What is the Cambrian Explosion?
What is sediment?
What is Relative age?
What is Sedimentary Rock?
What is a Paleontologist?
What is the Paleozoic Era?
What is a Petrified Fossil?
What is the Cenozoic Era?
What is the Mesozoic Era?
What is the Paleozoic Era?
What is Evolution?
What is a mass extinction?
What is the Half-Life?
What is the Mesozoic Era?
What is the Law of Superposition?
What is the Precambrian time?
What are periods?
What are Invertebrates?
What are Igneous rocks?
What is an Intrusion?
What are vertebrates?
What is Carbon-14?
What is Radioactive Dating?
What is Relative age?
What are Amphibians?
Reptiles evolved from
This era is often called the Age of the Reptile
Magma that forces its way into rocks and hardens is called an
The time for half of the radioactive atoms to decay in a radioactive element
When a mineral REPLACES all or parts of an organism it is called a
Radioactive dating is used for this type of rock
Plants and animals first reached land during this Era
This radioactive material is used to date rocks that lived up to about 50,000 years ago
Animals without backbones are called
Fossils are almost always found in what kind of rock?
The law of superposition is use to determine what type of age for rocks
A great number of different organisms evolved during this event
This event occurred at the end of the Cretaceous period
Most fossils form when organism die and are buried in
This law states that in horizontal layers of sedimentary rock the oldest rock is on the bottom
Humans first appeared at the END of what Era?
A scientist who studies fossils is called an
To determine the Absolute age of rocks scientist use
An animal with a backbone is called a
Dinosaurs ruled the Earth during what Era?
Pangaea formed at the END of what era?
On the geologice time scale, eras are divided into
The earliest form of life appeared during
Index Fossils are useful because they can tell what type of age of the rock
The process by which all the different kinds of living things have changed over long periods of time is called