Chameleon (Chamaeleo)

I. DESCRIPTION:

• The chameleon has zygodactylous toes (fused into opposed bundles of two and three).
  
• It has a long, slender, extensile tongue; independently movable bulged eyes; and a prehensile (grasping) tail. Its body is flattened from side to side.
  
• Chameleons usually grow to between 7 and 10 inches in length.
  

II. DIET:

• Chameleons normally eat insects, though they sometimes dine on birds or invertebrates.
  

III. LIFE CYCLE/SOCIAL STRUCTURE:

• A solitary animal, the slow-moving chameleon is primarily arboreal and strictly diurnal.
  
• The chameleon generally spends the early part of the day warming its body by assuming very dark coloring and by exposing as much surface area as possible to sunlight. After reaching its desired body temperature, it hunts until sundown.
  
• Male chameleons are highly territorial and establish feeding territories, which they defend by exhibiting an elaborate array of posturing, color changing and hissing in attempt to scare off rival males and females not in breeding condition.
  
• As it slowly creeps through tree or shrub branches, the chameleon uses its excellent eyesight to spot insects, using its sticky-tipped tongue to capture unsuspecting prey.
  
• Females lay from two to 40 eggs at a time. They descend from shrubs or trees to bury the eggs in soil or rotting logs; incubation lasts about 3 months.
  

IV. SPECIAL NOTES/ADAPTATIONS:

• The male chameleon responds to other invading males by expanding its body, puffing out its throat and elevating its head flaps. If his attempts are unsuccessful, he will charge the other chameleon and snap his jaw.
  
• Besides serving as camouflage, the chameleon's ability to change colors enables it to communicate with other chameleons.
  
• Chameleons make good tree climbers, thanks to their zygodactyle feet, which grasp like hands.
  
• Its tongue allows the chameleon to snap up insects and grasp hard-to-reach food.
  
• The chameleon's eyes stick out and function independently, allowing it to see forward and backward simultaneously without moving its head.
  
• Chameleons drink water by licking dew and rain droplets off leaves.
  

V. ENVIRONMENTAL IMPACT:

• Chameleons help control insect populations.
  

VI. MORE FACTS ABOUT CHAMELEONS:

• They are characterized by their ability to change body color.
  
• About half the world's chameleon species live on the island of Madagascar — with 59 different species existing nowhere outside of Madagascar.
  
• The chameleon is the only lizard with zygodactyle feet. Although these feet are designed for grabbing branches, on the ground, they are very clumsy, rendering the chameleon an easy target for predators.
  
• The chameleon's tongue can be up to twice the length of its body.
  
• Chameleon is derived from the Greek, meaning "little lion."
  

HOW CAN CHAMELEONS CHANGE THEIR COLOR?
Color range occurs due to mechanism involving dispersion of pigment in cells containing pigment granules that are under the control of the autonomic nervous system. Under the transparent outer skin are two cell layers that contain red and yellow pigments (or chromatophores). Below the chromatophores are cell layers that reflect blue and white light. Even deeper down is a layer of brown melanin. Levels of external light and heat, and internal chemical reactions cause these cells to expand or contract. A chameleon's color change is determined by environmental factors, such as light and temperature as well as by emotions such as fright, victory or defeat in battle with another chameleon, or willingness to mate. It is a misconception that the chameleon changes its color in response to its surroundings.