Here's a phylogenetic diagram including some of my headcanons regarding the evolution of the tribes. Also threw in a bunch of my own fan tribes because why not. (Now that I'm looking at it, this could probably be connected to an au)
Some random related notes:
Reefwings, Trenchwings, Shorewings, and Echowings are all subspecies of the Seawing. While Shorewings are the most common and have the largest above-water population, all four can be considered Seawings, and thus would be able to become part of the royal family if they were to marry or bee born into it. Queen Coral herself is actually a cross between Reefwing and Shorewing. All four subspecies can be found all over the ocean, but they are mostly concentrated near the continents.
Darkwings and Starwings are two subspecies of the Nightwing that evolved as a result of the tribe splitting between two locations. Darkwings evolved from the Nightwings located in renewal, and Starwings evolves from the Nightwings located in the rainforest as a result of breeding with Rainwings.
Due to the fact that they share a close common ancestor in the Flamewing, both Skywings and Sandwings have a chance to be born with firescales, due to their fire being naturally hotter than other tribes.
I don't really have anything else to say lol. Have a nice day!