Strung across the equator about 600 miles (roughly 1,000 kilometers) west of South America, this volcanic archipelago sprawls over some 8,000 square kilometers (about 3,090 square miles) of land. The protected marine area that encircles these islands is vastly larger, turning it into one of the world’s most significant oceanic reserves as well as a national park. Hardly untouched by humans despite their isolation, they are now home to a permanent population of around 30,000, mainly on islands with melodious names like Santa Cruz, San Cristóbal, Isabela, and Floreana.
Had I mentioned Charles Darwin above, you’d have guessed the setting at once: the Galápagos, of course. His duties aboard The Beagle—he signed on as its geologist—kept him busy for nearly five years. Interestingly, the 26‑year‑old naturalist spent only about five weeks in the Galapogos—and for roughly half of that time he stayed on the ship, as if the theory of evolution might kindly come to him. He barely gives finches a nod in his diary; these variously beaked birds that later reshaped biology were, at the time, just background. (True, they were competing with Frigates pretending to be red balloons and Boobie in blue socks to say nothing of giant saddleback tortoises.) What really excited Darwun were the rocks and the oddities: frozen lava, giant lizards, and cactus-covered landscapes that looked freshly mintesd.
Remote but not exactly unknown, the islands had already been annexed by Ecuador in 1832, three years before Darwin arrived. Visited by at least one off-course bishop and dozens of whaling ships, it had become a sort of tortoise meat commissionary. Having supplied their own packaging, tortoises stayed alive for months without care before they made it to the crews table. The Beagle might have arrived with Darwin and others aboard primed with a good deal of knowledge about this isolated and mysterious place. It left without more than a hint about how we explain life itself and with some 40 tortoises for its hungry crew.
It is their isolation that I had inferred was the trigger for evolution by natural selection. I scarcely imagined the essential roles played by plate tectonics or hotspot volcanism. A walk across basalt lava fields on Sierra Negra volcano, watching sea turtles and blue‑footed boobies at Los Túneles, or Magnificent frigatebirds wheeling over the small islands of Bartolomé and North Seymour will soon convince you that these islands are home to hundreds of animal and plant species found nowhere else on Earth because the Galápagos Islands are unlike any other place on Earth. Their composition, morphology, and geography are distinctive. Geothermal and volcanic activity—to say nothing of crisscrossing ocean currents—were set in motion by a hotspot some 90 million years ago when dinosaurs reigned. Two hemispheres and three of the lithosphere’s tectonic plates—Nazca, Cocos, and Pacific—converge here. The first name of these islands— “Las Encantadas,” the Enchanted, or Bewitched, Islands—fits perfectly.
These thirteen major islands are home to hundreds of animal and plant species found nowhere else on Earth. The endemic creatures here are so improbable that everyday objects were drafted to help make sense of them: saddleback tortoises, hammerhead sharks, chocolate chip starfish. Galápagos is home to green forests of giant Opuntia cactus plants and pocket‑sized penguins. It has tree‑tall prickly pears and bonsai‑scaled trees standing over surreal, monochrome landscape broken by frozen black lava. You land at the modern airport on Baltra, once a secret WWII airbase, and before you depart you can leave a postcard in an 18th‑century whalers’ barrel on Floreana. Long‑lived tortoises shuffle across some of the youngest dry land on Earth on Fernandina. On Isabela , the Wall of Tears memorializes the penal colony, where convicts and political prisoners hauled useless piles of lava rock. Sea lions drape themselves over park benches and block shop thresholds, attempting to evolve in front of your very eyes into enormous house cats.
The modern Galápagos Archipelago is not just a handful of islands tossed into the Pacific hosting a weird menagerie. It is a set of visible towers and turrets of a vast submerged volcano factory. The thirteen major islands and a scattering of islets and rocks sit on a massive submarine volcanic platform, prosaically named the Galápagos Platform. It, in turn keeps company with the Galápagos Spreading Center—a sort of underwater zip‑seam where fresh seafloor is stitched together. The whole operation is powered by the Galápagos Hotspot, a region roughly 150 kilometers (about 90 miles) wide. Here abnormally hot material rises from deep within Earth’s mantle like a slow‑motion lava lamp. Geologists call this a mantle plume: a column of superheated rock ascending from depths that may reach the core–mantle boundary. As the plume nears the surface, the drop in pressure allows the hot rock to partially melt, feeding basaltic magma chambers that eventually erupt out of shield volcanoes. The hotspot itself mostly stays put while the tectonic plate drifts over it, its low‑slung volcanoes rest like shields resting on the earth and not like beakers. The volcanoes take turns riding the Nazca Plate like packages on a basalt conveyor belt. The islands we see today are only the latest chapter of the story of rising from the seafloor, aging, sagging, and finally sinking back into the Pacific. Eventually they drift eastward toward South America where some of the material helps push up the Andes.
The western islands—Isabela and Fernandina—are the archipelago’s problem children: youngest, rowdiest, and most geologically active. Fernandina, barely 0.7 million years old (a mere 700,000 years), is still very much in its volcanic adolescence, with roughly two dozen recorded eruptions since the early nineteenth century and no sign of settling down. Its 1,476‑meter (about 4,843‑foot) summit is crowned by a caldera so large—about 6.5 kilometers (4 miles) across—that it looks like a giant left a soup bowl on the top of the island in 1968 that bowl lurched downward when sections of the caldera floor suddenly dropped 350 meters (around 1,150 feet) in a dramatic collapse.
Isabela, the archipelago’s largest island with an area of approximately 4,600 square kilometers, presents a unique geological structure: rather than forming from a single volcano like most Galápagos islands, Isabela consists of six separate shield volcanoes: Ecuador, Wolf, Darwin, Alcedo, Sierra Negra, and Cerro Azul. They have coalesced through repeated lava flows filling the straits between them. All of these volcanoes except Ecuador remain active, and Wolf, reaching about 1,710 meters, stands as the highest point in the entire Archipelago.
The first historically documented volcanic eruption in the Galápagos occurred at Wolf Volcano in 1797, inaugurating more than two centuries of recorded volcanic activity. Since that initial observation, the Galapagos has experienced scores of documented eruptions. This remarkable frequency—an average eruption interval on the order of a few years—establishes the Galápagos as one of Earth’s most consistently active volcanic regions.
Volcanism built the Galápagos, but the Pacific Ocena is the lease-holder. Everything here—climate, currents, even the color of the rocks—points to a marine world. Within the boundaries of the Galápagos National Park and Marine Reserve, saltwater vastly outweighs soil. Below that surface lie seamounts, the stumps of sunken islands, a mid‑ocean seafloor‑spreading center, and a saltwater pool for sharks. These waters host one of the richest shark communities on the planet, with upward of thirty species ranging from shy reef specialists to bus‑sized drifters like the whale shark.
Darwin’s finches flicker about, unaware of their place in our understanding of the origin of species on these enchanted islands. Above the ocean and bays, Frigatebirds glide on wind currents but never touch water due to their poor waterproofing. They nest in low scrub on old ash and tuff. During mating season, males inflate red throat pouches. They pose and wait, almost motionless for hours, trying to attract females circling overhead. (You will not find any living thing with such a red in the Galápagos.)
Blue‑footed boobies must secretly appreciate the time‑consuming mating obsessions of these fish‑loving, non‑swimming bullies. Frigatebirds are the pirates of the Galápagos skies, all swagger and sharp angles, cruising overhead in search of the Boobies’s hard‑won lunch. I watched one arrow down on a mother Boobje and shake a fresh fish right out of her beak as she tried to feed her demanding fledgling. This bit of aerial mugging is known, rather politely, as kleptoparasitism.
Seemingly obvious in all this, iguanas are everywhere. The endemic marine iguana moves easily over sharp basalt, bypassing colorful Sally Lightfoot crabs at the water’s edge. They slip into narrow surge channels to graze on algae. Nowhere else do lizards feed in salt water; marine iguanas are the world’s only sea‑foraging lizards. Despite this amazing adaptation, Darwin thought they were hideous, dubbing them “imps of darkness.” Cold‑blooded (evolution hasn’t gotten that far), they regularly warm themselves on land—by which I mean staircases, ledges, sidewalks, benches, any other flat surface, and even along walls. Piled on top of one another like stuffed toys in a child’s room, you can hardly avoid nearly trampling on one—or half a dozen. They seem to have few predators, as pelicans perched nearby focus on fresh fish, not lizard.
Their cousins, the larger land iguanas, are found on dry, sun‑baked patches under giant cactus plant—or just as likely, under your park bench. Large, yellow, and spiked, they eat mostly prickly‑pear cactus and therefore rarely need to drink. They are strange‑eating, strange‑looking, and strange‑acting, which somehow makes them feel exactly right at home here.
What struck me most about the Galápagos was not the strangeness of its creatures, though they are strange. It was the sense that geological force and biological life are not separate stories. They are the same story told in the slow drift of tectonic plates, the side‑shuffle of the Sally Lightfoots, and the dance of the blue‑footed boobies. The Enchanted Islands earned their name honestly: frigatebirds hanging motionless on invisible currents, iguanas still as statues, sea lions curled in doorways as if they owned the place. Stay long enough and it all casts a spell.
The Galapagos rewards lingering. You don’t come here to replicate a string of Intagram posts of you posed in exactly the same way as thousands of others in front of a spectacular scene that millions recognize but few can specify. Instead let the series of smaller and fascinating scenes enchant you in a quieter, more subtle way.
This enchantment, I came to understand, is not magic. It is geology. It is time. It is the long, patient work of a hotspot beneath the eastern Pacific, building islands and destroying islands Geology built the stage on which evolution improvised. Molecular analyses of endemic Galápagos species—including giant tortoises, finches, and iguanas—show that most began diversifying 1.5 to 4 million years ago, coinciding with the formation of the oldest current islands. This pattern indicates that most terrestrial biodiversity evolved in situ through speciation within the archipelago. The tendency for the oldest species to inhabit the oldest islands and youngest species the youngest islands—the so‑called “progression rule”—appears in multiple Galápagos species. Biological evolution tracked geological diversity.
The Galápagos remind us that scientific observation does not dispel wonder so much as relocate it, from the surface of things to the deep patterns that shape them. Perhaps that is the definition of enchantment. To visit here is a gift from nature as well as from the good people of Ecuador. I leave bewitched by what I have seen and, at the same time, astonished by how it came to be.
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