Air date: 2006-10-31

Runtime: 90 min

From microscopic bacteria to the largest animals, this installment explores the incredible biodiversity of the Earth, highlighting the interdependence of the planet's inhabitants.

Air date: 2007-01-04

Runtime: 90 min

Discover why fresh water is the most precious resource on Earth, vital to life and prosperity, but is also one of the most threatened, with spectacular scenery of canyons, glaciers and waterfalls, as well as man-made structures.

Air date: 2007-04-17

Runtime: 90 min

Covering 72 percent of the planet, the sea is an extensive, but not inexhaustible, resource. This episode sheds light on how to protect it and explores humankind's interdependence with the sea.

Air date: 2007-07-05

Runtime: 90 min

As man's impact on Earth reaches an all-time high, meet innovators who are attempting to reverse the damage and write a new contract with nature. In scenes across the globe from America to China, this exploration of man's influence on the Earth also includes discussion on how to lighten it.