Earth's Systems
- Climate
A dire shortage of water
Parts of the southwestern United States are in the middle of the worst drought in at least 500 years.
- Earth
Distant quake changes geyser eruptions
An Alaskan earthquake changed the timing of geysers thousands of miles away.
- Humans
A human migration fueled by dung?
When people crossed from Asia to the Americas thousands of years ago, burning dung may have kept them warm.
