Huh? Dino birds? Where? Transitioning? How? and where is there any evidence of this?
An "Unoccupied niche?" LMAO! What the HECK is that? Evolution works like a roulette table; unorganized premadoral goo rolls round and round, till it falls in an "unoccupied niche". LMAO!
An “unoccupied niche” is like that job I’m going to make for myself, it’s there in theory but no one will be able to see it except in hindsight and then everyone will say how clearly they saw it right from the beginning, it being so obvious and all.
In short it’s unoccupied because it doesn’t exist and it only exists when it becomes occupied. Clear? If yes, I’ll explain again, If no, I’ll stop.
This evolution is great fun!