Fossils and Evolution

Front

How do fossils form?

Back

An organism is rapidly buried. The sediments and minerals replace the tissues.

Front

One of the oldest organisms discovered is called a(n) _________.

Back

trilobite

Front

What determines the relative age of fossils?

Back

Index Fossils and Law of Superposition.

Front

What does it indicate if fossils of fish are found under land where cows now live?

Back

This land was once under the ocean.

Front

What are structures that share a common ancestor but have different functions called?

Back

homologous structures.

Front

What is the term for fossils that are used to determine the age of rock layers?

Back

Index fossils.

Front

What is the process called when minerals replace the organic material in an organism?

Back

Petrification.

Front

What type of fossil forms when an organism leaves an imprint in sediment?

Back

Cast and mold fossil.

Front

What is the significance of the Law of Superposition in geology?

Back

It states that in undisturbed rock layers, the oldest layers are at the bottom.

Front

What are vestigial structures?

Back

Structures that have lost their original function through evolution.