How do you use team skills in fossil fighters

If you put a certain combination of vivosaurs on your fighting team (the 3 that actually go into battle in a fossil battle), their medals will flash and gleam. That means that they can use their team skills.
The easiest way to make team skills available is to put 3 vivosaurs together that are all the same type. There are also some vivosaurs that will tell you who to team them with in their descriptions (Elasmoth, Arsith, Brontoth.... Futabi, F-Raptor, Mihu... Spino, Angato, Sucho... Stygi, Pachy, Goyo). Some, you figure out by experimenting. The ones that I've found (and can remember) are: Nychus, M-Raptor, and Tro... Coatlus, Elasmo, and Venator... I'm sure there were more.
So putting a certain trio on your team will let you use their team skills. You find out by experimenting, or by reading their descriptions. At some point in the game, it mentions putting together by diet or where they're found (on Earth) for a start.