American Scientist

Darwin. An exhibition at the American Museum of Natural History, November 19, 2005, through May 29, 2006. Curated by Niles Eldredge

Darwin: Discovering the Tree of Life. Niles Eldredge. xvi + 256 pp. W. W. Norton, 2005. $35.

As I made my way to the American Museum of Natural History to see the new Darwin exhibition there, I confess I was uneasy. Would the display play into stereotypes about Great Men of Science? Would it focus too exclusively on the crosscurrents of 19th-century science? Devolve into figure cult, implying that we can gain genius simply by gazing at Darwin's personal objects and buying a replica of his walking stick afterward?

I need not have worried. The curator, Niles Eldredge, has brought both his intense affection for Darwin and his keen knowledge of evolutionary biology to bear. Eldredge, together with the late Stephen Jay Gould (my former graduate adviser), originated the theory of punctuated equilibrium. Informed by his own deep involvement in one of the most interesting debates in contemporary evolutionary theory, Eldredge has an insider's perspective on Darwin and his contributions. Both the exhibition and Eldredge's companion volume, Darwin: Discovering the Tree of Life, provide new insights into Darwin and the revolution he brought about.

The exhibition assiduously avoids caricature; we see a Darwin who both influenced and was influenced by Victorian society. A surprisingly three-dimensional figure emerges, his life full of foreshadowings and contradictions. We see his passion for the natural world, evidenced by his energetic beetle hunting as a child, transform into the collecting of crucial specimens on the voyage of the Beagle. The analytic and rhetorical skills that served Darwin so well in his scientific life show up early in unexpected contexts. In a disarming letter to his father, for example, the young Darwin anticipates his parents' objections to his undertaking a multiyear voyage as the Beagle's unpaid naturalist. In response to that preemptive missive, his father eventually relents. Twenty-nine years later, Darwin uses the same approach—blunting objections by anticipating them—in "Difficulties on Theory," Chapter VI of On the Origin of Species by Means of Natural Selection.

We are also treated to Darwin's early attempts to reason his way through the world, tackling even the subject of marriage analytically. Two pages of his journal that are on display list arguments for marriage (children, companionship) and against it (less money for books, loss of freedom to go where one likes, being forced to visit relatives). His conclusion, on balance: "Marry—Marry. Marry Q.E.D." This same methodical, reasoning temperament later enables Darwin to coalesce seemingly disparate observations into a coherent theory of organic change.

Contrary to the stereotype of the dispassionate scientist, however, Darwin was a man to whom family and friends mattered profoundly, and many poignant objects in the exhibition remind us of his humanity. On the back of a rare manuscript page of the Origin, we find a drawing, "The Battle of the Fruit and Vegetable Soldiers," by Darwin's young son Francis. Also on display is a keepsake box that holds the belongings of Darwin's daughter Annie. Her death at the age of 10 shattered his tenuous connection to Anglican beliefs. His wife, Emma, worried that his religious skepticism and commitment to material explanation would separate them in the afterlife. In the margins of the letter in which she voiced this anxiety, Darwin wrote, "When I am dead, know that many times I have kissed and cryed over this." He loved Emma dearly and relied on her. Despite their fundamentally different perspectives on the existence of God, he entrusted her, in the event of his death, with the publication of the groundbreaking 1844 essay in which he first laid out the elements of his theory.

Friends and colleagues, too, were of utmost importance to Darwin. Much has been made of his apparent reclusive nature. Historians have often interpreted his move away from London a mere five years after returning from the Beagle voyage as some sort of withdrawal from society. But as the exhibition emphasizes, Darwin remained deeply engaged with the intellectual life of London, Cambridge and the Continent. Prior to the voyage—and with a vengeance upon his return—he stayed in constant contact with major figures in the scientific establishment, seeking their counsel, support and patronage.

These contacts served Darwin well throughout his life, most dramatically in the resolution of the potential disaster that was precipitated in June 1858 when he received from Alfred Russel Wallace  a manuscript in which Wallace outlined a theory of natural selection. Against the advice of his colleagues, Darwin had delayed publication of his ideas for two decades, and now Wallace, who had converged on a very similar mechanism of evolution, appeared to be about to scoop him. Joseph Hooker and Charles Lyell, influential and established scientists, arranged for the unpublished 1844 essay by Darwin to be presented, together with Wallace's article, before the Linnean Society on July 1, 1858.

Born into a comfortably wealthy family, married to his cousin from the even wealthier Wedgwood branch, Darwin was well positioned within the class structure of 19th-century Britain. He grew up surrounded by a large and engaged family of freethinkers and as an adult had servants and allowances to support him in leading a life of reflection, investigation and self-discovery.

Darwin's acceptance at age 19 to the University of Cambridge, where his father expected him to train for the clergy, was virtually a foregone conclusion. There he befriended distinguished older scientists and ambitious young gentlemen. His grandfather, Erasmus Darwin, was a well-known and influential early evolutionist whose name opened doors for Charles. Young Darwin was enmeshed in an intricate web of relationships that assisted gentlemen of means who were seeking to make names for themselves. Moreover, for the first time he was engaged in pursuits that captured his imagination. His affection for shooting and for collecting was being transformed into the study of diversity, his penchant for speculation into a passion for philosophical debate.

Darwin's earnest energy and open character did not go unnoticed by his professors. It was a recommendation from one of them, his mentor John Stevens Henslow, that secured an invitation for Darwin to sail on the Beagle as an unpaid dining companion to the priggish Captain FitzRoy. And Darwin's father eventually agreed to support his 22-year-old son for the duration of the voyage (which ended up lasting five years), forever altering the history of biology.

Like many Victorians, Darwin was a compulsive writer. His written legacy includes, in addition to his enormously influential books, more than 15,000 letters. He also left behind a series of notebooks in which, beginning in 1836, while still aboard the Beagle, he recorded—with remarkable candor and abominable handwriting—most of his scientific ideas. Although the sheer volume of these writings is daunting, what they reveal about Darwin's thought processes makes us lucky to have them. (Much of this material is now available online at http://darwinlibrary.amnh.org/ and at http://www.lib.cam.ac.uk/Departments/Darwin/).

As Eldredge makes clear, both in the exhibition and especially in the superb companion volume, Darwin was uncannily conscious of the way he reasoned. That intellectual self-awareness, coupled with his graphomania, bequeaths to us the genesis of the single most influential scientific theory in contemporary Western culture. From Darwin's earliest flirtations with the notion that species might not be immutable, through the manuscript of his last book, The Formation of Vegetable Mould through the Action of Worms, with Observations on Their Habits, we witness a powerful mind at work.

The deciphering of the notebooks and letters has been an exquisite labor for many distinguished scholars over the past century, and a great deal of effort has been expended on reconstructing the chronology of these writings in search of key junctures and influential events. A whole intellectual cottage industry has sprung up to interpret Darwin's writings, to probe his psyche and to explain many curious aspects of his life (most notably why he waited more than 20 years to publish his ideas on evolution and natural selection).

Darwin: Discovering the Tree of Life is a provocative contribution to Darwin scholarship. In it, Eldredge makes a compelling case that Darwin boarded the Beagle a traditional creationist and disembarked a committed materialist. Eldredge also traces the philosophical transformation that metamorphosed Darwin the methodical observer/experimentalist into Darwin the model of a modern major scientist. Both the exhibition and the companion book trace the emergence in the early notebooks of a set of interconnected general hypotheses: that all life arises from a single ancestor, that all species are mutable, that geographic and temporal changes in species composition are driven by a shared mechanism. One illustration in Darwin's 1837 Notebook B electrifies: We see a genealogical network connecting living and extinct species, illustrating common ancestry, descent and diversification; above it are the words "I think." Darwin had arrived at the seeds of the theory that would transform the way we see the world.

His genius lay not, as heroic reconstruction would have it, in his ability to observe the natural world without preconceptions. Rather, Darwin's ability to discern the incompatibility of existing theories of organic change with the observations he was compiling led to the breakthrough. Once the new theory of organic change began to take shape in his mind—descent with modification through the action of natural selection—the natural world became one vast testing ground. This exhibit is intellectual history at its most thrilling, as we witness Darwin, with his deceptively simple new theory, make a whole set of predictions about the living world. Equally exciting is Darwin's revisiting of well-established observations in paleontology, embryology, comparative anatomy and biogeography, now seen afresh in light of his growing confidence in his theory.

The notebooks, letters and edited manuscripts on display reveal Darwin's many moods. His tentative early speculations yield to his increasing realization that evolution by natural selection accounts elegantly for observations in a range of disciplines. His anxiety about revealing his theory to the outside world ("It's like confessing a murder," he would write to his friend Joseph Hooker) fades as he resolves to bring all of the history of life—including the origin of Homo sapiens—under the umbrella of evolutionary thinking. Today, Darwin's published works stand as a powerful testimony to a towering intellect.

Every object in the American Museum of Natural History, not just the items in this exhibit, bespeaks the influence of Darwin's ideas. We can no longer imagine a world without Darwin, and this exhibition, by giving us the chance to see a visionary idea in the making, helps us understand why.

[Editor's note: The exhibition, which can be sampled online at http://www.amnh.org/exhibitions/darwin/, will travel after it closes in New York in May 2006 to the Museum of Science in Boston, The Field Museum in Chicago, the Royal Ontario Museum in Toronto and the Natural History Museum in London, arriving in England on the 200th anniversary of Darwin's birth in 2009.]