Let me extend that metaphor further with my personal pet theory: Eorzea is the cradle of all intelligent life in Hydaelyn, the way Africa is the cradle of humanity on Earth.
At the very least, Eorzea would be the "source" of all life in Hydaelyn, being as it is the wellspring of the planet's aether. I like to think of Lake Silvertear as this planet's equivalent of Lake Victoria, one of Earth's largest freshwater lakes.
Which makes me wonder how ecosytems change, in lands so far away from Eorzea. We know that foreigners to Eorzea experience aether sickness when they first arrive to the realm, as their bodies take time to adjust to the higher concentrations of aether in the environment. While the breaking of the seal of Silvertear may well have caused vast amounts of aether to spill over, into lands as far away as Hingashi, it would still be common sense to assume that the levels of aether in these realms would be lower than those of Eorzea.
How does that affect magic, let alone all the fantastical beasts and beast tribes that roam these parts of the world?