Simplify the following text for a Grade 8 native English-speaking person.
Original: Because the Iapetus Ocean was positioned between continental masses that would at a much later time roughly form the opposite shores of the Atlantic Ocean , it can be seen as a sort of precursor of the Atlantic .
Simplified: The Iapetus Ocean was positioned between continental masses that would at a much later time roughly form the opposite shores of the Atlantic Ocean . It was a kind of precursor of the Atlantic .