200 Years of Adventure and Discovery

Sean B. Carroll, 02.10.09, 12:00 AM EST

Charles Darwin wasn't the only scientist with spirit. Less than a year into his voyage on the HMS Beagle, Charles Darwin realized that what was supposed to be a two-year surveying expedition was going to be a much longer journey. Plagued by constant seasickness and increasingly homesick, Darwin confessed in a letter to his mentor, botanist Rev. John Henslow, "I know not, how I shall be able to endure it."It would be three more years before the Beagle would reach the Galapagos Islands. Had Darwin abandoned the voyage anytime before then, he would not have seen the creatures that inspired his revolutionary theory.

But Darwin did not quit. He braved the notoriously fierce storms rounding the Cape Horn, sailed the Strait of Magellan in the dead of winter, climbed the Andes, witnessed a devastating earthquake, ventured inland among hostile natives and put up with the increasingly unpredictable whims of the ship's captain. How did he bear it all? What sustained Darwin through the perils, physical hardships and loneliness of his epic five-year adventure on the Beagle?Author C.W. Ceram described adventure as "a mixture of spirit and deed." Great adventures and great deeds require great spirit--a spirit that manifested itself in Darwin as the passion to explore (to walk where no one else had walked) and in the thrill of discovery (in seeing what no one else had seen). It was also nourished by letters from Henslow, who gently encouraged his former pupil: "If you propose returning before the whole period of the voyage expires, don't make up your mind in a hurry. … I suspect that you will always find something to keep up your courage."

Indeed, Darwin did find some things--and that is why this year we celebrate the 150th anniversary of the publication of On the Origin of Species and, on Feb. 12, Darwin's 200th birthday. Comment On This Story But we should take this opportunity to celebrate more than just one man and an idea. We should celebrate the spirit that drove Darwin and many other exceptional people to explore previously unseen parts of the world and to unearth the history of life. Their adventures and discoveries have transformed our view of nature and our place in it.

I will mention just a few of these less heralded explorers.

The development of the theory of evolution and its early acceptance in scientific circles owes a considerable debt to two other men, Alfred Russel Wallace and Henry Walter Bates, who undertook even longer voyages under more difficult conditions than Darwin.Wallace and Bates became friends through their shared hobby, insect collecting. Though both left school at age 13, they nurtured an interest in natural history. They hatched a scheme to travel to the Amazon and ship specimens back to England to pay their expenses. Unlike Darwin, who had no scientific idea in mind at the outset of his voyage, Wallace was keen "to gather facts toward solving the problem of the origin of species."

Wallace and Bates arrived in Brazil in 1848 and soon split up to cover more territory.Over the course of four years, Wallace ventured 2,000 miles up the Rio dos Uaupes. But by 1852, he had had enough. Sick, and worn out from caring for a menagerie of live animals he hoped to bring back to the London Zoo, he made his way downriver, gathered up many crates of specimens he had stored and boarded a ship for home. Four weeks out of Brazil, however, the ship caught fire. Wallace only had time to grab a few shirts and drawings before getting into a lifeboat and watching the ship burn and sink along with all of his specimens. He spent 10 days--adrift, sunburned, parched and drenched with sea spray--before being rescued. Though he swore to himself on the voyage home never to venture out on the ocean again, he soon broke that resolution. He voyaged to the Malay Archipelago for what turned out to be an eight-year journey, island-hopping from Singapore to New Guinea. The different species on different islands played the same role for Wallace that the birds of the Galapagos did for Darwin and led him to the conclusion that species evolved by natural selection.

In the meantime, Bates, Wallace's former collecting buddy, stayed in the Amazon for an incredible 11 years. After experiencing every imaginable hardship--tropical diseases, robbery, malnutrition--he returned the very same year (1859) that Darwin's great book was published. He realized that he had great evidence for natural selection in the wild in the form of harmless species that mimicked the appearance of dangerous or poisonous species. He struck up a correspondence with Darwin, and mimicry quickly became one of the strongest arguments for natural selection.

The Origin of Species set an agenda for paleontology: to find the fossils that would document the origins of major groups. 2009 also happens to be the anniversary of two landmark discoveries in that arena, made by some of the most tenacious and dedicated naturalists who have ever roamed the planet.Although Charles Walcott never finished high school nor earned any kind of degree, he turned a boyhood fascination with trilobite fossils into a career that carried him to expeditions throughout North America, from the bottom of the Grand Canyon to the tops of the Rocky Mountains and eventually to Washington. But despite his duties as director of the U.S. Geological Survey, secretary of the Smithson­ian Institution and an adviser to seven presidents, Walcott always spent summers prospecting in the field. In 1909, at age 59, after riding his horse high up on Burgess Pass in the Canadian Rockies, Walcott found a mother lode of exquisitely pre­served animal fossils. The Burgess Shale, as it was called, contained the first appearance of many major animal groups in the fossil record and vivid evidence of the "Cambrian Explosion" of animal evolution.

It may seem strange now, but for the first half of the 20th century, most anthropologists thought Asia was the cradle of mankind. But not Louis Leakey. For more than 30 years, he and Mary Leakey combed East Africa. They unearthed tens of thousands of tools, but no evidence of their makers until 50 years ago this summer. In July 1959, Mary discovered the first hominid skull at Olduvai Gorge. Her find, dubbed "Dear Boy" (now known as Paranthropus boisei) and dated at 1.75 million years old, electrified the world and swung attention on human origins back to Africa for good. In short order, the Leakeys also discovered Homo habilis and Homo erectus fossils at Olduvai, providing key links in the evolutionary sequence from apes to humans.What the Leakeys and their peers set in motion continues to unfold today; the best days of evolutionary science are far from past. Spectacular transitional fossils have been unearthed in the Arctic, China and elsewhere by a new generation of intrepid explorers and molecular biologists who are currently mining the massive new DNA record to decipher how we evolved. And the question of all questions--the origin of life here and elsewhere in the universe, remains as open and unexplored as the world was to Darwin and Wallace. Great adventures lie ahead.

Sean B. Carroll, a professor of genetics at the University of Wisconsin, is the author of the new book Remarkable Creatures: Epic Adventures in the Search for the Origins of Species(Houghton Mifflin Harcourt).