Make a jungle scene to use as a backdrop (this can perhaps best be done in "layers" - render a section at a time, then composite them in an image editor). Import the backdrop as a Background, and import and pose any trees, rocks, animals, etc. that are an integral part of the scene. There was a long post about this for crowd scenes in the archives; the process should work for a jungle too (since it's, essentially, a "crowd" of plants...).