Geologic Time Line

Plate tectonics may affect changes in species because movement of plates causes a change in:

On the GTS, where did life first appear on Earth?

Theoretically, how old is the Earth?

How does the Geologic Time Scale describe the early Earth?

The Paleozoic Era ended in what possible event that caused 95% mass extinction of marine life?

What is the Geologic Time Scale?

In GTS, the first living organism in the fossil record is called

The largest divisions in geologic time are ______.

As __ evolved, they grew into stromatolites and changed Earth’s atmosphere by producing oxygen:

The Hadean, Archean and Proterozoic Eons are usually grouped into a 'super eon' called the:

The first vertebrates were fish. In which period did they first appear?

Precambrian time began with __________.

As climates changed, organisms that could adapt survived, others became extinct:

What is the current geologic era called?

Where are most of the events along the geologic timeline?

The oldest rock on Earth formed during the _______________.

What three fossils would be representative of the Devonian Period?

The trilobite is considered to be the most famous:

The end of most Eras are marked by a major catastrophe causing mass ____________.

During which geologic period did earliest reptiles and the great coal-forming forests exist?

Geologic time is divided into units based on ______.

According to the table, which geologic time period occurred more than 800 million years ago?