Thursday, April 07, 2016

Two Amazing Men Discovered Evolution by Natural Selection!

Most everyone knows about Darwin, and what they think they know is that Charles Darwin is the discoverer of Evolution through Natural Selection. And for sure, he did discover this. But the amazing thing is....he wasn't the only one. And whereas Darwin came to this theory pretty much as a Big Data Scientist over a long period of time (mostly via "armchair" collection of data from scientists and naturalists around the world), The Other Guy developed his theory of Natural Selection very much in the field - more specifically, in the jungle, surrounded by the living evidence. 

His name is Alfred Russel Wallace, he is one of my heroes, and I offer below the "real story" for your reading pleasure. 

One of the things I really love about this story is the way Darwin and Wallace respected each other, and did right by each other. We all have a lot to learn from their integrity and compassion.

Alfred Russel Wallace and Natural Selection: the Real Story 
By Dr George Beccaloni, Director of the Wallace Correspondence Project, March 2013

http://downloads.bbc.co.uk/tv/junglehero/alfred-wallace-biography.pdf

Alfred Russel Wallace OM, LLD, DCL, FRS, FLS was born near Usk, Monmouthshire, England (now part of Wales) on January 8th, 1823. Serious family financial problems forced him to leave school aged only fourteen and a few months later he took a job as a trainee land surveyor with his elder brother William. This work involved extensive trekking through the English and Welsh countryside and it was then that his interest in natural history developed.

Whilst living in Neath, Wales, in 1845 Wallace read Robert Chambers' extremely popular and anonymously published book Vestiges of the Natural History of Creation and became fascinated by the controversial idea that living things had evolved from earlier forms. So interested in the subject did he become that he suggested to his close friend Henry Walter Bates that they travel to the Amazon to collect and study animals and plants, with the goal of understanding how evolutionary change takes place. They left for Brazil in April 1848, but although Wallace made many important discoveries during his four years in the Amazon Basin, he did not manage to solve the great ‘mystery of mysteries’ of how evolution works.

Wallace returned to England in October 1852, after surviving a disastrous shipwreck which destroyed all the thousands of natural history specimens he had painstakingly collected during the last two and most interesting years of his trip. Undaunted, in 1854 he set off on another expedition, this time to the Malay Archipelago (Singapore, Malaysia and Indonesia), where he would spend eight years travelling, collecting, writing, and thinking about evolution. He visited every important island in the archipelago and sent back 110,000 insects, 7,500 shells, 8,050 bird skins, and 410 mammal and reptile specimens, including probably more than five thousand species new to science.

In Sarawak, Borneo, in February 1855, Wallace produced one of the most important papers written about evolution up until that time1. In it he proposed a ‘law’ which stated that "Every species has come into existence coincident both in time and space with a pre-existing closely allied species". He described the affinities (relationships) between species as being “...as intricate as the twigs of a gnarled oak or the vascular system of the human body” with “...the stem and main branches being represented by extinct species...” and the “...vast mass of limbs and boughs and minute twigs and scattered leaves...” living species. The eminent geologist and creationist Charles Lyell was so struck by Wallace’s paper that in November 1855, soon after reading it, he began a ‘species notebook’ in which he started to contemplate the possibility of evolution for the first time.

In April 1856 Lyell visited Charles Darwin at Down House in Kent, and Darwin confided that for the past twenty years he had been secretly working on a theory (natural selection) which neatly explained how evolutionary change takes place. Not long afterwards, Lyell sent Darwin a letter urging him to publish before someone beat him to it (he probably had Wallace in mind), so in May 1856, Darwin, heeding this advice, began to write a ‘sketch’ of his ideas for publication.

Finding this unsatisfactory, Darwin abandoned it in about October 1856 and instead began working on an extensive book on the subject.

The idea of natural selection came to Wallace during an attack of fever whilst he was on a remote Indonesian island in February 1858 (it is unclear whether this epiphany happened on Ternate or neighbouring Gilolo (Halmahera)). As soon as he had sufficient strength, he wrote a detailed essay explaining his theory and sent it together with a covering letter to Darwin, who he knew from earlier correspondence, was deeply interested in the subject of species transmutation (as evolution was then called).

Wallace asked Darwin to pass the essay on to Lyell (who Wallace did not know), if Darwin thought it sufficiently novel and interesting. Darwin had mentioned in an earlier letter to Wallace that Lyell had found his 1855 paper noteworthy and Wallace must have thought that Lyell would be interested to learn about his new theory, since it neatly explained the ‘law’ which Wallace had proposed in that paper.

Darwin, having formulated natural selection years earlier, was horrified when he received Wallace’s essay and immediately wrote an anguished letter to Lyell asking for advice on what he should do. "I never saw a more striking coincidence. If Wallace had my M.S. sketch written out in 1842 he could not have made a better short abstract! ... So all my originality, whatever it may amount to, will be smashed." he exclaimed2. Lyell teamed up with another of Darwin's close friends, Joseph Hooker, and rather than attempting to seek Wallace's permission, they decided instead to present his essay plus two excerpts from Darwin’s writings on the subject (which had never been intended for publication3) to a meeting of the Linnean Society of London on July 1st 1858. The public presentation of Wallace's essay took place a mere 14 days after its arrival in England.

Darwin and Wallace's musings on natural selection were published in the Society’s journal in August that year under the title “On the Tendency of Species to Form Varieties; And On the Perpetuation of Varieties and Species by Natural Means of Selection”. Darwin's contributions were placed before Wallace's essay, thus emphasising his priority to the idea4. Hooker had sent Darwin the proofs to correct and had told him to make any alterations he wanted5, and although he made a large number of changes to the text he had written, he chose not to alter Lyell and Hooker’s arrangement of his and Wallace’s contributions.

Lyell and Hooker stated in their introduction to the Darwin-Wallace paper that “...both authors...[have]...unreservedly placed their papers in our hands...”, but this is patently untrue since Wallace had said nothing about publication in the covering letter he had sent to Darwin6. Wallace later grumbled that his essay “...was printed without my knowledge, and of course without any correction of proofs...”7

As a result of this ethically questionable episode8, Darwin stopped work on his big book on evolution and instead rushed to produce an ‘abstract’ of what he had written so far. This was published fifteen months later in November 1859 as On the Origin of Species: a book which Wallace later magnanimously remarked would “...live as long as the "Principia" of Newton.”9

In spite of the theory’s traumatic birth, Darwin and Wallace developed a genuine admiration and respect for one another. Wallace frequently stressed that Darwin had a stronger claim to the idea of natural selection, and he even named one of his most important books on the subject Darwinism! Wallace spent the rest of his long life explaining, developing and defending natural selection, as well as working on a very wide variety of other (sometimes controversial) subjects. He wrote more than 1000 articles and 22 books, including The Malay Archipelago and The Geographical Distribution of Animals. By the time of his death in 1913, he was one of the world's most famous people.

During Wallace’s lifetime the theory of natural selection was often referred to as the Darwin- Wallace theory and the highest possible honours were bestowed on him for his role as its co- discoverer. These include the Darwin–Wallace and Linnean Gold Medals of the Linnean Society of London; the Copley, Darwin and Royal Medals of the Royal Society (Britain's premier scientific body); and the Order of Merit (awarded by the ruling Monarch as the highest civilian honour of Great Britain). It was only in the 20th Century that Wallace’s star dimmed while Darwin’s burned ever more brightly. 

So why then did this happen?

The reason may be as follows: in the late 19th and early 20th centuries, natural selection as an explanation for evolutionary change became unpopular, with most biologists adopting alternative theories such as neo-Lamarckism, orthogenesis, or the mutation theory. It was only with the modern evolutionary synthesis of the 1930s and ’40s that it became widely accepted that natural selection is indeed the primary driving force of evolution. By then, however, the history of its discovery had largely been forgotten and many wrongly assumed that the idea had first been published in Darwin’s On the Origin of Species. Thanks to the so-called ‘Darwin Industry’ of recent decades, Darwin’s fame has increased exponentially, eclipsing the important contributions of his contemporaries, like Wallace. A more balanced, accurate and detailed history of the discovery of what has been referred to as “...arguably the most momentous idea ever to occur to a human mind” is long overdue.

ENDNOTES

1. Wallace, A. R. 1855. On the law which has regulated the introduction of new species. Annals and Magazine of Natural History, 16 (2nd series): 184-196.

2. Letter from Darwin to Charles Lyell dated 18th [June 1858] (Darwin Correspondence Database, http://www.darwinproject.ac.uk/entry-2285 accessed 20/01/2013).

3. These were an extract from Darwin’s unpublished essay on evolution of 1844, plus the enclosure from a letter dated 5th September 1857, which Darwin had written to the American botanist Asa Gray.

4. Publishing another person’s work without their agreement was as unacceptable then as it is today. Publishing someone’s novel theory without their consent, prefixed by material designed to give priority of the idea to someone else is ethically highly questionable: Wallace should have been consulted first! Fortunately for Darwin and his supporters, Wallace appeared to be pleased by what has been called the ‘delicate arrangement’.

5. In a letter from Joseph Hooker to Darwin dated 13th and 15th July 1858 (Darwin Correspondence Database, http://www.darwinproject.ac.uk/entry-2307 accessed 20/01/2013), Hooker stated " I send the proofs from Linnæan Socy— Make any alterations you please..."

6. In a letter from Darwin to Charles Lyell dated 18th [June 1858] (Darwin Correspondence Database, http://www.darwinproject.ac.uk/entry-2285 accessed 20/01/2013), Darwin, who was referring to Wallace's essay, says "Please return me the M.S. [manuscript] which he does not say he wishes me to publish..." and in a letter from Darwin to Charles Lyell dated [25th June 1858] (Darwin Correspondence Database, http://www.darwinproject.ac.uk/entry-2294 accessed 20/01/2013), Darwin states that "Wallace says nothing about publication..."

7. Letter from Wallace to A. B. Meyer dated 22nd November 1869 cited in Meyer, A. B. 1895. How was Wallace led to the discovery of natural selection? Nature, 52(1348): 415.

8. See Rachels, J. 1986. Darwin's moral lapse. National Forum: 22-24 (pdf available at http://www.jamesrachels.org/DML.pdf)

9. Letter from Wallace to George Silk dated 1st September 1860 (WCP373 in Beccaloni, G. W. (Ed.). 2012. Wallace Letters Online www.nhm.ac.uk/wallacelettersonline [accessed 20/01/2013])

OTHER NOTES

Please cite this article as: Beccaloni, G. W. 2013. Alfred Russel Wallace and Natural Selection: the Real Story. <http://downloads.bbc.co.uk/tv/junglehero/alfred-wallace-biography.pdf>
This article is a slightly modified version of the introduction by George Beccaloni to the following privately published book: Preston, T. (Ed.). 2013. The Letter from Ternate. UK: TimPress. 96 pp.