Carboniferous Period

An age of expansive coal swamps

The Carboniferous Period (359-299 Ma) is in the Paleozoic Era, occurring after the Devonian Period and before the Permian Period.

Geologic Age

  • 359.2–299.0 million years ago

Eon / Era


Pennsylvanian: 323.2–298.9 Ma

  • Late Pennsylvanian: 307.0–298.9 Ma

  • Middle Pennsylvanian: 315.2–307.0 Ma

  • Early Pennsylvanian: 323.2–315.5 Ma

Mississippian: 358.9–323.2 Ma

  • Late Mississippian:

  • Middle Mississippian

    • Visean: 346.7±0.4–330.9±0.3 Ma

  • Early Mississippian

What happened during this time?



  • Lycophytes

  • Ferns and horsetails

  • The progymnosperms, such as Archaeopteris, the Stenokoleales, and the Noeggerathians are on the landscape, but only the latter group survives after the Carboniferous

  • There is a diversification of seed plants during the Carboniferous

  • Origin of swamp and forest systems

    • During this time, the vast swamps of scale trees, ferns, horsetails, and seed ferns created most of the coal that we use for energy today

    • These plants grew and decayed in these environments, but some biological or environmental factors inhibited the amount of complete decay of plant material, resulting in massive amounts of coal being created during this time

    • The "evolutionary lag hypothesis", claims that fungi had not evolved the ability to degrade lignin, a chemical that makes wood tough and resistant

    • Evidence from Nelsen et al. (2015), claims that there were most probably lignin-degrading organisms around during the Carboniferous, and the abundance of coal during this time was "likely the result of a unique combination of everwet tropical conditions and extensive depositional systems" with massive amounts of plant material being dropped in these humid environments.


    • Winged insects; plant herbivory

    • Diversification of amphibians

    • Reptiles appear, with Hylonomus from 312 Ma

    • A group called diadectids, appear during Carboniferous and were the first herbivorous tetrapods


  • Mean oxygen levels in the atmosphere: 31.5%

  • Mean carbon dioxide levels in the atmosphere: 1,300 ppm

Above: Reconstruction of Hylonomus lyelli