"A paradox to everyone but himself": the naturalist who almost scooped Darwin about natural selection was also an ardent mystic

Natural History, Sept, 2004 by Menno Schilthuizen

The Heretic in Darwin's Court: The Life of Alfred Russel Wallace by Ross A. Slotten Columbia University Press, 2004; $39.50

An Elusive Victorian: The Evolution of Alfred Russel Wallace by Martin Fichman University of Chicago Press, 2004; $40.00

Last month my students and I took a field trip to a small forest reserve a couple of miles from our university campus in Malaysian Borneo. Slip-sliding down a steep jungle path, clutching the soggy stems of wild yams in a futile attempt to stay upright, we collapsed into a pebbly streambed. As we regained our composure and began to look around the steep-sided valley cluttered with the mossy logs of fallen rainforest giants, one of the students, Sharifah Ibrahim, suddenly pointed upward: "A Rajah Brooke!" We all looked, and down came the graceful butterfly, gliding on its long emerald and black wings and settling at a puddle to drink.

A hundred and fifty years ago, Alfred Russel Wallace must have stood in similar awe when he first saw this spectacular birdwing butterfly in Sarawak, a few hundred miles down the coast from where we were hiking. Having arrived in Borneo in November 1854, the naturalist struck up a friendship with the legendary Sir James Brooke, the first "white rajah" of Sarawak. It was Brooke who gave him a specimen of the as-yet-unnamed species. Wallace immediately dispatched a note to the Entomological Society of London, naming the species Ornithoptera brookiana after his new friend, "whose benevolent government of the country in which it was discovered every true Englishman must admire."

It is tempting to see the note as an early sign of Wallace's ability to marry science with social issues and with loyalty to a person or a cause, traits that were to both drive and plague him in his later career. But when the thirty-one-year-old Wallace, as the guest of Brooke, was amusing those at the rajah's dinner table with "his clever and inexhaustible flow of talk--really good talk," as one dinner guest recalls--his career was just beginning.

Born to a middle-class family of scant means, the young Wallace worked in England and Wales as a land surveyor and schoolteacher, all the while educating himself as a naturalist. At the age of twenty-five, he embarked on the life of a traveling collector, living off the sale of his specimens to museums and private collectors in the British Isles. His travels took him first to South America, where he spent four years traversing the Amazon basin. But he lost most of the collection he amassed there when the vessel carrying him back to England sank in the middle of the Atlantic. Undaunted, he spent the next eighteen months mustering the courage and funds for another trip, this time to the Malay Archipelago, where he would spend eight years before finally settling down in his native country.

Traveling naturalists were not uncommon in the nineteenth century, and Wallace probably would have remained relatively obscure had he not had two world-shattering insights during his stay in Southeast Asia. The first came to him around the same time he penned his description of the Rajah Brooke birdwing. It was the height of the monsoon season, and the incessant rains gave Wallace, who was sojourning in Brooke's riverfront villa, little else to do but "ponder over the problem which was rarely absent front my thoughts." Evolution--though not yet called by that name was a hot topic in the mid-nineteenth century. Nobody, however, had a clear idea of what it was or how it might work--nobody, that is, except Charles Darwin, who for ten years had shared his thoughts with only a few friends.

In Brooke's villa, Wallace wrote the treatise now known as the "Sarawak Law." In it he deduces, from the geographic distributions of animals and plants, that ancestor species whose ranges were physically separated split over time into multiple descendant species, a process that biologists today call allopatric speciation. The paper, published in 1855, drew the attention of the leading English geologist of the day, Charles Lyell. Lyell warned his friend Darwin that Wallace seemed on the verge of scooping him. And that, in fact, is what almost happened. Laid up on the island of Ternate in 1858 with a bout of malarial fever, Wallace, in a flash of inspiration, discovered natural selection. When he recuperated, he spent three evenings writing "On the Tendency of Varieties to Depart Indefinitely from the Original Type," and quickly sent the manuscript off to Darwin for comments.

Then unfolded one of the best known episodes in the history of science. Realizing that Wallace, in his but in the Orient, had independently stumbled upon natural selection, Darwin was thrown into a fit of panic and depression. To Lyell he wrote, "Your words have come true with a vengeance.... All my originality will be smashed." Lyell and the botanist Joseph Dalton Hooker helped save the day by arranging for Wallace's "Ternate essay" and abstracts of Darwin's still-unpublished treatises to be read jointly at the July 1, 1858, meeting of the Linnaean Society. The rest is history.