The Origin of Species

Darwin’s Life

Charles Robert Darwin was born on February 12, 1809 in Shrewsbury, England. His parents, Robert Darwin and Susannah (Wedgewood) Darwin, were part of a group of well-known and wealthy society families. His father was a doctor, and his mother’s family was famous for its pottery business. In 1817, Darwin’s mother died. The next year, he began attending the Shrewsbury School as a boarding student. In 1825, he entered Edinburgh University to pursue a career in medicine, but he soon turned to the study of natural history. In 1827, he left Edinburgh for Christ College at Cambridge University, where he pursued a degree in theology. J. S. Henslow, a theologian and professor of botany, became one of Darwin’s close mentors. At Cambridge, Darwin also became familiar with the work of natural theologian William Paley. Paley’s influential book Natural Theology argues that observation of the natural world will lead to the conclusion that God is the “designer” of life.

After graduating from Cambridge in 1831, Darwin embarked on a five-year journey that would shape his career in natural history, and change his life. On Henslow’s recommendation, Captain Robert Fitzroy employed Darwin to accompany him on an expedition to South America and Africa. The trip provided Darwin with a unique opportunity to advance his career as a naturalist. Although Darwin suffered from seasickness and discomfort through much of the voyage on the H.M.S. Beagle, he was able to collect data and specimens that influenced his thinking on evolution and would later provide evidence for his evolutionary theory. It was also on this voyage that Darwin read Charles Lyell’s Principles of Geology, which turned out to be an important influence on his thoughts about geological change. The letters Darwin wrote and sent during the voyage were read before scientific societies and bolstered Darwin’s reputation in the scientific community. Upon returning to England in 1836, Darwin published Journal of Researches (1839), an account of his voyage.

In London, Darwin quickly became an eminent figure in the fields of natural history and botany. In 1837, his health declined, possibly as a result of a tropical disease he contracted in South America. In order to recuperate, he left London for the countryside, where he became acquainted with his cousin, Emma Wedgewood. Darwin made a list of the pros and cons of marriage, one of the pros being that a wife was “better than a dog”; after much consideration, he married Emma in 1839. They first settled in London before moving to the village of Down in Kent in 1842. They would have ten children, although three would die young and others would suffer from illnesses and aliments.

In Down, Darwin began preparing to publish his theory of natural selection. In 1844, he drafted a short essay about his theory. In 1847, he sent the essay to botanist Joseph Dalton Hooker for feedback. He also continued his work in other areas of natural science. His comprehensive study of barnacles, for example, won acclaim from biologists. However, Darwin’s health problems slowed his scientific research.

In 1858, while Darwin was working on the manuscript for The Origin of Species, he received an abstract of a theory of evolution from naturalist Alfred Russel Wallace, whose ideas sounded strikingly similar to Darwin’s. Darwin offered Wallace help in publishing the manuscript, but Hooker and Lyell, to whom Darwin had forwarded Wallace’s work, urged Darwin to finish his manuscript quickly so he could publish first. Some critics argue that Darwin stole ideas from Wallace. But because Darwin shared his research with Lyell and Hooker prior to receiving Wallace’s manuscript, and because Wallace’s theory was, in many ways, different from Darwin’s, the consensus is that Darwin did not plagiarize. Darwin rushed to finish the manuscript, and On the Origin of Species by Means of Natural Selection was published in 1859 (the title was shortened to The Origin of Species by Natural Selection after the first edition and today is commonly referred to as The Origin of Species).

Darwin’s theory received enormous public attention and generated both praise and controversy in the scientific realm and in the general public. The manuscript sold well and went through six editions in Darwin’s lifetime. Darwin devoted the rest of his career to publishing works further expounding his theory of evolution, such as The Variation of Animals and Plants Under Domestication (1868) and The Descent of Man (1871), which discusses humans in terms of evolutionary theory. Darwin died on April 19, 1882. In recognition of his contributions to science, he was given a state funeral and buried in Westminster Abbey.

Historical/Scientific Context

Although Charles Darwin is widely considered the founder of evolutionary theory, he was not the first person to propose that species evolved from one another. The theory that current life derived from previous life has existed in some form or another since ancient Greek times. Darwin’s grandfather, Erasmus Darwin, presented one of the first formal theories of evolution in his text Zoonomia (1794–1796). Some have argued that Darwin’s grandfather’s work inspired Darwin’s. However, it is widely agreed that Darwin’s theory was far more sophisticated than that of his grandfather, or of other evolutionary theorists.

Darwin’s evolutionary theory is representative of the eighteenth-century Enlightenment movement in Europe, which preached the superiority of empirical knowledge, rationality, and science over theological and religious reasoning. Enlightenment philosophy spurred a growth in scientific research in the eighteenth and nineteenth centuries, particularly in the biological and natural sciences. Classification of natural species became a primary task of naturalists. In Systema Naturae (1735), Carolus Linneaus outlined the modern system of species classification. Geologists also began studying the history of the earth’s surface. Charles Lyell’s Principles of Geology (1830–1833) argues that the earth operated on a “steady-state” system, maintaining its equilibrium through cyclical change as new matter replaces old matter. Lyell’s work was highly influential to Darwin, opening him to the idea that the natural world undergoes constant change over time. Groundbreaking work in mathematics and statistical knowledge at the time also had important applications for scientific inquiry into the natural world. Thomas Malthus’s Essay on the Principle of Population (1797) argued that exponential population growth would outpace the growth of food and resources, providing the basis for Darwin’s notions about the “struggle for existence.”

This growth of scientific research and reasoning inspired a number of naturalists to think about the origin of species. Prior to Darwin, several naturalists published theories of evolution. Darwin’s grandfather was one such naturalist. More famously, Jean-Baptiste Lamarck proposed a comprehensive theory of what he called transmutation in Philosophie Zoologique (1809). Lamarck argued that species evolved by creating their own adaptations to their environment and that these adaptations were inherited by their offspring. Lamarck theorized, for example, that the ancestors of giraffes stretched to reach food high in the trees, gradually elongating their necks over the course of generations. Later, Robert Chambers anonymously published Vestiges of Creation (1844), which conceived of the evolution of species as a linear progression from one to the next, but was vague about the mechanism that drove the evolution of species.

Most evolutionary theories came in for criticism from the scientific community. The fossil record failed to show evidence charting the evolution of current species from extinct forms. Biologists also lacked an understanding of the mechanisms of heredity—how, exactly, characteristics were passed from parents to offspring. It was unclear if or how “acquired characteristics” (such as giraffes’ stretched necks) were passed on to offspring. It was also unclear how variations occurred in species in the first place. Without a reasonable theory about a mechanism for variation, all proposed theories about mechanisms for species change (including Darwin’s natural selection) remained in doubt.

Besides these scientific criticisms, theology was a formidable obstacle to evolutionary theory. On its face, the idea that species evolved contradicted the biblical notion that God created species. Rather than challenging this biblical tradition, many naturalists attempted to reconcile their ideas with religious belief by suggesting that the natural world develops according to the intelligent design of a creator. William Paley attempted such a reconciliation in his famous work Natural Theology (1802). Evolutionary theory was also criticized for its materialist and haphazard worldview, according to which life develops and changes in reaction to random events, rather than in accordance with a divine plan. Darwin in particular was criticized for including humans in his theory of evolution, an inclusion that theologians argued ignored the intelligence and morality that separated humans from animals.

These criticisms prevented Darwin’s theory from gaining acceptance in the scientific community for many years. Interestingly, social theorists began applying Darwin’s theory to human society long before it gained scientific acceptance. Philosopher Herbert Spencer coined the term “survival of the fittest” in 1864 based on Darwin’s theory of natural selection, and Social Darwinists such as Spencer argued for laissez-faire government policies that would allow the dominant in society to prosper and the weak to die out, just as strong and weak species did in natural selection. Francis Galton, Darwin’s cousin, appropriated Darwin’s emphasis on heredity to promote the theory of eugenics, which proposed that the top members of society should birth more offspring, and the bottom members of society should be restricted in their reproduction, to ensure the evolution of a better human society. Eugenic theories have links to forced sterilization campaigns in the United States and the atrocities of Nazi Germany; while eugenic theorists may have found inspiration in Darwin, it is important to note that many of these theorists strayed far from his theories in their arguments.

In the twentieth century, the discovery of Mendelian genetics and genetic mutation provided the scientific basis for a resurgence of interest in Darwin’s theory in the scientific world. In 1900, biologists rediscovered Gregor Mendel’s 1860s experiments on pea pods, which provided the scientific basis for heredity missing from Darwin’s theory. Moreover, the discovery of genetic mutation by Hugo de Vries in 1903 and furthered by Thomas Hunt Morgan in 1915 explicated the mechanism for variation that could drive natural selection: Mutated genes could introduce new characteristics into populations that would then be passed on to offspring through heredity, providing a means for new species to be formed from old ones. Theodosious Dobzhansky synthesized these findings in genetics with natural selection in Genetics and the Origin of Species (1937), solidifying the validity of Darwin’s theory in the context of these new scientific understandings. Darwinism emerged as the leading explanation for evolution. Despite the objections of certain religious groups, Darwinism remains the scientifically accepted theory of the origin of species today.