I'm putting my answers in spoiler, since this subject, tough interesting, is really out of topic.

Originally Posted by
Penthea
The only reason why I'm not okay with a flying elephant is we haven't seen any wild ones...where are the Ananta getting them from?
Well, according to the tooltip, marids can fly thanks to a "magicked carpets affixed to its back". And those carpets are made by the Ananta, so we probably wouldn't find any wild flying elephants out there.
Still, your point hold for the tyrannosaur as we don't see any wild one in Eureka.

Originally Posted by
Remedi
We don't really know because they haven't gone on a lenghty explanation on how it happens, they have just done a quest about it to explain the change on the pirates of sastasha and that was it we don't know exactly how much aether it takes to create mutations or how long it tales to be able to fly, we don't even know if it's something that can be easily learned, we do know however that a good win aetherconduction can effortlessly make island float though
Interesting, so that's kind of a "grey zone" in the lore, right now?
Still, aren't Sastasha's pirates another story? I thought they were modified by the direct intervention of the primal Leviathan. And on this, it wouldn't be the first time a primal modified someone or something. If memory serves, Odin is doing the same thing with the player that kills him. But mutation by exposition to a large source of aether? That's kind of a first, I think.
And for the islands, you are probably talking about the Churning Mists and the Sea of Clouds. And it's true that they have large amount of crystals that generate a lot of wind aether, preventing them from falling. If I remember well, Bismark was actually feeding on those islands. But the tyrannosaur do not have those kind of crystals in it, so the mystery as to why it can fly still hold for me.
And as Penthea said, we don't see any wild T-rex flying around in Eureka.

Originally Posted by
Berethos
Worth noting:
There seems to be two possibilities - either they have been around for a while and developed the ability, as Eureka - once known as the Isle of Val - was described during those quests as being a fairly dangerous place in the first place, and part of why they chose that region...or what happened to it - the event that registered magicks related to dimensional compression - caused a significant enough shift that creatures on the island were simply warped in ways that changed them without requiring several generations of genetic development.
I need to see the quest text again, but didn't Krile said that those monsters weren't here before the incident of Val happens? (Plus, how can living things survive a dimensional compression...?