Ray Nayler, author of Palaces of the Crow, which was released in March. | Anna Kuznetsova On a cool April morning at the height of Washington, DC’s always brief spring, the science fiction novelist Ray Nayler and I found ourselves in a staring contest with the world’s heaviest flying bird. We were standing at the fenceline of the Kori bustard exhibit at Washington’s National Zoo when the largest of the already enormous omnivores broke away from its flock at the rear of the enclosure and began