Carrying guns and wearing jungle fatigues, the three men don't look like scientists as they push their way through the thick foliage of the Amazon.
They're trying to reach a clearing they've seen on satellite images. When they finally get there, they discover that the largest trees have been uprooted by a tractor. The ground has been seeded with grass to create a pasture for cattle.
Rodrigo Numeriano, 31, finds a piece of a fruit peel, puts it up to his nose and sniffs.
"Someone was just here," he says.
They've found the clues. Now comes the hard part: determining who is causing the damage and who plans to profit.