Some time ago I wrote a blog where I highlighted the incredible contributions to science of Mary Anning, the poor, uneducated daughter of a cabinet maker in Lyme Regis through her discoveries of important fossils on what is now called the Jurassic Coast. Since then I have read two more books about her life, including “Remarkable Creatures” by Tracy Chevalier and “The Fossil Hunter” by Shelley Emling. The former is a novel, reconstructing the person that Mary Anning was, including potential romances. As such, this book is in part fictional. “The Fossil Hunter” is non-fictional, and apart from where the author speculates (which is fairly explicit) about what is likely to have occurred, this book really gives a wonderful insight into a remarkable individual who made highly significant contributions to our understanding of the evolution of life on earth, undoubtedly paving the way for the eventual acceptance of Charles Darwin’s “On the Origin of Species” .
Another person who contributed to Darwin’s masterpiece was Alfred Russel Wallace. In fact, without Wallace, “On the Origin of Species” would have looked significantly different, and it is questionable if it would have had as much of an impact as it did. Darwin’s plan was to publish a detailed, multi-part work. It was the realization that Wallace had come to the same conclusion that Darwin eventually decided to write the relatively short book that we now primarily associate with his genius.
This blog is based in large part on what I have learned from reading a wonderful biography of Wallace’s life by Ross A. Slotten titled “The Heretic in Darwin’s Court : The Life of Alfred Russel Wallace”. I grew up quite ignorant of Wallace, and I have to confess that he only emerged on my radar in association with the 200th anniversary of Darwin’s birth and the 150th anniversary of the publication of Darwin’s book in 2009. Reading Slotten’s book has opened my eyes to a brilliant but eccentric man, whose significance is thankfully once again recognized after years of obscurity. There is little question that Wallace was one of the great naturalists of the 19th Century. Like Mary Anning, and unlike the majority of scientists and naturalists in the 19th Century, Wallace spent much of his life in pursuit of financial stability. In other words, financial rewards were critical to allow him to pursue his passion for nature. This pushed him to become highly skilled as a naturalist and scientist, but also led him to some poor decisions, including poor investments and a wager against the Flat Earth Society (A topic that to my amazement is still being discussed!). Interestingly, Charles Darwin led a successful attempt to provide Wallace with a state pension, which provided basic financial support, but he financed most of his life through royalties from his writings.
Wallace had no academic credentials to his name, but was self-taught. His early excursions with Henry Walter Bates (of Batesian mimicry fame) eventually led to the first exploration trip for the two young men to the Amazon River. It was in the Amazon that he honed his skills as an explorer based on his keen ability of observation, including patterns of distribution. For example, he noticed that the distribution of many animal species was confined to one side or the other of the rivers, even when the distance across seemed relatively short. His training as a land surveyor undoubtedly contributed to this first foray into biogeography. The distribution of species became one of the themes of his work, and he is sometimes considered the father of biogeography. While Wallace made significant collections over the four years along the Amazon and its tributaries, his published accounts from the Amazon expedition, while impressive, were restricted by the fact that his journey to England came close to ending his life. His collections and almost all of his notes were destroyed when the brig Helen caught fire after only four weeks on the Atlantic. After a little more than a week in life boats, the crew was rescued by the merchant vessel the Jordeson. It took another 6 weeks to reach England, during which time the crew suffered rough weather and a shortage of provisions.
Wallace remained in England for a year and a half before setting out on his more famous journey to Southeast Asia and the Malay Archipelago, where he would remain for 8 years collecting birds and insects. Birds of Paradise were of particular interest to him, as they were to Europeans, so perhaps it was in part the premium remuneration he received for specimens of these remarkable birds that fueled that interest. It was here that his observations led him to the writing of several essays which were to change the course of scientific history. The first essay, “On the Law Which has Regulated the Introduction of New Species” generated little response from the scientific establishment. “On the Tendency of Varieties to Depart Indefinitely from the Original Type” was conceived and written over a few days while Wallace was suffering a severe malaria attack. He sent this essay to Charles Darwin for comment and to forward to the pre-eminent geologist of the day, Charles Lyell. To make a long story short, Wallace’s essay almost caused Darwin to abandon his work of 20 odd years, but he was convinced by Lyell, Thomas Huxley and Joseph Hooker convinced him to publish the shorter “On the Origin of Species” as we know it today.
After his return from the Malay Archipelago, Wallace was prominent in British science. Of particular interest was his relationship with Charles Darwin. Because of Darwin’s poor health the two rarely met, but they did correspond on a semiregular basis. One of the characteristics of Wallace was his humility, and he regularly downplayed his own role, referring to himself as “an amateur”. A passage in one of Darwin’s letters to Wallace is telling:
“Most persons in your position have felt bitter envy and jealousy. How nobly free you seem to be of this common failing of mankind. But you speak far too modestly of yourself; you would, if you had my leisure, have done the work just as well, perhaps better, than I have done it. “ (Slotten 2004, p. 173).
It is questionable if Wallace could have done what Darwin did. Darwin had spent several decades accumulating evidence for his theory through experimentation, including a thorough study of barnacles, and breeding of domestic pigeons. Wallace on the other hand was prone to theorizing, often speculating. Darwin was careful and measured, whereas Wallace often challenged dogmas, although he was a staunch defender of natural selection until his death in 1913. The two men agreed on natural selection as the key mechanism by which new species evolved, but they disagreed on many points. In particular, they disagreed on the function of sexual dimorphism and the function of colour within species. In addition, Wallace later in life believed that there was some intelligent driver and higher purpose of human evolution. What really disturbed the scientific establishment was his firm belief in Spiritualism, and he spent some time in the United States lecturing on natural selection and attending seances. To add insult to injury, Wallace was also a socialist, arguing for the rights of workers. It may have been his own humility along with a combination of issues like these that led to his gradual decline from the collective memory of evolutionary biologists.
Nevertheless, Wallace made huge contributions to science, and was amply rewarded. He received several honorary doctorates (Trinity College, Dublin, and Oxford), and declined several more (Cambridge and Wales), and he received the highest honours available at the time. At his death, there was a movement to have him buried at Westminster Abbey in London, where Charles Darwin was buried, but Wallace’s wife Annie followed her husband’s last wishes, and he was laid to rest in a small cemetery in Dorset.
Wallace’s research has left a lasting mark on science. In addition to numerous organisms named in his honour, several concepts remind us of him. One is the Wallace Line which is a faunal boundary between Wallacea (part of the Malay Archipelago) and Australia noted by Wallace in 1859. Another is the Wallace Effect which hypothesizes that natural selection can contribute to reproductive isolation.
This brief blog is obviously not nearly a complete reflection of this great man’s accomplishments. Slotten’s extensively researched book is 492 pages long in relatively small font, and I highly recommend it. In addition, there is of course a mountain of information on the web.