This blog’s mantra is that the core and most important problem civilization faces is that “too many people consume, and have been consuming, too much” for our familiar Earth to sustain. Harnessing energy sources for human use has been man’s hallmark since our species emerged some 150,000 years ago, a truth illustrated by an exhibit at one of Dallas’s cultural gems, the Perot Museum of Nature and Science.
The Perot exhibit estimates energy consumption 100,000 years ago as the equivalent of 1/5 of a gallon on gasoline per person per day, and energy consumption today as the equivalent of six gallons of gasoline per person per day. We are now over seven billion energy consumers as opposed to the few thousand hunter-gatherers alive 100,000 years ago, and intense energy use is one measure of a modern economy’s success. Human progress and growth in gross national product (GNP) are too often treated as equivalent, and higher GNP usually involves more energy consumption. Man with his numbers and his tools now dominates the planet, and we consciously shape our own environments in our homes, our work and in our play using energy sources we mine from the Earth.
We also, mostly unconsciously, shape the natural systems which support all life on Earth, including our own. Our civilization uses massive amounts of energy to produce and to operate the tools – roads, cars, medical care and so forth – which help make life as pleasant as it is. Much of the energy we use is from burning hydrocarbons – coal, oil and gas – which have energy concentrated and stored by plants and animals which lived millions of years ago. Burning huge amounts of fossilized carbon produces chemical byproducts, most prominently carbon dioxide, whose atmospheric abundance has increased over 40 percent since we began using coal to power machines 250 years ago. We have treated Earth’s thin layer of air as a garbage dump for our wastes from energy consumption, and the unintended, dangerous consequences include global warming and ocean acidification.
There are probably billions of planets within our Milky Way galaxy that support life in some form, given what the astronomers, chemists and physicists have told us recently. On Earth, the path of life through countless species has generally been towards greater intelligence and greater mastery of a creature’s natural environment. Homo sapiens has rapidly altered land, air and water since our species emerged and then multiplied and created newer, more complex tools that made us and our ancestors more dominant and more comfortable. It’s reasonable to believe life has taken similar paths in alien worlds in our Universe which science can now only dimly see and speculate about. The unresolved issue is whether evolution of life forms using sophisticated technology most often, or even necessarily, produces fowling of the technology creators’ home nest which kills them. That is one pessimistic explanation for interstellar silence; so far we have no radio programs from faraway planets. Scientists are listening intently for conversations from intelligent life out there; our prayer should be that sophisticated, benevolent extraterrestrials exist and that messages from them will come, and soon, to help us reconcile our complex, energy-intensive technology with our own long-term survival.