quaternary period
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Definition
Proper noun The Quaternary Period is the current and most recent geological period within the Cenozoic Era, spanning approximately the last 2.6 million years to the present. It is characterized by repeated glacial cycles (ice ages) and the evolution and dominance of humans (Homo sapiens).
Usage
The term "Quaternary Period" is used in geological, climatological, and archaeological contexts to denote the specific timeframe of Earth's history defined above. - It is typically capitalized as it is a formal, proper name for a geological time unit. - It is often discussed in relation to its two subdivisions: the Pleistocene and Holocene epochs.
Examples
- Noun:
- The Quaternary Period is noted for its dramatic climatic fluctuations.
- Many large mammals, known as megafauna, went extinct during the Quaternary Period.
- Human civilization developed entirely within the later stages of the Quaternary Period.
Advanced Usage
- "The Quaternary": Often used as a shortened form to refer to the Quaternary Period.
- Sea levels have varied greatly throughout the Quaternary.
- In formal stratigraphy, it is sometimes referred to as the Quaternary System when referring to the rock layers deposited during this time.
Variants and Related Words
- Quaternary (adj/n): Relating to or denoting the Quaternary Period. As a noun, it is the shortened form.
- Quaternary climate change; sediments from the Quaternary.
- Pleistocene Epoch (n): The first and longer epoch of the Quaternary, from about 2.6 million to 11,700 years ago, known as the "Ice Age."
- Holocene Epoch (n): The current epoch of the Quaternary, beginning about 11,700 years ago after the last major ice age.
Synonyms
- Age of Man: An informal term highlighting the rise of humans.
- Recent Period: A descriptive synonym emphasizing its geological recency.
Related Phrases
- Quaternary glaciation: The cycle of glacial and interglacial periods during this period.
- Quaternary science: The interdisciplinary study of this period, encompassing geology, archaeology, and paleoclimatology.
Noun
- last 2 million years