The marine iguana, which is found only in the Galapagos archipelago, spends most of its time sunning itself on the volcanic rocks and sneezing. For nourishment, it dives in the sea and feeds on algae. Consequently, it has to rid its body of sea salt somehow. To do so, it expels a salty mist out through its nostrils—unmistakeably a sneeze—leaving a white coating of salt on its crown until the next time it goes swimming.
I found myself trying to hold my camera still, waiting for the large orange lizard to erupt. Inevitably, the moment my arms gave out and I put down my camera, the iguana would let loose a torrent of sea snot worthy of a National Geographic cover.
The peculiarity of the animals on these islands has fascinated visitors for the past 500 years. Although Charles Darwin spent only a few weeks on the archipelago, the observations he made and the samples of species he took back to England were the basis for his theory of evolution.
Today the Galapagos still attract scientists, and they were among the first places that biologists were able to do what Darwin had thought impossible: to observe natural selection in action over just a few years rather than thousands or millions of generations. Evolutionary biologists Peter and Rosemary Grant have observed finches on the small island of Daphne Major for over a quarter century, and, after painstaking measurements and number crunching, they’ve been able to track how different types of birds’ bodies and beaks are selected for different environmental conditions over time.
The casual Galapagos visitor can’t see natural selection in action, but the peculiar specialization of shape, habit, and diet that the islands’ wildlife has developed over millions of years of isolation is on prominent display. The absence of large land predators has left the birds and animals indifferent to tour groups traipsing through their habitat. Bird mating dances and giant tortoise copulation go on uninterrupted, even with the clicking and whirring of thousands of dollars worth of camera equipment nearby. Snorkelers are themselves observed by curious sea lions that dart around them in the water.
Although many visitors sport Darwin T-shirts and marvel at walking in his footsteps, the draw of the Galapagos is much more Dr. Dolittle than it is Darwin. Even my brother, a hard-nosed evolutionary biologist who spends more time on computer models than he does observing nature in the flesh, admits that the main attraction is being as close as we are to very cute and intriguing animals. And who can blame him? If birds landed on our heads at home, or if deer didn’t dart away at the slightest sound, it might be easier to see ourselves as nature’s friend rather than its foe.