Charles Darwin and Alfred Wallace were both British naturalists from the 1800s; they independently investigated the phenomenon, which is now called natural selection. While Charles Darwin was the more well-known proponent of the theory of evolution by natural selection as he was the first to collect data for the idea, Alfred Wallace was a junior who had almost simultaneously theorized about the transmutation of species as a reaction to environmental factors. As Darwin was already an established naturalist at the time, Wallace sent his paper detailing his ideas to the famous scientist while Darwin was still gathering more evidence for his book on the topic. The essay was entitled On the Tendency of Varieties to Depart Indefinitely From the Original Type.
Having already shared his thoughts on natural selection with his naturalist colleagues, Darwin was advised by Joseph Hooker and Charles Lyell on how to deal with the similarities between both scientists’ discoveries. They decided that both should be acknowledged for their groundbreaking findings. Wallace’s essay, as well as portions of Darwin’s writings regarding the divergence of species, were read on July 1, 1858, at the Linnean Society of London. All acknowledged that Darwin formulated the theory first, and Wallace was credited as a co-discoverer. Darwin and Wallace released books on Natural Selection; the former published On the Origin of Species in 1859, while the latter released Darwinism in 1889. Their relationship as fellow scientists was a friendly one despite speculation by the journalist Arnold Brackman and the evolutionary biologist John Langdon Brooks that Darwin stole part of his theory from Wallace’s paper.
Charles Darwin’s Discovery
Charles Robert Darwin was born on February 12, 1809, to a wealthy doctor named Robert Darwin and his wife, Susannah Wedgwood Darwin. His upper-class status in society allowed him to pursue varied kinds of study as advised by his father, who wanted him to become either a physician or a clergyman. Additionally, his grandfather, Erasmus Darwin, constructed one of the pioneering theories on evolution called Zoonomia, which he wrote about in his poetic essay entitled The Temple of Nature.
Robert Darwin’s influence on his son prompted Charles Darwin to attend medical school at the University of Edinburgh, where he learned taxidermy, a skill that would be useful in his search for the origin of species. After neglecting his medical studies, Darwin was sent by his father to Christ’s College, Cambridge, to become a clergyman. There he would be interested in William Paley’s Natural Theology which was the ruling school of thought regarding the origin of life on earth. Paley was a clergyman and utilitarian who proposed that the world was created by a divine entity who specifically designed the world to be as it is. This was the belief system that Darwin was accustomed to when he went on the 5-year H.M.S. Beagle expedition with captain Robert FitzRoy. His job was to collect artifacts, fossils, preserved animals, and plants as a naturalist aboard the ship. The group gathered samples and information from the coastline of South America.
Upon Darwin’s arrival back in the United Kingdom in 1836, he looked at the data he collected and read several sources that formed the theory of evolution by natural selection. His father funded his research which allowed him to meet several established naturalists, such as the geologist Charles Lyell. Lyell discovered that the earth’s surface changed over long periods. Other key persons in Darwin’s research were the paleontologist Richard Owen and the ornithologist John Gould. Gould, in particular, helped Darwin understand the divergence between the forms of the finches and the mockingbirds that he found on the different Galapagos islands. They were not variations of finches but rather different species of finches altogether. Gould also told Darwin that he mistook one of the finches for a wren.
In 1837 Darwin spent much of his time with his brother, named Erasmus after their grandfather. Of Erasmus’ group of friends was the social theorist Harriet Martineau. Her engagement in Malthusian theory prompted Darwin to look into transmutation, a contrast to the prevalent belief in Natural Theology as forwarded by the clergyman William Paley. Gathering his information from his travels, Darwin wrote the volumes of Zoology of the Voyage of H.M.S. Beagle released from 1832 to 1836.
In 1838, Darwin was consumed by reading Thomas Robert Malthus’ Essay on the Principles of Population, which composes the foundation of his future theory. Malthus proposed that restraint was needed for the population to survive because of the lack of resources; however, restraint was not present in the way that nature developed over time. Thus, Darwin came upon the realization that life on earth changed to survive and reproduce thus giving birth to different species. He called this process natural selection and formulated a graphic organizer that illustrated how one species stemmed into the different species he studied.
Darwin told his naturalist colleagues about his ideas, sending letters to Joseph Hooker and Charles Lyell. It was a shock to Darwin when in 1856 Alfred Wallace sent his paper from
Ternate city in the Maluku Islands. At this point, Wallace was still on his voyage in the Malay Archipelago.
Alfred Wallace’s Discovery
Alfred Russel Wallace was born the eighth child of Thomas Vere Wallace and Mary Anne Greenell Wallace. His father’s financial situation deteriorated during his childhood due to failed business ventures, resulting in Alfred’s withdrawal from schooling at the age of 14. He then moved to London to live with his older brother named John. There he listened to lectures at the London Mechanics Institute, where he learned to be open to radical political ideas. Then, he took an apprenticeship with his brother William and consequently moved to Kington, Herefordshire. Wallace did land surveying work from 1840 to 1843 which eventually led to a job at the Collegiate School in Leicester, where he taught students mapmaking and surveying. It was during this period that he studied Thomas Robert Malthus’ An Essay on the Principle of Population at the school library. He also met Henry Bates, the naturalist who noticed animals’ habit of mimicry. Bates influenced Wallace to gather and study different insects.
In 1845, William died, propelling Wallace back into surveying work. While Wallace worked with John on their architecture and civil engineering firm, he corresponded with Bates about Charles Lyell’s Principles of Geology and Charles Darwin’s H.M.S. Beagle journey. Wallace was inspired by Darwin’s voyage as a naturalist, and he too aimed to travel to collect animal specimens and fossils. He did so in 1848, joining Henry Bates on his expedition to Brazil on the Mischief.
Wallace was a supporter of radical scientific and political ideas, resulting in his search for evidence of transmutation. Unlike Darwin, who went on his trip with a possible bias towards naturalist theology, Wallace had already read Darwin’s paper and hypothesized about the divergence of species over increments of time.
The two naturalists went to the large city of Belém in Brazil and then to the Amazon Rainforest. They collected specimens from their different stops in South America. Their group added the botanist Richard Spruce and Wallace’s youngest brother, Herbert, to their party in 1849; however, Herbert died of yellow fever in 1851.
On July 12, 1852, Wallace traveled back to the United Kingdom. The ship called Helen burned down while they were at sea, leaving the explorer’s collection to sink. He only had some notes left to bring back to London. There he befriended British naturalists during his 18-month stay in the city.
Then, Wallace went back aboard a ship to the Malay Archipelago in 1854. The areas he traveled to are now Indonesia, Malaysia, and Singapore. He paid assistants from the islands to help him collect specimens, gathering over 125,000 pieces. Most were beetles. During his trip, Wallace wrote his paper On the Tendency of Varieties to Depart Indefinitely From the Original Type based on the different species he had encountered and documented while going to different islands. He sent this to Darwin for his opinion on the matter.
Darwin, with the advice of Hooker and Lyell, read Wallace’s paper alongside his writings about the phenomenon at the Linnean Society of London on July 1, 1858. Wallace was still on his voyage at the time and was informed of the arrangement after it took place. However, he was grateful to be acknowledged for his ideas because he was still an otherwise obscure naturalist at that point. Darwin’s name allowed for his thoughts on natural selection to be seriously considered by naturalist circles. After Darwin published On the Origin of Species in 1859, Wallace presented his findings in Darwinism in 1889.
Differences
While both Darwin and Wallace had similar thoughts on natural selection, there are some details upon which they did not agree. Darwin focused on the concept of “survival of the fittest,” believing that surviving and reproducing were the main goals of a species. Meanwhile, Wallace emphasized the idea that species adapted to their environments. This idea came into play similarly to Darwin’s theory, but Wallace placed less weight on the necessity of multiplying the population and rather on adjusting to environmental obstacles.