A group of animals that breed together

Where an organism survives based on traits, AKA survival of the fittest

Paleozoic, Mesozoic, and Cenozoic are classified as _________

Longest part of Earth's history, lasting from 4 billion to about 544 million years ago.

A break or gap in the sequence of a series of rock layers due to erosion

List the expanses of time in the Geologic Time Scale in order from longest to shortest

In what time do we currently live?

Name the first organism to appear on Earth

This fossil lived in many different places on Earth but only for a short period of time

Process in which some atoms or isotopes break down into other isotopes & particles

The age of something when compared with the position of different rock layers

Radioactive decay of material can be used to determine the age of fossils. This is called ____________

The half life of Carbon 14 is ____________

Scientific Law that states the youngest sedimentary rock layer is found on top is called _______________?

How many half-lives have passed if a rock has 25% Carbon 14?

Principle that states "the present is key to the past"

Which Era is considered 'middle life' and the 'Age of reptiles'?

In which Era did flowering plants appear?

In which Era did Pangaea separate?

Second longest division of geo time, based on major worldwide changes in types of fossils

Era of "Ancient Life", "Age of Invertebrates", organisms developed hard body parts

Remains, imprints, or traces of prehistoric organisms that are usually preserved in sedimentary rock