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. 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.
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.
chameleons have a mating ritual that mimics their threat ritual. The
male will initiate the threat display to the female which includes color
changes, throat inflation and raising the forelegs toward the opponent.
The female then has two choices. She can make threatening gestures
back, in which case she does not want to mate. If she does want to mate,
she will make weak threatening gestures or make no gesture at all in
which case the male recognizes her willingness. The male then will
circle around the female, grab her neck in his mouth and pull himself on
to her back, and insert his hemipenis into her cloacal opening. This
entire process usually lasts about 13 minutes. The female will continue
mating for 11 days but with not with the same male twice in one day.
Gestation lasts approximately 190 days. The young are usually born in
the morning. The female everts her cloaca and the young are delivered
one at a time onto a branch. They are still surrounded by a gelatinous
egg sac and remain asleep until the egg touches the substrate. The young
then awaken and stretch and break through their egg sac. At birth young
are about 5.5 cm long and weigh around 6 gm. After 20 days the females
will copulate again. The young will reach sexual maturity at the age of 9
or 10 months. Average lifespan in captivity, about 8 years.
chameleon's diet consists mainly of insects and spiders. Using their
eyes independently, they will sit completely still and watch for a prey
item to cross their path. When one is spotted, both eyes will converge
and it will sway a bit to better its vision and to confirm the distance
to the meal. Prey is captured by projecting the tongue, which has a
fleshy tip covered with sticky saliva. Prey is then brought back into
the mouth, chewed and swallowed. The tongue, one and a half times the
lizard's length, can reach full length in a sixteenth of a second. They obtain water by lapping drops off leaves. In
the morning, they will sun themselves, curving one side towards the
light and flattening out their bodies and stretching their necks to
increase their surface area. Once warmed, they are able to hunt.
Convention on International Trade in Endangered Species (CITES) lists
all chameleons as threatened. Two reasons for their decline are habitat
destruction and the exotic pet trade. Demand for chameleons encourages
pet suppliers to take them from the wild and ship them great distances;
survival rate may be about 1 in 10, and those that survive arrive
malnourished and stressed. Proper care methods for these lizards is not
well known, so they may be unknowingly mistreated. Captive breeding has
been largely unsuccessful, with the exception of the San Diego Zoo and
some private breeders.