We're crossing a land bridge for the Geo Quiz. The isthmus we'd like you to name was formed during a major geological event some three million years ago and it was once known as the Isthmus of Darien. The country there now, is not only a land bridge between North and South America, it also offers a "water bridge," so to speak, between the Pacific Ocean and the Caribbean Sea.
It's a major commercial portal. These days, there's big time construction going on there — to widen the waterway. And geologists are having a field day digging up rocks that are millions of years old and collecting precious information about prehistoric times in the area.
So, where are we?
Answer: The Isthmus of Panama. The World's intern Satenik Karapetyan reports on paleontologists studying rocks collected during ongoing excavation work on the Panama canal, which is being expanded. They say these rocks will help explain the geological history of the isthmus.