It did live on an island Flores in Indonesia, and seaweed and seawater are high in Iodine, but giant rats, dwarf elephants,and Komodo Dragons also lived on the island. They may have eaten all of the seafood before the hobbits got any. Maybe we'll never know. Evolution does have millions of curious threads. I'm sure many people forget that while we have made it so far, Evolution hasn't stopped, and technology may give it some more curious twists which are directly related to us. If two machines get together and produce viable offspring, will that be a new species? Our definition of 'life' is in need of an overhaul. (Perhaps a bit beside the point, but it will be another one of our 'relatives')
I was just reminded of something Mark Twain once said that applies to a point. "It's not change I'm against, it's change for change's sake"
Let's hope we improve.