Quiz 8 Geol

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What period is when life on Earth began to flourish?

A Brief History of Earth Early life forms began to flourish during the Cambrian Explosion, 540 million years ago.

Which era of geologic time spans about 88 percent of Earth’s history?

Precambrian time covers about 88 percent of Earth’s history, from 4.6 billion years ago to 541 million years ago. Few fossils survive from this time period.

Which period is known as the Age of Fishes quizlet?

Devonian Period. New Fact: Started about 416 million years ago.

What is the most common Precambrian fossil?

The most common Precambrian fossils are stromatolites. Stromatolites are distinctively layered mounds or columns of calcium carbonate.

What era are we currently in?

Our current era is the Cenozoic, which is itself broken down into three periods. We live in the most recent period, the Quaternary, which is then broken down into two epochs: the current Holocene, and the previous Pleistocene, which ended 11,700 years ago.

What are the periods of life on Earth?

It is subdivided into three eras, the Paleozoic, Mesozoic and Cenozoic, which are divided by major mass extinctions.

• Palaeozoic Era.
• Mesozoic Era.
• Cenozoic Era.

How will you classify periods into era?

Eons are divided into smaller time intervals known as eras. In the time scale above you can see that the Phanerozoic is divided into three eras: Cenozoic, Mesozoic and Paleozoic. Very significant events in Earth’s history are used to determine the boundaries of the eras.

How many eras are there in Earth’s history?

There are three Geologic Eras currently identified. The Paleozoic Era, the Mesozoic Era, and the Cenozoic Era. See illustration at right. Each of the names of the Eras reflects the relative stage in the development of life.

Which era takes up most of Earth’s history?

Take the Precambrian Era. It lasted more than 4 billion years — or for more than 90 percent of Earth’s history.

Which era is sometimes called the Age of dinosaurs which era is sometimes called the Age of dinosaurs?

During the Mesozoic, or “Middle Life” era, life diversified rapidly and giant reptiles, dinosaurs and other monstrous beasts roamed the Earth. The period, which spans from about 252 million years ago to about 66 million years ago, was also known as the age of reptiles or the age of dinosaurs.

Which era is sometimes called the Age of fish?

The Devonian, part of the Paleozoic era, is otherwise known as the Age of Fishes, as it spawned a remarkable variety of fish. The most formidable of them were the armored placoderms, a group that first appeared during the Silurian with powerful jaws lined with bladelike plates that acted as teeth.

What era is sometimes called the Age of dinosaurs?

The Mesozoic Era is literally the era of “middle life.” It is also known as the age of dinosaurs. It lasted from 245 to 65 million years ago and is divided into the three periods described inFigure below. The Mesozoic began with the supercontinent Pangaea.

In what era can the oldest?

The oldest is the Paleozoic Era, which means “ancient life.” Fossils from the Paleozoic Era include animals and plants that are entirely extinct (e.g., trilobites) or are rare (e.g., brachiopods) in the modern world.

Is Fern an index fossil?

Even fossils of tropical plants such as ferns, cycads etc are being found in the Arctic island, Spitsbergen. Thus, the presence of index fossils leads to the verification of the theory of Continental Drift.

Which era is known as the Age of Reptiles?

Assorted parareptiles occurred throughout the Permian Period (299 million to 251 million years ago), but they largely disappeared from the fossil record by the beginning of what was to become known as the “Age of Reptiles,” the Mesozoic Era (251 million to 65.5 million years ago).