Devonian Period

Geological Overview

The Devonian period is part of the Paleozoic era and is divided into Early, Middle, and Late epochs. It is often considered the "Age of Fishes" due to the diverse array of fish species that evolved during this time.

Climate and Geography

During the Devonian period, the Earth's landmasses were part of the supercontinent Gondwana and Euramerica. The climate was generally warm, and there were no polar ice caps. The first forests consisting of early vascular plants emerged during this time.

Biological Events

• Evolution of Fish: The Devonian saw the diversification of fish, including the appearance of the first jawed fish and the rise of placoderms, an extinct group of armored fish.
• Terrestrialization: Some fish evolved adaptations that allowed them to venture onto land, marking the early stages of terrestrial life.
• Plants and Invertebrates: The first forests emerged, composed of primitive plants such as ferns and early seed-bearing plants. Invertebrates, including arthropods and early tetrapods, also began to colonize the land.

Mass Extinction

The end of the Devonian period was marked by a significant mass extinction event, which affected marine and terrestrial organisms. It is believed that a combination of climate change, sea-level fluctuations, and possibly asteroid impacts contributed to this extinction event.

Study Tips

1. Understand the geological and climatic conditions of the Devonian period and how they influenced the evolution of life.
2. Study the key evolutionary developments in fish, plants, and invertebrates during this period.
3. Explore the factors that may have contributed to the Devonian mass extinction event and its impacts on life forms.
4. Compare and contrast the Devonian period with earlier and later epochs to understand the broader trends in Earth's history.

[Devonian] Related Worksheets and Study Guides:

• Geologic timeScience • Eighth Grade