Biomimetics

One cloudless midsummer day in February, Andrew Parker, an evolutionary biologist, knelt in the baking red sand of the Australian outback just south of Alice Springs and eased the right hind leg of a thorny devil into a dish of water. The maneuver was not as risky as it sounds: Though covered with sharp spines, the lizard stood only about an inch high at the shoulder, and it looked up at Parker apprehensively, like a baby dinosaur that had lost its mother. It seemed too cute for its harsh surroundings, home to an alarmingly high percentage of the world's most venomous snakes, including the inland taipan, which can kill a hundred people with an ounce of its venom, and the desert death adder, whose name pretty well says it all. Fierce too is the landscape itself, where the wind hissing through the mulga trees feels like a blow dryer on max, and the sun seems three times its size in temperate climes. Constant reminders that here, in the driest part of the world's driest inhabited continent, you'd better have a good plan for where your next drink is coming from.

This the thorny devil knows, with an elegance and certainty that fascinated Parker beyond all thought of snakebite or sunstroke. "Look, look!" he exclaimed. "Its back is completely drenched!" Sure enough, after 30 seconds, water from the dish had wicked up the lizard's leg and was glistening all over its prickly hide. In a few seconds more the water reached its mouth, and the lizard began to smack its jaws with evident satisfaction. It was, in essence, drinking through its foot. Given more time, the thorny devil can perform this same conjuring trick on a patch of damp sand—a vital competitive advantage in the desert. Parker had come here to discover precisely how it does this, not from purely biological interest, but with a concrete purpose in mind: to make a thorny-devil-inspired device that will help people collect lifesaving water in the desert.

A slender English academic with wavy, honey-blond hair beneath a wide-brimmed sun hat, Parker busied himself with eyedroppers, misters, and various colored powders, the better to understand the thorny devil's water-collecting alchemy. Now and then he made soft, bell-like, English-academic sounds of surprise and delight. "The water's spreading out incredibly fast!" he said, as drops from his eyedropper fell onto the lizard's back and vanished, like magic. "Its skin is far more hydrophobic than I thought. There may well be hidden capillaries, channeling the water into the mouth." After completing his last experiment, we gathered up his equipment and walked back to our Land Cruiser. The lizard watched us leave with a faint look of bereavement. "Seeing the devil in its natural environment was crucial to understanding the nature of its adaptations—the texture of the sand, the amount of shade, the quality of the light," Parker said as we drove back to camp. "We've done the macro work. Now I'm ready to look at the microstructure of its skin."