Biology (B)

Lesson Objectives

• Know that geologists and paleontologists use evidence to determine the history of Earth and life on Earth.
• Know that geologists and paleontologists measure the radioactivity in certain rocks to determine the age of the earth and fossils.
• Know that the earth is between four and five billion years old.
• Know that scientists need to know what the environment (what chemicals were around, the temperature, etc.) was like on Earth billions of years ago to know how life formed.