Most are approximately 15-35 cm in length. They normally display varying shades of green but can turn as dark as black when in great distress. They are sexually dimorphic. Males have three long, pointed horns protruding from the head. These horns are absent or poorly developed in females. The back of the head displays a small crest. There are small spines along the vertebral line. Like other chameleons, Jackson’s chameleon has zygodactylus feet (divided so that two toes point inward and three point outward) which are specialized for tree life, and a prehensile tail which is also used for gripping (Capula, 1989).
The most recognizable feature of all chameleons, however, are their eyes. The pupil is the only part visible from its covering of skin. Each eye rotates a full 180 degrees and is independent of the other. Chameleons have unusually strong control over the curvature of their lenses, and may actually magnify an image. (Land 1995)
Males are territorial and will battle using their horns, which may also be used to attract females. When two males meet, they will turn sideways, flatten their bodies, curl their tails, and thrust their heads forward. They will inflate themselves with air to appear larger and turn brilliant colors. Then they open their mouths to display the varied colors within, while swaying and bobbing with the occasional soft hiss. The submissive male will usually try to hide, will freeze in place, or will try to escape the area. He will fade into drab colors. When males do battle, they will poke each other with their horns and try to push each other off their branches. These fights can cause physical damage to the chameleons
They use stillness and drab natural coloring to protect themselves from predation from birds, snakes, shrews, and lizards.
(Martin, 1990, Zimmermann, 1986).