The evolution of the EarthCredit: NASA/Johnson Space Center
Earth formsCredit: University of Copenhagen, Lars A. Buchhave
Boom! Earth-Moon collisionCredit: NASA/JPL-Caltech
Magma oceanCredit: Diego Barucco/Shutterstock
First continentsCredit: Jacques Descloitres, MODIS Land Rapid Response Team, NASA/GSFC
Breath of lifeCredit: Rob Bayer/Shutterstock
SupercontinentsCredit: Nicolle Rager, National Science Foundation, based on Pangaea map data, Paleogeographic Atlas Project, University of Chicago
Big chillCredit: Snowball Earth image via Shutterstock
Life explodesCredit: Katrina Kenny & Nobumichi Tamura
Mass extinctionsCredit: Rainer Albiez/Shutterstock
Ice agesCredit: Photo by Jonathan S. Blair/National Geographic
The Plasticene?Credit: Patricia Corcoran.
USDA Fed Cats and Dogs to Kittens, Alarming Watchdog Report Claims
2,500 Years Ago, Herodotus Described a Weird Ship. Now, Archaeologists Have Found it.
Incredible Photos Capture Last Glimpse of Long-Tusked 'Elephant Queen'
What's Behind the Massive Midwestern Floods: 2 Giant Waves of Water
Traces of Infamous Nazi Massacre Unearthed in Germany