Question
Forming a Supercontinent
Scientists use data from fossils, rocks and other land formations to better understand how Earth has changed over time. They have analyzed evidence to understand how the supercontinent Pangaea became the continents known today. The diagram shows Pangaea (Pangea).

The continents and subcontinents are on different tectonic plates that move slowly over time. Adjacent plates move along the plate boundaries, or edges. Divergent boundaries occur when two plates move away from each other. Convergent boundaries occur when plates move toward each other. These boundaries are predicted to be the cause of the physical features that are observed today, and how the continents came to exist. Similar physical features and rock formations can be found on continents that are now separated by oceans. The diagram shows the different plates on Earth.

Similar fossils have also been found on different continents. The table shows where three of these fossils were found.
SpeciesRelative age of Rocks (millions of years ago)LocationCynognathus200 myaSouth America, AfricaGlossopteris300 myaSouth America, India, Australia, Antarctica, AfricaLystrosaurus300 myaAfrica, India, Antartica
Multiple Choice Question
The Appalachian Mountains and the Caledonian Mountains are similar in age and composition. What does this suggest about the continents on which they are found?
A.
They likely were formed after they moved apart.
B.
They both experienced the same past climate changes.
C.
They were once farther away and are moving closer together.
D.
They were likely joined and moved apart due to plate motions.
Scientists use data from fossils, rocks and other land formations to better understand how Earth has changed over time. They have analyzed evidence to understand how the supercontinent Pangaea became the continents known today. The diagram shows Pangaea (Pangea).

The continents and subcontinents are on different tectonic plates that move slowly over time. Adjacent plates move along the plate boundaries, or edges. Divergent boundaries occur when two plates move away from each other. Convergent boundaries occur when plates move toward each other. These boundaries are predicted to be the cause of the physical features that are observed today, and how the continents came to exist. Similar physical features and rock formations can be found on continents that are now separated by oceans. The diagram shows the different plates on Earth.

Similar fossils have also been found on different continents. The table shows where three of these fossils were found.
SpeciesRelative age of Rocks (millions of years ago)LocationCynognathus200 myaSouth America, AfricaGlossopteris300 myaSouth America, India, Australia, Antarctica, AfricaLystrosaurus300 myaAfrica, India, Antartica
Multiple Choice Question
The Appalachian Mountains and the Caledonian Mountains are similar in age and composition. What does this suggest about the continents on which they are found?
A.
They likely were formed after they moved apart.
B.
They both experienced the same past climate changes.
C.
They were once farther away and are moving closer together.
D.
They were likely joined and moved apart due to plate motions.
Answers
GPT-5 mini
D. They were likely joined and moved apart due to plate motions.
Reason: Mountains with the same age and rock types on different continents indicate they formed in the same tectonic event when those landmasses were connected; later plate motion separated them. Options A, B, and C do not explain matching age and composition as directly as past connection and later rifting.
Reason: Mountains with the same age and rock types on different continents indicate they formed in the same tectonic event when those landmasses were connected; later plate motion separated them. Options A, B, and C do not explain matching age and composition as directly as past connection and later rifting.