A southern flying squirrel (Photo: Joel Sartore/National Geographic) In the course of my work for magazines, I have often traveled to distant places and done odd, even foolish things, the better to understand and write about wildlife. Once, for instance, I strapped on climbing gear for the first time in my life, then inched out on a horizontal line across the corner of a climbing wall, 15 feet above a concrete floor, in an attempt to replicate the web-building behavior of spiders.