Darwin’s Discovery

In 1831, a young, English naturalist named Charles Darwin boarded a ship called the Beagle. His task in a five‑year expedition was to collect and study animal, plant, and rock samples. Darwin would eventually become one of the most famous scientists of his time. He is best known for his contributions to the theory of evolution. He proposed that all living things descended from common ancestors.

What is less well‑known about Darwin, however, was that he was prone to seasickness. Yes. Darwin was a puker. And the reason this is relevant is because, to combat his terrible and constant nausea at sea, Darwin was always the first to go ashore and the last to leave it. And because of that tendency, his collection of samples was larger and more diverse than anyone had expected.

The Beagle’s captain, Robert FitzRoy, kept detailed logs of the ship and its position. Darwin took many notes and also kept a journal. Together, these records help us to know today exactly where they traveled and what they collected.

San Cristóbal mockingbird

Charles Darwin

Where They Traveled

The Beagle reached the Galápagos in 1835 and spent five weeks there. Darwin visited four of the larger islands. San Cristóbal was first. This island is made up of four volcanoes, all extinct, and is home to the oldest permanent settlement of the islands.

San Cristóbal’s dry, rocky coast was not what Darwin was expecting. The island seemed devoid of life. Then he encountered piles of “hideous‑looking” marine iguanas sunning themselves on the rocks.

As he walked on, he found patches of desert plants. In a partially vegetated lava field, he came across two enormous tortoises, grazing on cactus.

It was here that Darwin collected the first species that later would be the foundation of his theory of evolution, the San Cristóbal mockingbird.

Mockingbird Mystery

Floreana was the second island explored by the Beagle expedition. Floreana is the site of the islands’ first “post office,” established in 1793 by whalers. It’s a barrel with a door cut into the side. No stamps needed. Visitors collect and deliver mail by hand across the world. This post office is still in use today.

Darwin spent three days here collecting samples, including a second important bird, the Floreana mockingbird. He saw distinct differences between this bird and the one found on San Cristóbal, which prompted him to pay close attention to Galápagos birds.

On Floreana, Darwin also had a chance encounter with a fellow Englishman named Nicholas Lawson, who was the acting governor for the island. Lawson told Darwin that he could identify which island a tortoise came from just by looking at its shell. Each island’s tortoises were different, he said.

The volcano that is Isabela Island was actively erupting when Darwin explored it. He observed lava flows and smoke coming out of craters. He took detailed notes and collected land iguanas.

female vegetarian finch

small ground finch

Floreana mockingbird

post office barrel

Darwin’s Longest Stay

It was Santiago Island where Darwin stayed the longest, and it was here that he saw what Lawson had described: The tortoises were different. Darwin collected many plant, animal, and rock samples. Yet, he didn’t always know what he was collecting. He didn’t always understand what he was seeing.

Of the mockingbirds, he could already see four different species, each from a different island. He had collected many finches, too, and they all seemed to be different.

When Darwin returned home, he gave his bird samples to the Geological Society of London. The famed ornithologist John Gould examined the finches and found each of them to be different enough to justify at least 14 distinct species. Darwin would ponder these birds for many years.

Life Science

History of Science