Monday, 9 January 2017

Alfred Russel Wallace

January 8 is the birth anniversary of Alfred Russel Wallace. Last year, I was given an opportunity to write this essay for the online edition of New Indian Express by R Venkatasubramaniam. I share this now on my blog, partly named after him. 
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Charles Darwin and Theory of Evolution are famous. But how many know that Darwin was not the only person who discovered either evolution, or its primary mechanism, Natural Selection? How many know of Alfred Russel Wallace, one of the greatest biologists the world has known?

Most of us learn from textbooks in schools. But often, text books, especially on science, are dry collections of facts, which offer neither context nor history to great discoveries or adventures. It is the great failure of poets, novelists and filmmakers, that they rarely laud the accomplishments of great scientists or engineers, even though the world we live in has been dramatically modernized, modified and made a wonderful place because of their superhuman talents and efforts.

Wallace was as great a scientist as Newton and Darwin!
Wallace as a young man

Alfred Wallace was born in England, in a family that was poor but educated. His father died when he was seven. So he joined his elder brother William as an apprentice surveyor. While traversing the countryside surveying land, he was fascinated by plants and began collecting them. Darwin was already famous in England, because he had traveled around the world for five years in a British ship called HMS Beagle, studying biology, and had written a very popular book, “The Voyages of the Beagle.” Darwin himself had been inspired by the travels and adventures of Alexander von Humboldt, a German scientist. Humboldt’s book “Personal Narrative of a Journey to the Equinoctial Regions of the New Continent” caused a sensation in Europe.

In India, even in school, we read about the travels of Fa Hien and Hiuen Tsang, Buddhist pilgrims; ibn Batuta, a lawyer; and Marco Polo, a businessmen. Humboldt was the first modern scientist whose travelogues became famous. The New Continent was America; it was Humboldt’s accounts of the Amazon that awed and inspired Darwin and a whole generation of adventurous Naturalists. (The word science was coined only in the 19th century; before that scientists were called Naturalists or Natural Philosophers). Darwin himself traveled to South America, to the coral islands of the Pacific, to Australia and New Zealand. On the ship Darwin read Charles Lyell’s book on geology, and saw evidence of geological phenomena wherever he went, and understood how much geology influenced biology. He formed several ideas about evolution but did not yet publish them.

The young Wallace went to public libraries and read pamphlets written and printed by popularizers of Natural Philosophy. One book that inspired Wallace was Lindsey’s “Elements of Botany.”

In 1848, an economic recession gripped England; Wallace lost his job. He enrolled in Mechanical College, a low cost school set up by industrialists to educate poor youth. There he befriended Henry Bates, another keen naturalist. They read Humboldt and Darwin and dreamed of voyages to the Amazon and discovering new species. In those days, rich collectors in Europe were fascinated by collections of butterflies, beetles, fossils, exotic plants etc and would pay naturalists good money for rare collections. Wallace and Bates hoped to sell such collections to finance their travel and scientific pursuits. They got a chance to travel to South America. For four years they explored the Amazon and its tributaries, sometimes together, sometimes apart. They suffered from all kinds of diseases, barely escaping death a few times. Alfred’s brother who accompanied them was not so lucky; he died of a tropical disease, and Alfred only found out months later. Wallace meticulous collected thousands of species of insects birds reptiles; drew several thousands sketches, and shipped some to his agent in London, who sold a few. But he did not form any scientific theories or publish any papers.

In 1852, he set sail for England. (Bates continued in South America for seven more years.) Misfortune hounded Wallace. His ship caught fire mid-sea. He lost almost all his collections, painstakingly gathered over four years. Wallace escaped on a life boat with some others, but they almost died of thirst before they were rescued by another ship. Wallace returned to England almost as poor as he left it, but his agent had insured his collection, so he was able to salvage some money.

In 1854, Wallace set sail for Singapore, and explored the islands there for the next eight years. and wrote a book about their biology, The Malay Archipelago. He noticed something strange – the birds and animals of Bali were remarkably different from those of Lombok, though both islands were only fifteen kilometers apart. Species on one island, related to Australian species, were totally absent on the other with Asian species; and vice versa. He realized this was true of several islands. Wallace hypothesized that in the remote past one group of islands had been part of Asia, the other part of Australia, and their geological break up was reflected in their species differences. He drew a line on the map demarcating this geological break; this line was later named the Wallace Line by Thomas Huxley. The field of Bio-geography was born, created by Wallace!

He wrote letters to Darwin, who occasionally responded . His first scientific essay on speciation, excited Darwin’s geology guru Lyell, but neither Darwin nor other naturalists were impressed. 

Meanwhile, Lyell urged Darwin to publish his theory of Evolution, but Darwin delayed. Wallace mailed a second essay titled On the Tendency of Varieties to depart indefinitely from the Original Type, which hit Darwin like a bombshell. Darwin was astounded that someone far away with no scientific reputation had so brilliantly and concisely summarised Darwin’s theory.

He regretted having ignored Lyell’s advice on publishing. He lamented that he had lost his precedence of discovery. His conscience would not allow him to betray Wallace’s confidence. But Lyell and Hooker, another naturalist, persuaded Darwin to let them present Darwin and Wallace’s theories jointly, which they did at the Linnaean Society in June 1858.

It was then that Wallace’s greatest act of decency came shining through. He applauded Lyell and Hooker, and thanked them for not taking away the rightful credit of Darwin’s two decades of work and the fame discovery from Darwin! He even published a book titled Darwinism, which explained evolution more clearly and eloquently than Darwin!

References
1.      Darwin’s Armada, Iain McCalman

2.      Contributions to the Theory of Natural Selection, Alfred Russel Wallace

My Blogs on Biology

1ஆல்பிரட் வாலஸ் கண்டு ரசித்த சொற்கத்தின் பறவைகள் 
2Smt Radhika Parthasarathy's Summary of my book review of Darwin's Armada


4. Plant fossils near Madras
5. SymbioGenesis - Lynn Margulis' Supplement to Theory of Evolution
6. கப்பலோடிய ஆங்கிலேயர்
7. Astounding Statistic - Domination of Land Plants

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