Charles Robert Darwin's On the Origin of Species by Means of Natural Selection, or the Preservation of Favoured Races in the Struggle for Life was published on November 24, 1859. The first printing sold out all 1250 copies in one single day. By the sixth edition of the book the name was shortened to The Origin of Species. The revolutionary theories presented in this book were the foundations of evolutionary biology.

Darwin was born on February 12, 1809, the same day as Abraham Lincoln. He spent his early years in Shrewsbury, England born the fifth child to Robert Darwin and Susannah Wedgwood. Charles’ father and grandfather were both successful physicians and their prestigious positions in the professional community provided him with social and professional advantages.

As a child he showed a strong interest in chemical experiments, but his teachers preferred he learn the classics. He was not an outstanding as a student. At sixteen his father sent him to medical school, but he was upset by patients having surgery without anesthetics. Although disappointed by Charles’ lack of enthusiasm for medicine, his father then sent him to divinity school. Again, Charles did not seem very interested.

At 22 Darwin went on a science expedition around the world. He had the opportunity to find fossils of extinct animals, and he studied plants and animals from all over the world. He returned to London five years later and continued to study specimens from his trip. Darwin was privileged enough to be able to work as an independent scientist. His father was able to support him without Charles ever having to earn a living. He married his cousin Emma Wedgwood on Jan. 29, 1839. The Darwins moved into a house in London, but within three years Darwin's ill health prompted them to move to the country. Charles and Emma Darwin had 10 children together.

These observations from his expedition helped form many of his theories of evolution including:
• evolution did occur,
• the evolutionary changes were gradual taking millions of years
• evolution took place through a process called natural selection
• the millions of species that are alive today were from a single original life form.

While other scientists before Darwin believed in evolution, he was the first scientist to introduce the theory of natural selection. The concept of natural selection was originally developed before any valid theory of heredity existed. Genetics was unknown at the time.

He died on April 19, 1882. There was a rumor that he renounced his theory of evolution on his deathbed but his daughter Henrietta denied this. She claimed that she was at his deathbed and he never recanted any of his scientific views.