Sign up for free

Newsletters

Once a month
get new photos
and expert tips.

Science and Space
Main Health and Human Body Earth Space Prehistoric World A-Z

Carboniferous Landscape

Illustration: Prehistoric trees and plants

The Carboniferous period saw the appearance of the first extensive forests on Earth. The growth of these forests removed huge amounts of carbon dioxide from the atmosphere, leading to a surplus of oxygen. Atmospheric oxygen levels peaked around 35 percent, compared to 21 percent today.

Artwork by Mary Evans Picture Library/Alamy