Book excerpt: Four people are born every second of every day. Conservative estimates suggest that there will be 10 billion people on Earth by 2050. That is billions more than the natural resources of our planet can sustain without big changes in how we use and manage them. So what happens when vast population growth endangers the world’s food supplies? Or our water? Our energy needs, climate, or environment? Or the planet’s biodiversity? What happens if some or all of these become critical at once? Just what is our future? In Tipping Point for Planet Earth, world-renowned scientists Anthony Barnosky and Elizabeth Hadly explain the growing threats to humanity as the planet edges toward resource wars for remaining space, food, oil, and water. And as they show, these wars are not the nightmares of a dystopian future, but are already happening today. Finally, they ask: at what point will inaction lead to the break-up of the intricate workings of the global society? The planet is in danger now, but the solutions, as Barnosky and Hadly show, are still available. We still have the chance to avoid the tipping point and to make the future better. But this window of opportunity will shut within ten to twenty years. Tipping Point for Planet Earth is the wake-up call we need.