During the periods when the sea level was high and flooded most of peninsular Florida, these ancient islands became refuges for plants and animals.
(the sea level; was; high; T:the periods) (the sea level; flooded; most of peninsular Florida; T:the periods) (these ancient islands; became; refuges for plants and animals; T:During the periods)
the sea level the sea level these ancient islands
was flooded became
high T:the periods
most of peninsular Florida T:the periods
refuges for plants and animals T:During the periods