His photos appear frequently in National Geographic magazine ... It's a new world when you get up there. Textbook geology (dry as dust in the classroom) leaps to fascinating life.

His photos appear frequently in National Geographic magazine ... setting my own clock to the time frame of geology, blocking off the rest of the world, and entering into a sort of communion ...

Prehistoric time line, geologic time scale, photos, facts, maps, and more from National Geographic. Humans have walked the Earth for 190,000 years, a mere blip in Earth's 4.5-billion-year history.

This photo was submitted to Your Shot, our photo community on Instagram. Follow us on Instagram at @natgeoyourshot or visit us at natgeo.com/yourshot for the latest ...

This story appears in the January 2018 issue of National Geographic magazine ... who took this photo in the agrarian village of Arbeca, Spain. “Starlings often prefer cities and agricultural ...

Photograph by Joel Sartore, National Geographic Photo Ark The earliest multicelled ... mirroring the bleak endings to the geologic periods that followed.

As the magnitude of water shortage issues arise globally, National Geographic Explorers along with the World Freshwater ...

Photograph by Joel Sartore / National Geographic Just as photography can paint a beautiful picture, it can equally shock people into action. Photos can present graphic evidence of humans ...