Pennsylvanian

Other forms: Pennsylvanians

The Pennsylvanian period of the Paleozoic era lasted from about 323 to 299 million years ago. Often called the "Age of Coal," the Pennsylvanian was a time of dense, swampy forests and giant insects.

During the Pennsylvanian, giant tree-like plants (called scale trees), horsetails, and tree ferns grew in lush coastal swamps and eventually decayed to form massive coal deposits. Giant arthropods, including dragonfly-like insects with wingspans of nearly 2.5 feet and millipedes up to 8 feet long, thrived, as did amphibians. The first true reptiles appeared, able to live and breed entirely on land. The period also saw glacial cycles, especially in the southern hemisphere. This period is known as the Upper Carboniferous in Europe.

Definitions of Pennsylvanian

1. noun

   a native or resident of Pennsylvania
   synonyms: Keystone Stater

   type of:

   American

   a native or inhabitant of the United States
2. adjective

   relating to or denoting the period from about 323 to 299 million years ago
3. noun

   the period of geologic time from about 323 to 299 million years ago; the sixth period of the Paleozoic era
   synonyms: Pennsylvanian period, Upper Carboniferous, Upper Carboniferous period

   example of:

   geological period, period

   a unit of geological time during which a system of rocks formed