The human body is 70% water. The surface of the earth is 70% water. It is THE most important substance for making life possible. Learn about insightful ideas for using water, keeping it clean and getting it where people need it.
Azzizia Desalination Plant in Saudi Arabia. (Waleed Alzuhair/Flickr)
The lemon shark's yellow coloring serves as a camouflage when swimming over the sandy seafloor in its coastal habitat. (Creative Commons)