About 10,000 years ago we discover farming. But when crops fail, early farming communities face a new threat. War. It's the birth of the arms race.

When ordinary people desire the luxuries of the rich, ingenuity and innovation come together to take history in a new direction. From the obsession with silk to the fall of Constantinople, the discovery of the Americas to the launch of the Industrial Revolution, our desire for luxury has shaped our history and evolution.

Over millions of years mankind has evolved from a puny, vulnerable creature to become a dominant force on the planet. Occasionally the planet bites back--with terrifying consequences that have shaped our evolution.

The world is linked like never before. Modern transport and communications have resulted in a world that is wealthier, healthier, more mobile and better informed than ever before. But throughout history new trade routes have proved to be double-edged swords, opening the way to wealth as well as terrible dangers — among them revolutionary ideas and terrifying pandemics.

Tools and machines have allowed us to overcome our physical limitations, and become the most successful species on Earth. But tools are also transforming what it means to be human.