This alone makes the Galapagos special. But the islands' scientific significance did not end with Darwin's visit in 1835. Evolution is most apparent in places like the Galapagos, where the environment is stripped bare. Few plants and animals could reach this oceanic archipelago, which erupted from the sea over the past 10 million years, and fewer still can endure its arid climate and volcanic terrain. Those that do adapt to local conditions and diversify to fill niches not open to them elsewhere.
New species evolve in short order.
Half of the native plant and animal species are found nowhere else on Earth. The central role played by the Galapagos in Darwin's discovery of evolution makes it a place of continuing interest to biologists. During the late 1800s and early 1900s, a series of major scientific expeditions visited the archipelago from the United States, trying to resolve outstanding questions in evolution theory. More recently, David Lack and Peter and Rosemary Grant have used the islands' diverse array of endemic finches to unravel the workings of natural selection. Their work remains the most influential field studies of its kind ever conducted.