Simplify the following text for a Grade 10 native English-speaking person.
Original: Lessepsian migration ( also called Erythrean invasion ) is the ongoing migration of marine species across the Suez Canal , usually from the Red Sea to the Mediterranean Sea , more rarely in the opposite direction .
Simplified: Lessepsian migration is the name given for the migration of marine species through the Suez Canal , between the Red Sea and the Mediterranean .