Happenings During the Paleozoic Era (545-248 Million Years Ago)

Time:

Geography:

  • Earth’s tectonic plates were on the move during the Paleozoic! By the end of this time they had moved so much that all of the continents were pushed together making one large continent called Pangaea.

Climate:

  • 430 million years ago glaciers formed and ice covered the northern part of Africa. This area is a desert today, but back then it was located at the South Pole!
  • Climate models have been used to understand the past weather patterns and climates of Pangaea. The models suggest that rainstorms called monsoons affected the East coast and that interior of continent was very dry.

Evolutionary Events:

  • A large number of animals evolved between 530 and 520 million years ago including trilobites and brachiopods (pictured at left).
  • During the early and middle parts of the Paleozoic, most animals lived in oceans. Animals without backbones (such as corals, brachiopods, mollusks, and trilobites) were very common.
  • Animals with backbones (including fish, amphibians, and reptiles) began to flourish in the later Paleozoic. Animals and plants populated the land.
  • About 250 million years ago, almost all of the species in the oceans became extinct. They didn’t die all at once. It took over 8 million years for the mass extinction to wipe them out.
  • About 440 million years ago the Late Ordovician Mass Extinction was the second largest mass extinction of all time. Over 10 million years, many small marine species became extinct including those that built reefs.



Last modified June 1, 2005 by Lisa Gardiner.

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Plate Tectonics

Many forces change the surface of the Earth over time. The largest force that changes our planet's surface is movement of Earth's outer layer in a process called plate tectonics. As shown in this picture,...more

Paleozoic "Sediment Curve" Provides New Tool for Tracking Sea-floor Sediment Movements

Geologists have been studying a new way to learn where sedimentary rocks formed during the Paleozoic Era. Balil Haq, a marine biologist, explains that scientists are using something called a sediment curve...more

What’s That Mineral?

Spotting minerals is fun! There are many different types of minerals. Each has a different name and special traits. You can learn more about minerals by looking closely at them to understand their special...more

Quartz

This mineral is called quartz! Sometimes it looks white like milk but usually it looks clear like glass, sometimes with a little pink or gray tinge of color. You can find crystals of quartz in many different...more

Mica Minerals

Mica minerals make some rocks sparkle! Look for them in your igneous and metamorphic rocks. Do they make your rocks sparkle? They break into flat plates because they have cleavage. ...more

Feldspar

This is a feldspar mineral! Look for it in igneous rocks where it looks like white or pink crystals. You might find it in other types of rocks as well. ...more

Olivine

The mineral that is green is called olivine! Look for it in igneous and metamorphic rocks. In this picture, olivine is filling a hole in the igneous rock. ...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA