All of the easy oil is gone and what's left is requiring more energy and money and this has an effect on everything. Our problem is that we've created an infrastructure that's so dependent on oil. As oil becomes more expensive we're going to be locked into the transportation modes that our economy depends on. So we really need to start building an alternative economy before we get caught in a trap of our own making.

Today, it is especially difficult for most people to understand our perilous global energy situation precisely because it has never been more important to do so.

When a caterpillar eats a leaf, then a thrush eats the caterpillar, or when a hawk eats the thrush only 5 to 20% of usable energy is transferred from one level to the next. ... Thus herbivores will account for a much smaller fraction of the biomass [than plants] and the carnivores for a still smaller fraction.

...the era of cheap oil and natural gas is coming to a crashing end, with global oil production projected to peak in 2010 and North American natural gas extraction rates already in decline. These events will have enormous implications for America's petroleum-dependent food system

The science is in: either we go cold turkey on our coal, oil, and gas addictions, or we risk raising the planet's temperature to a level incompatible with the continued existence of civilization.

Early ecologists soon realised that, since humans are organisms, ecology should include the study of the relationship between humans and the rest of the biosphere. ... We don't often tend to think about the social sciences (history, economics and politics) as subcategories of ecology. But since people are organisms, it is apparent that we must first understand the principles of ecology if we are to make sense of the events in the human world.

If we do nothing, we still get to a post-carbon future, but it will be bleak. However, if we plan the transition, we can have a world that supports robust communities of healthy, creative people and ecosystems with millions of other species.