Which was critical in the evolution of reptiles to be able to adapt to many terrestrial ecosystems?

Oldest Earth material:

Another name for far-traveled microcontinents

What adaptation evolves to help trilobites avoid predators?

The Oklahoma and Marathon Mountains are erosional remains of the ___________ orogen

Age of rocks containing significant numbers of large dragonflies.

When do invertebrates with hard parts suddenly appear in the fossil record?

What type of equipment artifact has no specific pattern and ranges from minor to severe?

A cratonic sequence of strata is recognized by:

Were would be a good place in North America to look for Precambrian-aged rocks exposed on the surface?