Each life proves the need of all others. In a miraculous way, as each natural form is miraculous, the single is also manifold. The rabbit, as it nibbles grass, calls in the hawk. The spider is related, in its reproduction and survival, to the insect it eats. The soil requires microbes to break it down. The growth of plants is directed toward capturing the energy of the sun. Life calls life in the context of earth, water, and sky. Throughout the wide landscape are a succession of environments, with communities adapting to constant change, characterized by so much mutual attraction and repulsion, so many delicate balances, such a variety of response to influence inside and out that there is hardly a stopping point for attention. We study particular environments so as to predict and understand the behavior of animals, the reaction in plants to variations in the intensity of light, or to relative moisture, or to the chemical constituents of the soil. Each place has its character, its complexity, and bounds. But environment is more a characteristic of range than a separation in its own right. All migration says so. The division between a pond and its surrounding woodland is fairly distinct. A pond is an entity unto itself. So is the division between salt water and fresh. But the frog that lays its eggs in a pond may travel through the woods during the summer. The salmon, the alewife, and the shad reproduce in fresh water and grow up in the sea. Eels do the opposite. In a sense each area has its representative, like the water birds, from petrels that spend most of their lives over the open ocean, to fresh-water ducks dabbling among the reeds. There are herons adapted to spear fishing in the shallows; terns that dive for fish in surface waters; others that swim after them under the water. Some of the adaptations are so precise that if the particular food supply of a species is endangered, so is existence of the bird itself. On the other hand the very distinctness of each species, sharp-billed, webfooted, with gliders’ or divers’ wings, seems to impart range to countless others, those which exist and have existed, those which may develop in a vast and unknown future. The difference, the space, between a gannet and a dovekie, a great blue heron and a frigate bird, proves all the depths of opportunity. As I look out on the waters to east and west, to north and south, I either see or envisage banks of fog far offshore, warm summer squalls, biting cold air, torrents of brilliance in the sky, leaping and ponderous deliberation in the waves. Warm air meets me from the Bahamas, cold air from the Arctic, and the migrants pass me as they travel in between. This earth, regardless of man’s construction of it, is always re-relating its contexts, playing out new themes ahead.