The Earth was Empty

In the beginning, there was nothing. And then the continents and oceans were formed. If you look at this island, you look into the past. Nothing has changed since this island was formed millions years ago. No human hands touched these shoreline. It is still the same as Captain Cook, Nelson and all other famous seafarers saw it. It is the island Ilha da Trindade, in the South Atlantic ocean, some 600 nautical miles offshore the Brazilian coast.
We passed it pretty close this afternoon and saw only a couple of small houses. People are living here, what I understood people from the Brazilian Navy.
But I have no clue what these people are doing here for a living.