Front

What is the shortest unit of geologic time?

Back

An epoch.

Front

What is the longest unit of geologic time?

Back

An eon.

Front

Where are strata mostly found?

Back

Underground.

Front

When can the first evidence of life on Earth be traced back to?

Back

About 3.8 billion years ago.

Front

True or False: Most organisms become preserved in rock as fossils.

Back

False.

Front

What are fossils?

Back

Fossils are the preserved remains or traces of ancient organisms.

Front

What is the geologic time scale?

Back

A system of chronological dating that relates geological strata to time.

Front

What is an era in geologic time?

Back

A major division of geologic time, consisting of multiple periods.

Front

What is a period in the geologic time scale?

Back

A subdivision of an era, marked by significant geological or paleontological events.

Front

What is the significance of the Cambrian period?

Back

It marks the beginning of the Paleozoic era and the rapid diversification of life.