A fossil is________.

What type of fossil is displayed?

Fossils usually form in which type of rock?

Which type of fossil is displayed?

A fossil formed when minerals replace all or part of an organism is called a _____.

Which type of fossil is displayed?

____ can provide clues about the activities of ancient organisms.

The _________________________Era is sometimes referred to as the “Age of Reptiles.”

The process by which all the different kinds of living things have changed over long periods of time is called _____.

A type of organism that no longer exists on Earth is known to be_________.

The present day is part of the ____________era.

Geologic time begins with the span of time known as the _______________ Time.

The law of superposition states that__________.

The fossils of organisms that were widely distributed but only lived during a short period of time are called________.

The Paleozoic, Mesozoic, and Cenozoic are divisions in the geological time scale called__________.

The geologic time scale is a record of_________.

Certain ammonites are used as____________ fossils because they lived in many different areas but only for a brief time.

___________ are scientists who study fossils.

A(an)__________fossil forms when dissolved minerals replace all or some of an organism and then harden to form rock.

The earliest life forms were___________.

Many scientists hypothesize that the dinosaurs became extinct because____________.

The evolution of photosynthetic organisms about 2.5 billion years ago led to_________.

The end of the Paleozoic was marked by the___________.