Dude, everyone has those questions.
They are clearly not making it up as they go because things in the first episodes are only now being detailed.
The statue, temple and cave with hieroglyphs are apparently an ancient civilization, and perhaps constructed by the Others, who say they have been there a long time and this is their island. The Others clearly age, however, the British accents of the whiz's mom and dad do seem out of character with the rest of the Others, and the genius of the whiz, does lend some question of being a hybrid.
Locke seems to recently tuned-in, and now knows how things are set up, as he has become the leader of the Others.
The whole thing of amazing healing properties, revival from the dead, appearances of dead people who have not been to the island, seemingly ageless Richard, magnetic powers of the island, 'movements' of the island, the Smoke, Jacob, disappearance of Claire, coupled with the statement of 'It's not an island, it's a Place' by Locke, bring me to believe that is is either of divine involvement or extraterrestrial origin, because this **** ain't normal.
There is a theory that all the story stuff is just fluff and the real story is just the Island; that it's all about just 'the Island'.