With just four species of dragons of the eighteen that live on the continent of Westeros, the Iron islands possess a variety of niches were these species thrive without being adapted to the same island as the others as all the populations became isolated not by space (as dragons can fly) but by habitat (different resources); also, these dragons are the best example of the adaptive radiation process as a common ancestor species from Westeros established in the different islands and each of the groups adapted to a specific island.
One possible explanation to why this process started on different dragons in the islands is based on Gause’s principle of competitive exclusion as two species that have