1.Which one lived in Antarctica earlier, the labyrinthodont, the lystrosaurus, or the duck-billed dinosaur? Explain

The correct answer is - The labyrinthodont.

Explanation:

Fossils of These duck billed dinosaur were found in the Antarctica in sands that were 66 to 67 million years old, however these are also found in north America and north Europe.

About 110 million years ago, labyrinthodonts, the dinosaur that are amphibians. These are the animals that were lived in the river valleys of the Gondwana and the rift valley that was located at that time between Australia and Antarctica.

Thus, the correct answer is - The labyrinthodont.