A reindeer-hide tribal costume from his expedition to Lapland helped Carl… (W.W. Norton & Co. )
The Species Seekers
Heroes, Fools and the Mad Pursuit of Life on Earth
W.W. Norton: 464 pp., $26.95
As prehistoric cave drawings attest, humans have been fascinated by other species since earliest times. But it wasn't until the 18th century that a comprehensive, science-based system for identifying and classifying them was developed. For that we can thank Carl Linnaeus, a Swedish botanist and physician, who first devised a pyramid of categories — including kingdom, class, order, genus and species — into which all life forms could fit.
Linnaeus' "Systema Naturae," published in 1735, got many things wrong, but it was still revolutionary. As Richard Conniff writes in "The Species Seekers: Heroes, Fools and the Mad Pursuit of Life on Earth," the "ability to distinguish one species from another and to sort out the relationships among species was … a critical advance for understanding life on earth." It also, he writes, inspired a great age of discovery, in which a new type of naturalist traveled the globe in search of previously unidentified life forms. In the course of collecting and cataloguing plant and animal species, humans "stumbled from the security of a world centered on our species, created for our comfort and salvation, to a world in which we are one of many species."
The 18th century and 19th century naturalists at the center of this highly readable book were often arrogant adventure seekers, desirous of the status that came with putting their names on previously undiscovered species. But even though they were rarely driven by a pure desire to advance science, many of them were intensely interested in getting things right and in understanding how species fit into their ecosystems.
Though Linnaeus fervently believed that God was responsible for the creation of each and every species, his disciples inevitably began to question that notion. Fossils suggested an array of species that no longer existed (although, as Conniff notes, Thomas Jefferson was convinced that mammoths probably still roamed the vast, largely unexplored West). The questions of the 18th century naturalists led to new ways of thinking, and to a rejection of long-held assumptions about the natural world. This in turn led to the 19th century's theory of evolution.
In covering such a vast sweep of natural history, Conniff gives short shrift to many of the individual characters and their exploits. There is frustratingly little, for instance, about Charles Darwin's voyage on the HMS Beagle. But what Conniff does include is well worth reading, including an excellent analysis of the interaction between Alfred Russel Wallace (whom Conniff calls the greatest field biologist of the 19th century) and Darwin in developing a theory of evolution.
Whereas Darwin spent years collecting his thoughts about how species adapted and changed over time in response to their environments, Wallace came to many of the same conclusions in a burst of inspiration. In 1858, collecting specimens in the Spice Islands near Papua New Guinea, Wallace was forced to his bed with a bout of malaria. He spent the time reflecting on what he had observed in the field and, he later wrote, it "suddenly flashed upon me … in every generation the inferior would inevitably be killed off and the superior would remain — that is the fittest would survive."
Wallace quickly sketched out his ideas about how the survival of the fittest over time would cause the extinction of some species at the same time new ones emerged. When finished, he sent his ideas off to Darwin, with whom he had developed a correspondence.
Darwin was deeply shaken on receiving Wallace's treatise. "All my originality," he lamented in a note to a colleague, "whatever it may amount to, will be smashed." Instead, his scientific friends moved swiftly to set up a joint presentation of the two men's ideas before a meeting of London's prestigious Linnean Society. In their introduction, Darwin's colleagues made clear that while the two men had "independently and unknown to one another, conceived the same very ingenious theory," Darwin, they let it be known, was the deeper thinker, the true theoretician who had first come to the ideas and developed them most thoroughly. The 1858 presentation caused surprisingly little stir. As Conniff notes, "The society's president went home muttering about the lack of any 'striking discoveries' that year. And so began the greatest revolution in the history of science."