Endearingly, he sometimes looked past his own theory when face-to-face with some marvel of nature. Once he picked a flower and questioned how such stunning, intricate beauty could simply be the result of random forces. His visitor joked, “My dear sir, allow me to advise you to read a book called
The Origin of Species
.”
As his health continued its decline, Darwin lay on his sickbed in a room filled with inventive experiments to trace the movements of climbing plants. He would stare at potted plants for hours—did their tendrils go clockwise or counterclockwise? Which plants moved faster?
He also kept working on a sort of sequel to
Origin
, what he called his “Man book.” In it he actually stated for the first time the ideas he’d previously been ridiculed for. With
The Descent of Man and Selection in Relation to Sex
, published in 1871, he focused his theories of evolution on humans. Humans, he theorized, were part of the animal kingdom. (Teasingly, he once said his own Emma was “the most interesting specimen in the whole series of vertebrate animals.”) He presented evidence for the connection, such as the fact that diseases could be communicated between man and other animals, proving “the close similarity of their tissues and blood.”
He noted that from what we know of the development of human fetuses, we could conclude that our prehistoric ancestors, both male and female, were covered in hair, and both had beards. From a mass of evidence like this, he concluded: “We thus learn that man is descended from a hairy quadruped, furnished with a tail and pointed ears, probably arboreal in its habits, and an inhabitant of the Old World.”
This was arguably the most controversial sentence ever written in science. He didn’t mean that man was descended directly from monkeys, but that both man and monkey were descendants, with modifications, of a common hairy primate ancestor. He had no prehistoric human fossils to work with, but our skeletal resemblance to gorillas and chimpanzees, animals of Africa, allowed him to speculate that this was where humans had first developed. He suspected that someday fossils would be found of an “intermediate form,” a creature in between man and his apelike ancestor.
Grouping humans with the rest of the animal world was in no way demeaning to humans, not in Darwin’s mind. Underscoring what makes us human (the ability to reason, making tools, self-awareness, language, abstract thought, moral sense, appreciation for beauty), he pointed out simpler forms of the same behaviors in animals. All creatures are connected, all part of the tree of life. Human civilization had tempered the brutal “survival of the fittest” battle—we have the potential to protect life with medicines, caring for the weak and helpless,
not
letting them die.
Descent of Man
sold well, not provoking a furor. His work was becoming more and more socially acceptable, much to his relief—“everybody is talking about it without being shocked,” he noted. The first children’s books on evolution were appearing. Charles Lyell was starting to use the phrase “missing links”—exactly what Darwin had predicted with “intermediate forms” connected by common descent.
The following year, at age sixty-three, he published
The Expression of Emotions in Man and Animals
. Readers were fascinated with his ideas about the similarity of facial expressions among people and animals all over the world. One of the first books to feature printed photographs, this was his biggest bestseller thus far.
His next book,
Insectivorous Plants
, was followed by
The Power of Movement in Plants
, written with his son Francis.
In 1876, he started writing an autobiography. It was not meant for publication, but a grandchild was on the way and he wanted to share his story with future generations of Darwins. He avoided anything too emotional or painful or controversial.
He did worry that his mind was atrophying, becoming “a kind of machine for grinding general laws out of a large collection of facts.” But he never lost his child-like sense of wonder about nature, the trait that had started him asking so many questions. One of his sons remembered his gentle touch of a flower—“it was a kind of gratitude to the flower itself, and a personal love for its delicate form and color.”
And when his grandson Bernard arrived, he didn’t study him scientifically as he’d done with his own children. His simply enjoyed their daily conversations and walks around the garden, timing Bernard’s tricycle races up and down the path—just for the joy of being with him.
Thinking about his daughter Annie still made him cry. When the germ theory of infection was finally developed in 1877, he realized how powerful the tiny bacteria were, how much the new research could have helped Annie.
He published his earlier notes on “The Natural History of Babies” as “A Biographical Sketch of an Infant.” One of the first articles on child behavior, it led to new research on infant development—what was due to nature, what was because of nurture.
His last book was on worms, which had always mesmerized him. “He has taken to training earthworms,” wrote Emma, tolerant as ever. He believed that lowly worms, with their gradual but significant effects on soil, were shortchanged by scientists—they were clearly creatures “which have played so important a part in the history of the world.” Now he tested their behavior. Did they react to tobacco fumes, a whistle blowing, vibrations when Emma played piano? Would they eat the tiny triangles and diamonds he cut out of paper? He would observe them outside by moonlight, or creep downstairs to see what they might be up to in his potted plants. He may not have found emotions in them, but they evoked his—affection, amusement, exasperation.
Weirdly enough,
The Formation of Vegetable Mold Through the Action of Worms
turned out to be a blockbuster. A day after publication, his publisher wrote “3,500
Worms
!!!” Plenty of others found them fascinating, too, and not the least controversial.
Ras was still an important part of his life, a source of gossip and encouragement, a superb uncle to his children. But his beloved brother died in 1881. Darwin called him “the most pleasant and clearest headed man whom I have ever known.”
Less than a year later, Charles Darwin died of heart failure. For all his ailments, he lasted until the age of seventy-three. He worked until two days before his death on April 19, 1882. His last words were to his family, assuring Emma, “I am not the least afraid of death.”
His plan was to be buried alongside Ras and his daughter Annie in the local churchyard. But the family bowed to pressure from his important friends and supporters.
Darwin was given the most lavish of funerals and buried in Westminster Abbey, close to the great physicist Isaac Newton. England’s royalty, leading politicians, scientists, and clergy were all in attendance.
The worm book had been a fitting end to his career—billions of worms, over billions of years, turning over soil, changing the earth, the tiny accumulations of change he loved to think about. Humble, agreeable creatures—nice ones.
CHAPTER TWELVE
Darwin Never Dies
SO MUCH HAS been written about Charles Darwin. Why add another book to the pile?
Because two hundred years after his birth, many people still don’t understand his work, and the debate over it still rages.
Darwin’s theory of evolution by natural selection opened up an exceptionally rich, yeasty area for further study in biology. As an explanation for biological change, a framework for investigation, Darwin’s theory is priceless. As a well-known 1973 essay puts it, “Nothing in biology makes sense except in light of evolution.”
But Darwin’s reach stretched farther than biology. His work was a spur to many fields of study in the nineteenth century, leading to waves of progress in psychology, anthropology, medicine, agriculture, and biotechnology, and had an indirect effect on art, literature, and philosophy. It was part of a serious shift in thinking—the universe is not permanent but fluid, changeable. Moreover, all creatures on Earth share connections. He flung open the door to huge areas of ongoing research. Thanks to his painstaking labor, science in general became more established, more of a discipline.
Then, at the turn of the twentieth century, Gregor Mendel’s brilliant work in genetics became known and widely accepted. The Austrian scientist had died in obscurity in 1884. It took until the 1930s before scientists realized how much Mendel’s work vindicated Darwin’s. Passing traits down from one generation to the next—Darwin knew this happened; Mendel showed exactly how it worked.
Combining Mendel with Darwin is known as the “modern synthesis,” and it forms the basis of all modern biology and genetics. Scientists consider it the best way of understanding life on Earth, the similarities and differences among living things over time, and what might happen in the future.
Scientific evidence for Darwin’s theory mounted and became overwhelming. Marie Curie’s discovery of radioactivity in the 1890s led to carbon dating, which confirmed that the earth was much older than those before Darwin had believed. Biblical scholars had established the Creation at 4004 B.C. Today the latest estimate of our planet’s age is about 4.5 billion years old.
Transitional fossils—the “intermediate forms” he predicted—continue to be found. One of the major finds was Lucy, the fossilized skeleton of a creature less than four feet tall, with some ape traits and some humanlike traits, discovered in Ethiopia in 1974. Lucy (named after the Beatles’ song “Lucy in the Sky with Diamonds”) is estimated to be 3.2 million years old.
In 2006 University of Chicago researchers discovered the tiktaalik, a transitional species of fish. Estimated to be 375 million years old, with fins that functioned like legs, it was a transition between fish and four-legged animals.
The most hardened resistance to Darwin’s theory is in the United States, where scientific literacy lags behind that of other industrialized nations. A significant percentage of Americans do not accept the theory of evolution and think that all the supporting evidence for it has been somehow faked or staged.
In the United States the Constitution provides a separation of church and state, meaning the government does not support any particular religion. Public schools, funded by the government, therefore, do not teach religion. Yet, through court cases, religious groups have long tried to keep Darwin out of the classroom on the basis that his theory contradicts the Bible’s story of Creation.
The most famous court case involving evolution was the “Monkey Trial” of 1925.
John Scopes, who taught biology in Tennessee, discussed evolution with his students, in violation of the new state law that made it illegal to teach anything that contradicted the biblical story of Creation.
Scopes was arrested, and at his trial, lawyers on both sides argued passionately for ten days. The entire nation was spellbound. Scopes was found guilty, which led other states to ban the teaching of evolution.
Later on, Scopes’s conviction was overturned on a technicality, and every subsequent court case since then involving the teaching of evolution has resulted in a verdict supporting the separation of church and state.
Yet in the last fifty years, in the United States creationism (a word coined in 1868 to describe opposition to Darwin) has become more popular than ever, its proponents claiming scientific evidence in support of the biblical version of Creation. Intelligent Design, a concept introduced in 1989, is a variation on creationism stating that an intelligent being—never specifically called God—is the controlling force behind life on Earth. Creationists argue that their theory of the beginning of life should be included in textbooks alongside evolution.
It is important to note that many scientists with strong religious beliefs see no conflict between science and their faith in God. These are just two different ways of understanding the world and don’t have to cancel each other out. In September 2008, the Church of England, in advance of the two hundredth anniversary of Darwin’s birth, issued a belated apology to Darwin “for misunderstanding you and, by getting our first reaction wrong, encouraging others to misunderstand you still.”
So much of cutting-edge science is based on Darwin. Since evolution is ongoing and unpredictable, we need to learn about it to find ways to solve problems—what we can do to prevent animals from becoming extinct and bacteria becoming resistant to antibiotics, and to help us to identify and treat new viruses like the one that causes swine flu.
Today, to some extent, we can control things in nature that would have killed us in the past—we have vaccines for smallpox, for example. We no longer have to be the fastest or strongest in order to survive, as long as we have access to proper medicine. But will advances in health lead to even more severe overpopulation? What climate changes are in store for us and how will we adapt? In the future, will we genetically engineer ourselves?
So many questions, so many intriguing topics to explore and debate. Were he still here, Darwin would be astonished, but he’d adapt—and he’d be furiously taking notes.
SOURCES
(*especially for young readers)
BOOKS
Berra, Tim M.
Charles Darwin: The Concise Story of an Extraordinary Man
. Baltimore: Johns Hopkins University Press, 2009.
Browne, Janet.
Charles Darwin, Volume 1: Voyaging
. New York: Knopf, 1995.
Browne, Janet.
Charles Darwin, Volume 2: The Power of Place
. New York: Knopf, 2002.
Browne, Janet.
Darwin’s Origin of Species: A Biography
. New York: Atlantic Monthly Press, 2006.
Darwin, Charles.
On the Origin of Species: The Illustrated Edition
, edited by David Quammen. New York: Sterling, 2008.
*Heiligman, Deborah.
Charles and Emma: The Darwins’ Leap of Faith
. New York: Holt, 2009.