Geologic Time

Front

What is an animal without a backbone called?

Back

Invertebrate

Front

In which Era were dinosaurs and reptiles dominant?

Back

Mesozoic

Front

What is one of the units of geologic time into which geologists divide eras?

Back

Period

Front

In which era did early vertebrate fish begin to develop?

Back

Paleozoic

Front

Which Era was dominated by dinosaurs?

Back

Mesozoic

Front

What is the term for the scale that geologists use to describe the timing and relationships of events in Earth's history?

Back

Geologic time scale

Front

What is the earliest era in the geologic time scale?

Back

Precambrian

Front

What type of fossil is formed when minerals replace the organic material in an organism?

Back

Petrified fossil

Front

What is the term for a gap in the geologic record?

Back

Unconformity

Front

What era is known for the rise of mammals?

Back

Cenozoic