Remember the "lost" Amazon tribe that got everyone excited? Well, it turns out that the existence of this "undiscovered tribe" had been known for nearly a century, and that the mission to photograph them from the air was poltically motivated:
Survival International, the organisation that released the pictures along with Funai, conceded yesterday that Funai had known about this nomadic tribe for around two decades. It defended the disturbance of the tribe saying that, since the images had been released, it had forced neighbouring Peru to re-examine its logging policy in the border area where the tribe lives, as a result of the international media attention. Activist and former Funai president Sydney Possuelo agreed that – amid threats to their environment and doubt over the existence of such tribes – it was necessary to publish them.
But the revelation that the existence of the tribe was already established will provoke awkward questions over why a decision was made to try to photograph them – a form of contact in itself – in order to make a political point.
Link - Thanks geekazoid and Moshe!