We set up camp in a sheltered spot below a six-foot-high ledge of diatomite, a sedimentary rock that's rich in ocean plankton remains. Within minutes, Roberto unloads lounge chairs, sleeping bags, a small table, firewood, and the food - fresh-baked rolls as soft as cotton balls, plus cheese and assorted canned goods. Famished, I grab a can of frijoles, which Roberto opens with his knife, and I eat them straight from the can without even bothering to heat them up. As I wolf down my meal, I realize how extraordinary it is to be dining beneath a 23-million-year-old piece of the ocean floor, and I think that perhaps the remarkable surroundings help make the beans so sweet and tasty, despite their being cold. Later, Roberto builds a campfire and pours boxed red wine into our mugs - he spikes his with Coca-Cola (more diesel) and then we toast: "Salud! Mañana, el megalodon."
For a while, we stop talking about sharks, or anything else for that matter, indulging only in the delicious absence of sound. And when our campfire burns down to a few glowing embers, a moonless dark sky graces us with a larger-than-IMAX screening of a meteor shower.

Search and Rescue
"Wake up, Gail, you can't miss the sunrise," Roberto mumbles. I ­appreciate the 5:15 a.m. heads-up, but I'm not ready to emerge from my bag. Roberto goes back to sleep and starts snoring, but I am so wide awake that I give up. When the sun comes up, I wander far enough to feel entirely alone in the mysteriously beautiful desert that lacks living creatures, rainfall, or anything that has a scent. An hour later, Roberto tracks me down - by following the aroma of my SPF 45 sunscreen, he claims - to bring me a mug of campfire coffee.