Okay. So were you asking where they were? How many there were? Who all they cover? Or was that all?
In the later areas of the game (starting in the Wildlife Exploitation Preserve), there are 4 Echos per main character that explains why they're on Pandora. Maya's was the most interesting, in my opinion.
"Do you remember the episode where Ash caught a Pumbloom?" "Dude!--" "NOOOOOOOOOOOOOOOO!"