Charles Darwin
Charles Darwin (1809-1882) was a British naturalist who completely changed the way humans understand life. By patiently collecting evidence on a famous round-the-world voyage, then thinking carefully for over twenty years afterwards, he worked out the theory of evolution by natural selection. His 1859 book On the Origin of Species is still one of the most important science books ever written. It is the foundation of every part of modern biology.
- Born12 February 1809In Shrewsbury, England
- Died19 April 1882Aged 73
- Famous voyageHMS Beagle1831 to 1836, around the world
- Famous book"On the Origin of Species"Published 24 November 1859
- Other field of studyEarthwormsWrote his last book about them in 1881
- Buried atWestminster AbbeyA national honour
The early years
Charles Darwin was born in Shrewsbury, England, on 12 February 1809 (the same day as the American President Abraham Lincoln, by coincidence). His father was a wealthy doctor; his grandfather was the famous physician and inventor Erasmus Darwin, who had himself written about evolution. The Darwin family was well off, and Charles received a good education, although he was a poor student. He once said: "I was considered by all my masters and by my father a very ordinary boy, rather below the common standard in intellect."
Darwin started training to be a doctor at Edinburgh University but found the medical work too gruesome (operations were carried out without anaesthetic in those days). He switched to studying for the church at Cambridge, but spent most of his time collecting beetles and studying natural history. In 1831, a Cambridge professor recommended him for an unpaid position on a Royal Navy survey ship called the HMS Beagle, which was about to leave on a round-the-world voyage. Darwin was 22.
The voyage of the Beagle (1831-1836)
The Beagle voyage was the formative experience of Darwin's life. For nearly 5 years, he sailed around the world (South America, the Galapagos Islands, Tahiti, New Zealand, Australia, South Africa and back to England) collecting fossils, plants, animals and rocks. He sent thousands of specimens back to England in barrels and crates. He kept detailed journals. He saw an enormous range of habitats and species, more than almost any naturalist of his time.
He visited rainforests in Brazil, the high Andes mountains, the Patagonian deserts, coral reefs in the South Pacific, and most famously the Galapagos Islands off the coast of Ecuador. On the Galapagos he noticed something surprising: each island had its own slightly different versions of the same species of finch, mockingbird and tortoise. Years later he would realise this was a clue to how evolution works.
Darwin's finches
One of the most famous parts of Darwin's evidence was the Galapagos finches. Each of the islands had its own species, with beaks shaped to suit the food available there: thin pointy beaks for catching insects, thick crushing beaks for breaking nuts, long delicate beaks for sipping nectar. Darwin worked out that all of them descended from a single mainland finch species that had colonised the islands long ago. Once isolated on different islands with different food sources, each population gradually evolved its own beak shape. This was natural selection in action.
The long wait
Darwin worked out the basics of natural selection by around 1838, just a few years after returning from the Beagle. But he was extremely cautious about publishing. The idea was explosive: it contradicted the religious view, dominant in Victorian England, that every species was specially created by God. Darwin was deeply religious himself in his youth (although less so later in life) and his wife Emma was a devout Christian. He worried about the upset his ideas would cause.
So he waited. For 20 years he gathered more evidence and refined his ideas, writing books on barnacles, fossil reefs and plant biology, but never publishing his big idea. He was finally pushed into print in 1858 when he received a letter from another British naturalist, Alfred Russel Wallace, who had independently worked out exactly the same theory while working in Indonesia. Worried that Wallace would beat him to it, Darwin and Wallace presented their joint discovery to the Linnean Society in July 1858, and Darwin rushed his big book to publication.
On the Origin of Species
Darwin's book, with the full title On the Origin of Species by Means of Natural Selection, was published on 24 November 1859. The first print run of 1,250 copies sold out the same day. The book set out the case for evolution by natural selection clearly and patiently, marshalling decades of evidence from fossils, breeding, comparative anatomy, plant geography and Darwin's own observations.
The book was the biggest scientific shock of the 19th century. It caused fierce debate among scientists, religious leaders and the general public. Within 20 years, almost every working biologist had accepted that evolution was real (though debates about exactly how it worked continued for decades). Darwin himself avoided most of the public arguments and let other scientists, especially Thomas Henry Huxley ("Darwin's Bulldog"), defend the theory.
The later years
For the rest of his life, Darwin lived quietly at Down House in Kent with his wife Emma and their large family. He wrote more books on plant climbing, orchid pollination, the expression of emotions in animals, and even one final book about earthworms. He suffered from a chronic illness for most of his adult life (probably picked up during the Beagle voyage) and rarely travelled. He died on 19 April 1882 and was buried in Westminster Abbey, just a few feet from Isaac Newton.
Deeper dive: how Darwin's ideas have stood up over 165 years
Darwin published his theory in 1859, before anyone knew about DNA, before Mendel had figured out the rules of inheritance, before anyone knew the age of the Earth was billions (not millions) of years. He had no microscopes powerful enough to see chromosomes, no fossil record going back to the earliest life, no idea how genes worked or what mutations were. Working with these huge gaps in his knowledge, Darwin could have got the big picture badly wrong.
Astonishingly, almost everything he proposed has been confirmed by 165 years of further research:
- Evolution by natural selection: confirmed, with mountains of evidence from genetics, palaeontology, ecology and direct observation in the lab and field.
- All living things share a common ancestry: confirmed by DNA analysis showing the same genetic code across all life.
- Species change slowly over millions of years: confirmed by countless fossil sequences and observed micro-evolution.
- Humans evolved from earlier primates: confirmed by both DNA and a rich fossil record of hominids stretching back about 6 million years.
The main thing Darwin did not figure out was the mechanism of inheritance: he thought traits blended together from parent to child, which would have made his own theory hard to work. The right answer (Mendel's discrete genes) was actually being worked out in the same decade, just over the border in Moravia. The two theories finally came together in the 1930s and 1940s in what biologists call the Modern Synthesis, which combined Darwin's natural selection with Mendelian genetics into the powerful evolutionary biology we have today.
For Darwin's big idea, see natural selection. For the evidence, see the fossil record. For evolution in general, see what is evolution.