Galápagos giant tortoises show that in evolution, slow and steady gets you places

Giant tortoises may not seem like high achievers, but their remarkable spread and diversification indicate otherwise

"As I was walking along I met two large tortoises, each of which must have weighed at least two hundred pounds: one was eating a piece of cactus, and as I approached, it stared at me and slowly stalked away; the other gave a deep hiss, and drew in its head. These huge reptiles, surrounded by the black lava, the leafless shrubs, and large cacti, seemed to my fancy like some antediluvian animals. The few dull-coloured birds cared no more for me, than they did for the great tortoises."

On a hot September day in 1835, Charles Darwin met his first giant tortoise on Chatham Island, part of the Galipagos archipelago. After visiting other islands in the archipelago, he came to realize that each island had its own, but slightly different giant tortoise. This was already known by the natives, who could distinguish the tortoises from different islands, but Darwin was struck with wonder (he even brought some tortoises back to Europe as pets). Eventually, his wonder forever changed our understanding of the natural world.