Summer World_ A Season of Bounty - Bernd Heinrich [71]
Morality, it seems to me, concerns not only doing unto others, but also being unto others. I try to connect through a deer in the fall, and perhaps some fish and berries in the summer; and, yes, I do harvest trees and maintain a beautiful forest. The one and perhaps only true religion that I can in good conscience honor is one that encompasses the Earth we walk on and that promotes our well-being and our physical connection to it. Such a religion is based on reverence and respect for maintaining the Creation—whatever origin one either knows or wants to believe. As my friend from California concluded: “Offering oneself to the ravens when the time comes is to me religion at its best.”
16
Extreme Summer
19 May 2006. APPLE BLOSSOMS WERE IN FULL GLORY today, and ruby-throated hummingbirds, bumblebees, and northern orioles were visiting the flowers for nectar. Blackflies were in full glory as well, when the sun was out. But the sunshine didn’t last long, and shortly after dark a thunderstorm blew in. It took only half an hour to pass, but it brought some fireworks. Lightning bolts crackled and ripped across the sky, lighting up the night to make a second of day. Booming crashes followed. One right after the other, they made the earth vibrate and shook the house. Then, after a slight pause, torrential rain gushed down through the trees and pounded the roof. I cannot imagine how birds live through this. How do the baby grackles in the bog keep warm?
SUMMER IS A TIME OF LIFE AND DEATH, IN AN ORCHESTRA of organisms interacting with each other. But summer is determined by two key external variables: temperature and moisture. One affects the other. Thunderstorms come from often distant areas where heat caused evaporation and built up clouds. Rain occurs as the clouds encounter temperatures below the dew point to cause condensation, and the change of the water from a gas to a liquid causes a reduction of volume of the air, which reduces air pressure. The air pressure gradients produce winds that help distribute moisture and cause temperatures to change over the globe.
Locally, the heat affects life directly. The higher the air temperature, the more water it can absorb and hold, and hence the greater is its drying power. In some very large parts of the Earth, those that we generally call deserts, there is almost no rain and what little does fall tends to be episodic. Desiccation created by high temperatures then poses a challenge for plants and animals, especially if they must maintain a body temperature below the temperature of the air and despite the added heat load of solar radiation. In moister regions summer warmth stimulates growth and sunshine provides the energy. But deserts have a surplus of both heat and solar energy and a scarcity of water, and that dearth of water retards or prevents the conversion of the plentiful energy from the sun into the chemical energy useful for life.
Life in deserts confronts hard-edged limits, though often in a context of intense beauty. Life exists there only because of intricate behavioral and physiological adaptations. Field trips into the Mojave and Anza Borrego deserts of southern California opened my eyes to this environment and its exotic animals, which I saw through the lens of work done with George Bartholomew in our lab at my graduate school alma mater, UCLA. “Bart” in turn led me to the research and writings of Knut and Bodil Schmidt-Nielsen, Ray Cowles,