Academic Earth/Space Science : Chapter 13 - Earth's History

Timlin, Block 3

Age of Earth

4\.54 billion years old

Largest time span of Earth’s history

Precambrian

Shields

areas of Precambrian rock exposed at Earth’s surface

Gasses of Earth’s early atmosphere

Water vapor, nitrogen, carbon dioxide

How did these early gasses form?

Volcanic eruptions

Significance of “Red Beds”

They showed when free oxygen was available because the rocks rusted

When did the **first** fossils form?

3\.5 billion years ago

Stromatolites

Most common Precambrian fossils, the houses that were built by cyanobacteria

Order of the Eras

Precambrian, Paleozoic, Mesozoic, Cenozoic

Length of the Paleozoic Era

292 million years

How many million years ago did abundant fossil information become available?

540 million years ago, after the Cambrian life explosion

Which continents make up Gondwana?

South America, Africa, Australia, and India

Which continents make up Laurasia?

North America, Europe, parts of Asia, and Siberia

When did Pangaea form?

End of the Paleozoic

Where was most life found during the Paleozoic?

In oceans or along coastlines

When did coal swamps form?

Carboniferous

When did the “Age of Fishes” occur?

Devonian

How did “hard parts” help animals survive and evolve?

They protected animals from predators and waves, giving them a longer life span and allowing them to reproduce.

What is meant by the “Cambrian explosion” of life

many new organisms evolved rapidly in a relatively short time span, and when most major animal groups appear in the fossil record.

When did Pangaea begin to break apart?

During the Mesozoic

What was the noteworthy tectonic event tool that took place 200 million years ago?

Pangaea began to break up

Which “group” do dinosaurs technically belong to?

They are considered reptiles

Which animals were the first to inhabit the land?

Reptiles

Which animal linked birds to dinosaurs?

Archaeopteryx

What caused the extinction of dinosaurs?

Large meteorite colliding with Earth

What period are we part of?

Quaternary

What causes mountain building?

Collision of two landmasses by plate movement

Which mountains formed during the Cenozoic?

Himalayas, Alps, and the Rockies

Why are Milankovitch cycles considered the cause of Ice Ages?

The ways the Earth spins causes periods of warming and cooling

Mammals

warm-blooded, insulating body hair, adaptations to survive in cold regions

Reptiles

cold-blooded, no insulating body hair, no adaptations to survive in cold temperatures

When did Mammals become the dominant land animals?

After the extinction of dinosaurs