devonian period
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Definition
- Proper noun:
- A geological period: The Devonian Period is a specific interval of geological time within the Paleozoic Era, occurring approximately from 419.2 million to 358.9 million years ago. It is characterized by significant diversification of fish and the first appearance of amphibians and ammonites on Earth.
Examples of Usage
- Proper noun:
- The Devonian Period is often called the "Age of Fishes."
- Many important fossil deposits date back to the Devonian Period.
- The first forests appeared on land during the Devonian Period.
Advanced Usage
- "the Devonian": A common shorthand term for the Devonian Period.
- The rocks from the Devonian contain abundant marine fossils.
Variants and Related Words
- Devonian (adj): Relating to the Devonian Period.
- Devonian rocks are found in many parts of the world.
- Late/ Early/ Middle Devonian (noun phrases): Subdivisions of the Devonian Period.
- The first amphibians evolved in the Late Devonian.
Synonyms
- Age of Fishes: An informal name for the Devonian Period, highlighting its key biological feature.
Related Phrases
- Devonian extinction: Refers to a series of extinction events that occurred near the end of the Devonian Period.
- The Devonian extinction affected many marine species.
Noun
- from 405 million to 345 million years ago; preponderance of fishes and appearance of amphibians and ammonites