Will be traveling to Peru, both Amazon River (animals and insects viewed from both water and hiking trails) and mountainous regions (Machu Picchu vistas), and will only be able to take two camera lenses. Need advice. Have Nikon D70 and Nikkor 24-120 VR f/3.5 zoom. Would it be best to buy a Nikkor 70-300 VRII tele zoom or Nikkor 12-24 wide angle zoom to augment the lens I currently own? Or, would a wide angle prime suffice?