As they were quickly learning, the greatest challenge they faced from the rain forest came not from any creature or adversary that they could confront and defeat, but from the jungle as a whole—in the ruthless efficiency with which it apportioned food and nutrients, in the bewildering complexity of its defense mechanisms, in the constant demands that it placed upon every one of its inhabitants, and in the ruthlessness with which it dealt with the weak, the hungry, or the infirm.
