If a tree falls in a forest and no one is around to hear it, does it still make a sound? Not only does the tree make a sound, so do the creatures inhabiting the forest—or in this case—the rainforest deep in the heart of Africa. Using remote sensing cameras and sound recorders, researchers from Florida Atlantic University are the first to capture rare video footage of a newly discovered population of critically endangered monkeys in one of the most remote regions in the world.