Naturally, like other birds, it is assumed that the starling migrated to Bali from other parts of the world, but gradually, over hundreds of years, became unique to Bali.
(the starling; migrated; from other parts of the world) (it; is assumed; ) Context(it is assumed,List([29, 42))):(the starling migrated to Bali from other parts of the world; gradually became; unique to Bali)
it is assumed,List([29, 42))
the starling it the starling migrated to Bali from other parts of the world
migrated is assumed gradually became
from other parts of the world
unique to Bali