Page 139 - Science Course 3 (Book 2)

Mo11-L5b: Fossil Evidence About Paleozoic Era

Let’s Begin During the Late Paleozoic, dense, tropical forests
grew in swamps along shallow inland seas.

When trees and other plants died, they sank into the
Middle Paleozoic swamps.

The Carboniferous and Permian periods make up the A coal swamp is an oxygen-poor environment where,
Late Paleozoic. over time, plant material changes into coal.

A supercontinent is an ancient landmass which
separated into present-day continents.

By the end of the Paleozoic era, Earth’s continents
Carboniferous Period Permian Period had formed Pangaea—a giant supercontinent.
359 – 299 mya 299 – 251 mya

Late Paleozoic

In the Late Paleozoic, some f shlike organisms
spent part of their lives on land.

Amphibians were so common in the Late
Paleozoic that this time is known as the
age of amphibians.

Ancient amphibians
adapted to land with
lungs, thick skin, and
strong limbs.

Key Concept As Pangaea formed, coal swamps dried up and
Earth’s climate became cooler and drier.
Fossil Evidence About Paleozoic Era
The largest mass extinction in Earth’s history, called
How did the organisms adapt to land? the Permian mass extinction, occurred at the end of
the Paleozoic era.

Fossil evidence indicates that 95 percent of marine
life-forms and 70 percent of all life on land became
extinct.

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