"Stay down," whispered Ahlund. "Follow me. And keep quiet."
Justin did not need to be told twice.
They crept along the top of a rocky embankment-one of the only geomorphic elements they had encountered since entering the jungle. Trees jutted out from between the rocks and stretched long, slender trunks upward. Through the veil of their branches, it was impossible to see how far the embankment fell, but Justin was careful to stay several steps away from it at all times. It was still raining, and the ever-present white noise of water crashing through the trees had been the only sound for hours, which made the noises Justin heard now all the more disconcerting.
Some of the noises sounded like guttural grunts, and others, low, whooping whistles accompanied by the swishing and crashing of disturbed undergrowth.