modified version of the old idea of divine creation. Instead of a single creation in the Garden of Eden, God formed a new collection of species at the beginning of each epoch of earth history.

Highly speculative theories of the natural origin of species had already been postulated in the late eighteenth century. In his Des époques de la nature (Epochs of nature) of 1778, the Comte de Buffon (1707–1788) had argued that related species had gradually diverged from a single prototype as separate populations adapted to new environments. But he thought that the original types had been formed by a process of spontaneous generation at certain points in the earth's history, a view shared by materialist philosophers. Something resembling the modern idea of evolution emerged in the writings of Erasmus Darwin (1731–1802, Charles Darwin's grandfather), whose Zoonomia of 1791–1794 contained a chapter expounding the view that the laws of nature have led to the progressive development of life from the simplest organisms to humanity over a vast period of time. Such ideas were developed further in France by Jean-Baptiste-Pierre-Antoine de Monet de Lamarck (1744–1829), who also stressed a particular mechanism of transformation that would later be known as Lamarckism. This was the inheritance of acquired characters: the ancestral giraffes reached up to eat the leaves of trees, and the longer necks they thus acquired were transmitted to their offspring.

Although conservative scientists scorned Lamarck, modern research has shown that there was a strong current of radical thought in the 1820s that took his ideas seriously. In 1844, an attempt was made to adapt the idea of progressive transmutation to middle class attitudes in the anonymously published Vestiges of the Natural History of Creation (written by Robert Chambers [1802–1871]). Chambers presented evolution as the unfolding of a divinely ordained plan, and he explicitly included the human species as the endproduct of the trend. Although Vestiges attracted much criticism, it gained the idea of evolution a hearing and thus shaped the way public opinion would respond to Darwin.

darwin and darwinism

Charles Darwin had gained wide experience as a naturalist, especially on his voyage around the world on HMS Beagle (1831–1836). Soon after his return to England, he began looking for a natural explanation of how isolated populations would adapt to their environment, eventually producing new species. His theory of natural selection postulated a struggle for existence driven by shortage of resources, as outlined in the theory of population pressure advanced by Thomas Robert Malthus (1766–1834). Since individual animals have slightly varying characters, the best adapted would survive and breed, while maladapted individuals would be weeded out. This is the process that philosopher Herbert Spencer (1820–1903) would call the "survival of the fittest"—which encouraged many of Darwin's readers to assume that the "fittest" were the highest on a scale of progressive development, although Darwin had really focused on varying degrees of adaptation to the local environment.

When the Origin of Species was eventually published in 1859, there was renewed debate. Natural selection did not seem like the kind of mechanism a benevolent God would employ. Darwin published his views on human origins in his Descent of Man (1871) and it became clear that he saw the human mind very much as a product of natural evolution, with huge implications for the traditional view of morality. Darwin's supporters, including the young naturalist Thomas Henry Huxley (1825–1895), ensured that his theory survived the attacks of religious conservatives, and by the 1870s the majority of scientists and educated people had begun to accept the basic idea of evolution. The enthusiasm was so great that the idea of progressive evolution was soon being applied to social issues, generating the movement known as "social Darwinism." Spencer was the philosopher of the evolutionary movement, applying the idea to the whole development of life and of human society and culture. Spencer stressed the role of progress, and for him natural selection was a negative process that merely weeded out the less successful products of progressive evolution. Spencer invoked Lamarckism to explain how new characters were formed, as did the leading German Darwinist, Ernst Heinrich Philipp August Haeckel (1834–1919).

later developments

Spencer linked Darwinism to the competitive ethos of free-enterprise capitalism, which made his views especially attractive in America. Haeckel preferred to concentrate on competition between nations and races, not between individuals, and by the end of the century this model was widely incorporated into the rhetoric of imperialism. Evolutionism thus became the foundation for a variety of radical and liberal ideologies in various countries. But precisely because evolutionism was identified with progress, liberal religious thinkers were also able to accommodate the theory by seeing progress toward humanity as the unfolding of a divine purpose.

Although various forms of social Darwinism remained popular, among scientists there was growing distrust of natural selection, leading to an "eclipse of Darwinism" in which Lamarckism and other non-Darwinian mechanisms were preferred. In the early twentieth century, the philosopher Henri-Louis Bergson's (1859–1941) idea of "creative evolution" became a popular alternative to Darwinian materialism, although in fact Bergson's image of nature struggling blindly upward was more in tune with the open-ended, haphazard model of evolution implied in Darwin's work. There was no preordained goal toward which nature was being drawn, as in the older forms of progressionism.

Bergson's ideas influenced many biologists and thus helped to encourage a less teleological image of evolution. But natural selection remained suspect, and in biology, the most powerful alternative to Darwinism was genetics, popularized after the "rediscovery" of the work of Gregor Johann Mendel (1822–1884) on heredity in 1900. Genetics postulated clearly defined unit-characters transmitted from parent to offspring and ruled out any Lamarckian influence from the environment. Such rigid models of heredity played an important role in providing scientific plausibility for Sir Francis Galton (1822–1911) and the eugenics movement's calls for the sterilization of the "unfit" members of society. Artificial selection would thus replace the survival of the fittest as the means by which the human race would be perfected.

Geneticists initially rejected natural selection, believing that new characters produced by sudden "mutations" could establish new species instantaneously. But their theory had undermined the plausibility of Lamarckism, and Darwinism itself stressed the determining role of heredity. By 1914 a few biologists were beginning to realize that natural selection might act to weed out the less well-adapted mutations within the population. The stage was set for the reconciliation of genetics and selectionism that would create modern Darwinism in the interwar years.

See alsoBergson, Henri; Darwin, Charles; Galton, Francis; Haeckel, Ernst Heinrich; Huxley, Thomas Henry; Lamarck, Jean-Baptiste; Mendel, Gregor; Spencer, Herbert.

bibliography

Bannister, Robert C. Social Darwinism: Science and Myth in Anglo-American Social Thought. Philadelphia, 1979.

Bowler, Peter J. Evolution: The History of an Idea. 3rd ed. Berkeley, Calif., 2003.

Browne, E. Janet. Charles Darwin: Voyaging. London, 1995.

——. Charles Darwin: The Power of Place. London, 2002.

Desmond, Adrian J. The Politics of Evolution: Morphology, Medicine and Reform in Radical London. Chicago, 1989.

Moore, James R. The Post-Darwinian Controversies: A Study of the Protestant Struggle to Come to Terms with Darwin in Britain and America, 1870–1900. Cambridge, U.K., 1979.

Secord, James A. Victorian Sensation: The Extraordinary Publication, Reception, and Secret Authorship of Vestiges of the Natural History of Creation. Chicago, 2000.

Peter J. Bowler