During a brief 10-month period ending in May 1859, Charles Darwin, a self-taught amateur naturalist, sat in his study and wrote feverishly, virtually from memory, a 155,000-word ‘abstract.’

He called it ‘my abominable volume’ because the writing was all-consuming, hurried and painful. He had, after all, been secretly composing and refining his ideas for more than 20 years.

The book, ‘On the Origin of Species,’ was an instant success. The first printing was in Nov. 24 1859 and all 1,250 copies sold on the first day. The book went through five more additions during Darwin’s lifetime and has never been out of print. It ranks among the top 10 best-selling books of all time, which is astonishing given its scientific content. It is still revered by scientists today, even though it was written for a non-scientific audience.

In writing ‘On the Origin of Species,’ Darwin had two principle goals: To show that species change over time (descent with modification) and natural selection is the process producing the change. The fixity of species had long been under attack, and Darwin’s first goal was not considered to be revolutionary.

As Charles Lyell, a British geologist remarked, ‘transmutation (the older term for evolution) was hanging tense in the air.’ But the second goal, evolution by natural selection, represented a fundamental shift in thinking’mdash;one that is still not accepted by some of America’s citizenry today.

In the words of evolutionary biologist Francisco J. Ayala from the University of California, Irvine, natural selection accounts for ‘design without a designer.’ The genius of Darwin was to turn the old argument from design upon its head.

The marvelously constructed and beautiful living forms we see around us are not the miraculous arbitrary productions of a supernatural creator, but instead have developed gradually over eons of time by means of a purposeless blind process of random genetic variation followed by differential reproductive success.

Even humans, as Darwin well knew, are a product of natural selection and are just one of millions of species. As Daniel Dennett, philosopher at Tufts University said, ‘Darwin taught us that a mindless process could produce a mind.’

The argument style used by Darwin in ‘On the Origin of Species’ is unassailable. He used what is called consilience of induction, whereby multiple lines of evidence all converge upon a single common conclusion.

These multiple lines of evidence were embryology, biogeography, vestigial (rudimentary) organs, comparative anatomy, domestication of plants and animals, and fossils. To this list we can now add molecular biology.

Evolution by natural selection stands as the single greatest discovery in biology. The second greatest discovery occurred in 1953 when James Watson and Francis Crick published the structure of DNA. This ushered in the second Darwinian revolution, which continues today at an ever accelerating pace.

The only figure in ‘On the Origin of Species’ is the ‘tree of life’ sketched by Darwin himself. It is a graphic depiction of common origins and descent with modification. Today researchers are probing the deepest levels of life– gene structure and regulation.

Darwin would be thrilled with their findings. The science of DNA has confirmed the ‘tree of life’ and vindicated nearly everything said by the great man.

‘On the Origin of Species’ was a stunning achievement, especially in light of how little was known in Darwin’s day about fossil records, the Earth’s age, and inheritance. His insight ranks among the greatest achievements of mankind, and evolution by natural selection is the most powerful idea in science today.

Modern biology is inconceivable without Darwin, which includes fields such as ecology, genetics, molecular biology, behavior, and medicine. Darwin’s ideas are also having a profound impact upon the fields of psychology and sociology.

Beginning in the 1940s, evolution by natural selection was accepted as fact by the scientific community. It is just a matter of time before it’s accepted by virtually all Americans.

After all, it took 300 years to complete the Copernican revolution, and it has only been 150 years since publication of ‘On the Origin of Species.’