This law of geology states that fossils buried below other fossils must be older.
What is the Law of Superposition?
100
This Supereon lasted from Earth's formation until 540 million years ago.
What is the Precambrian?
100
These small, bony structures in the skull can give paleontologists a clue as to what a dead organism ate.
What are teeth?
100
A dead organism quickly must be covered by these in order to become a fossil.
What are sediments?
200
A kind of dating where geologists seek to discover if a fossil is older or younger than another fossil, rather than its actual age.
What is relative dating?
200
4.6 billion years.
What is Earth's age?
200
Impressions of these in the rocks surrounding Archaeopteryx provided a "missing link" in the fossil record between birds and dinosaurs.
What are feathers?
200
Fossils are found in this kind of rock.
What is sedimentary rock?
300
A kind of dating where geologists seek to discover the approximate age of a fossil.
What is numerical dating?
300
The end of this era was marked by the greatest extinction event of all time.
What is the Paleozoic Era?
300
These long, thin structures are evidence that an organism was capable of flight.
What are wings?
300
Because there are so many opportunities for the remains of organisms to be destroyed, this is the approximate percentage of organisms that eventually become fossils.
What is less than 10%?
400
A numerical dating method used by geologists where they analyze a fossil or a rock's chemical composition to determine its approximate age.
What is radiometric dating?
400
The Era where the first humans evolved.
What is the Cenozoic era?
400
These bony structures could be used as evidence that an organism once walked on land.
What are legs?
400
If sediments leak into a mold and harden into a fossil, then you are left with this type of fossil.
What is a cast?
500
It takes 704 million years for half of this kind of radioactive molecule to decay into lead.
What is uranium?
500
This catastrophic event that occurred 252.28 mya nearly wiped out all life on Earth.
What is the Permian Mass Extinction?
500
This is a word for an educated guess, where people use evidence to support an idea of what something was like in the past.
What is an inference?
500
This process of fossilization literally turns an organism to stone.