Amphibian Image Gallery
Amphibian Image Gallery

The sight of a "Darwin fish" may inspire anger, pride or even laughter, but it represents one of the most important turning points in human history. See our collection of amphibian pictures.

Image courtesy Darwin Fish Wholesale

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Introduction to How Charles Darwin Worked

­At some point, you've probably seen a simple emblem gleaming on the back of an automobile or at the end of a necklace: a single line curved back on itself to form the unmistakable shape of a fish. Dubbed an ichthys, this emblem serves as an expression of Christian faith, sometimes earning it the less esoteric classification of "Jesus fish." Several variations on this design exist, but none stirs more emotion than that of an ichthys sprouting legs, walking, ­with the word "Darwin" etched across its body.

The meaning of this legged icon isn't lost on many. When brandished, it advertises belief in Charles Darwin's theory that the species of Earth were not created as-is by God, but rather evolved from more primitive forms. The "Darwin fish" takes religiou­s iconography, splices it with science textbook illustrations and makes a statement on the fundamental divide between creationism and evolution.

­In an age where just about anything is fair game in the rear-bumper exchange of ideas, it's easy to dismiss these battling bits of plastic and chrome. But no matter how haphazardly the symbol pops up today, the struggle the Darwin fish represents was no laughing matter in the 19th century. At the time, the ideas behind the original ichthys still held sway over Western civilization and its sciences. Nature was viewed as harmonious and static. A divine hand had created Earth and all the creatures in it, crowning humanity as its master. The world might have operated under natural laws, but its genesis was wrapped in allegory, myth and faith.

All of this was set to change, however. Scientists were making great strides in understanding the natural world, and conditions were ripening for a fundamental shift in the way humanity viewed its place on Earth. Just as a machine may harness enormous energies and focus them through a single mechanical part, so too one man arguably became the fulcrum on which science and, subsequently, Western civilization shifted. With his book "On the Origin of Species," Charles Darwin ushered in a true paradigm shift, changing our understanding of the world.

­In this article, we'll look at the events that led Charles Darwin to write "On the Origin of Species," its groundbreaking influence and the war of ideas that continues to play out in its wake.

Charles Darwin proved to be one of the most inflectional men of his century, despite a less than spectacular early life.

Louie Psihoyos/Science Faction/­Getty Images

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The Birth of Darwin's Theory

As a staunch agnostic, the elder Charles Darwin probably would have scoffed at the notion that he was destined to usher in such a drastic cultural change. Looking back at Darwin's early life and education, it's hard to say a path to greatness was truly paved for the future scientific icon. The second of six children, Darwin was born to be a proper English gentleman. His father, Dr. Robert Waring Darwin, sent him first to Anglican Shrewsbury School and then to Edinburgh Univers­ity, where he hoped his son would benefit from a solid science education and follow in his footsteps.

­Much to the elder Darwin's disappointment, young Charles despised anatomy and surgery, despite a fascination with the natural sciences. He had no qualms dissecting beetles and sea slugs, but grew nauseated at the thought of cutting into a human patient. Judging that his squeamish son wasn't cut out to be a physician, Robert Darwin sent him to a third school, Christ's College in Cambridge, figuring the hapless youth was best suited for religious life as a country parson.

Having hardly set the world afire with his accomplishments, the 21-year-old Darwin might well have continued his uneventful life. Despite an excellent scientific education and exposure to the more radical scientific theories of the day, he seemed poised to follow the wishes of his domineering father and spend the rest of his life as a religious man with mere scientific hobbies. Then, in 1831, Darwin received an invitation that would change his life.

Robert Fitzroy, a 26-year-old aristocrat, was slated to captain the HMS Beagle on a government-sponsored voyage to chart the coastal waters of South America. Fitzroy was prone to spells of depression if bored, so he wanted to bring along a good conversationalist to keep his spirits up. As ironic as it may seem in hindsight, Darwin was only invited on the trip because he was a young upper-class gentleman who could hold up his end of a conversation.

­The resulting five-year voyage had a profound impact on Darwin, allowing him to leisurely explore the fauna and wildlife of South America and its various islands, such as the Galápagos. In fact, the young naturalist spent two-thirds of the voyage on dry land while the Beagle charted the coastline and plotted ocean depths. During his travels, Darwin compiled notes and collected specimens of 1,500 different species, many of which European scientists had never seen before. He sent these findings back to England, quickly establishing a name for himself at home.

As Darwin surveyed the vast variety of plant and animal life, a theory began to form in his mind: that the rich variation he encountered was due, not to divine creation, but to the process of natural selection. He compared the variety found in modern specimens to those preserved in fossils and theorized that new species derived from older, similar forms of life.

­He returned to England a respected and famous scientist, but also carried back an idea that would change the world.

A bust of Charles Darwin immortalizes his features, just as his book "On the Origin of Species" immortalizes Darwin's name.

Shaun Curry/AFP/Getty Images

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Penning "On the Origin of Species"

Charles Darwin was a celebrity when he returned to England from his five years aboard the HMS Beagle. As such, he also was free from the religious life his father had intended for him. Instead of serving the Church of England, he studied his collected specimens. After all, he suddenly found himself brushing shoulders with members of Europe's scientific elite -- individuals whose respect he intended to earn.

­Fossils and bird specimens especially interes­ted Darwin. In the fossils, he saw forms of extinct life similar to those thriving in the present. Birds, such as those brought back from the Galápagos Islands, provided a curious puzzle: What he first took for different species were actually numerous varieties of the finch family. Details such as these suggested that past species had adapted and competed with each other for survival. The winners become today's life forms and the losers became extinct -- and the competition continued in the present.

It's important to note that scientists in Victorian England lived drastically different lives from those of their modern counterparts. For instance, Darwin never held a paying job his entire life. As an English gentleman, he followed the acceptable path in life: living on inherited money in a large country home. Plus, he managed to essentially double-dip into his grandfather's china fortune by marrying his first cousin Emma. With these finances in place, he was able to pursue his scientific passions with gentlemanly dignity, first in London and then at Down House, the Darwin's' family home for the next 40 years.

Darwin toiled with various studies and experiments for two decades following his return, generating findings to back up his theories, all the while drafting a three-volume work tentatively titled "Natural Selection." The work was a departure from the predominant theories of the day in that it was a nonreligious biology. Up until Darwin's time, even naturalists believed God had independently created each species. Darwin's theories not only presented a world where natural selection drove the steady modification of species, but also suggested that humans shared common ancestry with the rest of the animal kingdom. This idea alone was profound: It meant that humans were not the God-ordained masters of the Earth, raised up from the dust on the sixth day of creation. Humans were merely animals that had evolved to their current state.

The radical nature of this idea was not lost on Darwin. Other scientists published similar evolutionary theories, only to endure public ridicule at the hands of the press. He set out to avoid this fate by painstakingly assembling as much evidence for his theories as possible. He knew that both the church and the public would react angrily, and was racked by fear and anxiety over their inevitable outrage. In his writings, Darwin compared sharing his writings with friends to "confessing to a murder" [source: American Museum of Natural History].

Delayed by personal illness and the deaths of two children, Darwin was finally spurred on to publish his theories when he received a letter from fellow Englishman Alfred Russel Wallace. A specimen collector working in the Malay Archipelago, Wallace had developed a very similar theory. Despite his apprehensions, Darwin didn't want to see recognition and nearly 30 years of research slip through his fingers. At the urging of friends and colleagues, excerpts from both Darwin's and Wallace's works were presented at the Linnean Society on July 1, 1858.

The following year finally saw the publication of Darwin's theories under the title "On the Origin of Species by Means of Natural Selection, or the Preservation of Favored Races in the Struggle for Life."

This 1860 London Sketchbook illustration typifies the criticism Darwin's theory received.

Hulton Archive/Hulton Archive/­Getty Images

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A War of Ideas: Catastrophism, Creationism and Natural Selection

"On the Origin of Species" hit the market in November 1859. At the time, its 50-year-old author was still recovering from nausea at a secluded Yorkshire spa. Darwin fretted over the impending world reaction. He wrote letters to several prominent scientists, forecasting their initial reactions to his theories. "How savage you will be, if you read it," he wrote in one letter, "and how you will long to crucify me alive!" [source: Williams]. A war of ideas was brewing, and Darwin dreaded the coming storm.

­The theory of evolution had been around for decades, but it wasn't the sort of theory most respectable naturalists supported. It conflicted with predominant religious, social and scientific beliefs. Most scientists believed in a natural world that was much like a manufactured clock: God had created it and left it to simply tick along in unchanging harmony. George Cuvier explained the disappearance and emergence of life forms within a given area with natural disasters, in a theory called catastrophism. In this, one life form would become extinct following a volcanic eruption, and then new life forms would move in from a nearby area. The theory accounts for change, but without questioning divine creation or defining a truly fluid, changing system.

In "The Origin of Species," Darwin presented the theory of evolution with the mechanics of natural selection and painstakingly backed it up with research. But it would take more than diligent lab work to win everyone over -- it would take breeding and social status. Remember, this was Victorian England, and upper-class intellectual elites dominated the sciences.

Alfred Russel Wallace may have developed the idea of natural selection independently, but in addition to lacking Darwin's wealth of data; he also lacked his contemporary's stature. Darwin was a famed gentleman with several publications under his belt. While Darwin had never been forced to hold a paying job, Wallace struggled to finance his studies by selling specimens to wealthy collectors. Members of the scientific community looked down on the likes of Wallace as a mere tradesman.

Darwin quickly became a rallying point for evolutionary theory, with flocks of loyal scientists rushing to support him. In many ways, their effort resembled a modern-day public relations campaign. His supporters wrote multiple, positive reviews for publications and attended debates (the last place Darwin wanted to be) on the author's behalf. Biologist Thomas Henry Huxley regularly defended the author, earning him the nickname "Darwin's bulldog."

This arrangement allowed Darwin to seclude himself with his work and family, while Huxley and others fought off detractors and brushed off snide insults. As Darwin predicted, the religious community found his theories distressing and the media savaged him, stating outright what Darwin had skirted around in the book: Evolution meant that man descended from apes.

Meanwhile, Darwin struggled through health problems at Down House, corresponded with peers and continued his experiments with orchids and worms to refine his theories. Yet while he was a man driven by his work, his findings taxed him at times. When issues of inbreeding arose in his later works on flowering plants, he grew distressed over how his own offspring, born to Darwin's first cousin, might be affected. He would publish 11 more works before 1882, when, at the age of 73, he died of a heart attack.

­It would be years before the majority of biologists accepted natural selection as the driving force of evolution, but Darwin had devoted his life to theories that would change the world.

Darwin's work continues to resonate through modern society, as humans deal with the notion that while we're a product of evolution, we're not the finished product by far.

Leon Neal/AFP/­Getty Images

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Darwin's Legacy

It's difficult to overstate Charles Darwin's influence on modern biology. His theories led to a complete divergence from religious biology, altering the way scientists view life itself. Whether you're digging up dinosaur bones, contemplating life on other worlds or researching a cure for cancer, Darwin's theory of evolution by natural selection plays a vital role. Nevertheless, the influence goes far beyond the sciences, constituting a true paradigm shift in science, society and literature.

­However, not all the ramifications of "Origin of Species" have been positive and beneficial. Following Darwin's death, sociologist Herbert Spencer applied natural selection to the study of conflict in social groups, coining the term "survival of the fittest." Social Darwinism was born out of this concept. Advocates argued that such qualities as compassion, charity and social responsibility were preventing natural selection form taking place.

The argument was simple: Humans had grabbed the crown of terrestrial domination by climbing the ladder of natural selection. In protecting those whom evolution would normally leave behind, humans dulled their chances for advancement. Governments and other human institutions, they argued, should stand back and let competition naturally eliminate the weak. While advocates predicted that this path would prevent stagnation for human race, critics charged the philosophy supported racist, capitalist and imperialistic causes at the expense of human compassion.

Perhaps inevitably, this philosophy led to eugenics. In 1883, a year after Darwin's death, English scientist Francis Galton theorized that it wasn't enough to stand back and let natural selection work its magic. He proposed that humans could speed the process along by simply removing inferior specimens from the equation altogether and encouraging only its strongest members to breed. In this, eugenics was meant to stoke the fire of human evolution. The inevitable flaw, of course, is how do you define what traits are desirable and what causes them? Mental health, physical health and heritage all entered the equation in a clumsy attempt to help natural selection along.

­Popular support for eugenics spread in the early 1900s, leading to both the United States' and Germany's use of forced sterilization programs to curb undesired hereditary traits. In time, the Nazis expanded the program to its Jewish citizens, rationalizing systematic genocide. With each new advancement in genetic science, some worry that we risk unleashing a new kind of eugenics on the world.

Culturally, the war of ideas between creationism and evolution, between the ichthys and the Darwin fish, rages on, just as it did in Victorian England. Some still refuse the idea of man as an evolutionary descendant of apes, while others have found a way to make our modern understanding of science stand side by side with faith in a creator god or gods.

­Expl­ore the links on the next page to learn even more about evolution and natural selection, as well as creationism and intelligent design.

Lots More Information

Related HowStuffWorks ArticlesMore Great LinksSources
  • "Charles Darwin." Britannica Online Encyclopædia. 2008. (Nov. 20, 2008) http://www.britannica.com/EBchecked/topic/151902/Charles-Darwin
  • "Darwin." American Museum of Natural History. American Museum of Natural History. http://www.amnh.org/exhibitions/darwin/
  • Darwin, Charles. "The Origin of Species." The Modern Library. 1859
  • Dean, Eddie. "Scoping Out the Hometown of Darwin's Big American Test Case." Wall Street Journal (Eastern Edition). Sept. 11, 2001.
  • "Eugenics." Online Encyclopædia. 2008. (Nov. 20, 2008) http://www.britannica.com/EBchecked/topic/195069/eugenics
  • Kevles, Daniel. "In the Name of Darwin." PBS. 1995. (Nov. 20, 2008) http://www.pbs.org/wgbh/evolution/darwin/nameof/index.html
  • Moore, James. "The Darwin Legend: ARN Book Review." Access research Network. March 18, 1997. (Nov. 21, 2008) http://www.leaderu.com/orgs/arn/reviews/rev002.htm
  • Muir, Diana. "The Man Who Dared to Climb the Family Tree." Christian Science Monitor. Sept. 26, 2002. (Nov. 20, 2008) http://www.csmonitor.com/2002/0926/p21s01-bogn.html
  • O'Neil, Dennis. "Pre-Darwinian Theories." Early Theories of Evolution. July 10, 2008. (Nov. 26, 2008)http://anthro.palomar.edu/evolve/evolve_1.htm
  • Radick, Gregory. "What If…?" New Scientist. Aug. 20, 2005. (Nov. 20, 2008) http://www.newscientist.com/article/mg18725131.500
  • "Social Darwinism." MSN Encarta. 2008. (Nov. 21, 2008) http://encarta.msn.com/encnet/refpages/refarticle.aspx?refid =761579584
  • Williams, David B. "A Wrangle over Darwin." Harvard Magazine. November 1997. (Nov. 21, 2008)http://harvardmagazine.com/1998/09/darwin.html
  • Yates, Simon. "The Lady Hope Story: A Widespread Falsehood." Critical Thought and religious Liberty. (Nov. 21, 2008)http://www.stephenjaygould.org/ctrl/ladyhope.html

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