It's a keyhole.
What a strange symbol.
That symbol represents one of the statues-cum-phonebooths scattered about the island.
I don't see anything except dense jungle.
I don't see anything interesting.
I can see a statue on a cliff overlooking the sea.
It's a statue below a really tall tree.
It's a statue standing in the ruins of an ancient city.
Somebody's looking back at me! Oh, wait, that's just my eye. The lens has turned into a mirror.
It's a small, eye-sized aperture with a crystal in it, like a lens. Maybe some kind of telescope?